Journal articles on the topic 'Nozzles'
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1
Zhang, Shuce, Xueheng Tao, Jinshi Lu, Xuejun Wang, and Zhenhua Zeng. "Structure Optimization and Numerical Simulation of Nozzle for High Pressure Water Jetting." Advances in Materials Science and Engineering 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/732054.
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Three kinds of nozzles normally used in industrial production are numerically simulated, and the structure of nozzle with the best jetting performance out of the three nozzles is optimized. TheR90 nozzle displays the most optimal jetting properties, including the smooth transition of the nozzle’s inner surface. Simulation results of all sample nozzles in this study show that the helix nozzle ultimately displays the best jetting performance. Jetting velocity magnitude alongYandZcoordinates is not symmetrical for the helix nozzle. Compared to simply changing the jetting angle, revolving the jet issued from the helix nozzle creates a grinding wheel on the cleaning surface, which makes not only an impact effect but also a shearing action on the cleaning object. This particular shearing action improves the cleaning process overall and forms a wider, effective cleaning range, thus obtaining a broader jet width.
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Baha, Vadym, Ivan Pavlenko, Kamil Židek, and Olaf Ciszak. "Ensuring the Abrasive Jet Machining Efficiency Using a Nozzle with a Perforated Insert." Machines 12, no. 5 (May 16, 2024): 347. http://dx.doi.org/10.3390/machines12050347.
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Ejector-cleaning devices for abrasive jet machining have various practical applications. The working nozzle is one of the device’s key elements affecting the treated surface quality. There arises the necessity for new approaches to achieving an efficiency increase in abrasive jet equipment nozzles, namely their design improvement and further development of a new, relatively cheap but effective technology for their manufacturing and maintenance. This technology should allow for the high durability of nozzles without being essential for the hardness or wear resistance parameters of the material used for manufacturing. The nozzle should be designed as a long-length perforated insert to allow for radial airflow, forcing the abrasive material (river sand) from the inner walls of the nozzle’s working surface to reduce its friction with the abrasive material. This will result in new wear-out conditions, providing an essential decrease in the wear-out of a nozzle’s working surface. The article aims to develop a more effective design for the working nozzle based on the perforated insert application. The task was set to provide a more detailed experimental and theoretical study of the processes in perforated nozzles to improve their effectiveness. The research resulted in a new design for nozzles with higher efficiency.
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Wang, Guobin, Tongsheng Zhang, Cancan Song, Xiaoqing Yu, Changfeng Shan, Haozheng Gu, and Yubin Lan. "Evaluation of Spray Drift of Plant Protection Drone Nozzles Based on Wind Tunnel Test." Agriculture 13, no. 3 (March 6, 2023): 628. http://dx.doi.org/10.3390/agriculture13030628.
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The use of drones in agriculture is expanding at a brisk pace in crop production due to the superiority in precision, efficiency, and safety of their applicators. However, their potential drift risk also raises concern for users and regulatory authorities. The method of wind tunnel research can effectively evaluate the weighted influence of each drift factor, especially the drift characteristics of the nozzle and spray solution. Based on the wind tunnel test results, centrifugal nozzles have a higher drift risk than hydraulic nozzles, even with a similar DV50. The cumulative drift rate of the centrifugal nozzle at 2 m downwind was 90.1% compared to the LU12001 nozzle’s 40.6% under the wind speed of 3.5 m/s. Compared with the same coding as the flat fan hydraulic nozzle, the IDK nozzle can effectively reduce the drift rate. For the tested nozzles, DV50 and wind speed had a linear relationship with drift rate, and the sampling location had an exponential or logarithmic relationship with drift rate. Spray adjuvants, especially modified vegetable oils, had a significant effect on reducing the amount of drift. The results of this experiment provide a reference for the selection of nozzles and the addition of spray adjuvants. Further clarifying the spray drift characteristics of drones until a drift prediction model is available is still the focus of research.
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Liu, Shi Nian, Wei Su, and Zeng Fu Wei. "Flow Field Simulation of the Nozzle and the Influence of Size." Applied Mechanics and Materials 437 (October 2013): 47–50. http://dx.doi.org/10.4028/www.scientific.net/amm.437.47.
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The nozzle is one of the critical parts in the dry-ice blasting system, spray nozzle's structure and the air supersonic free jet flow field take big influence on cleaning efficiency during the blasting process. Inner flow field of different size nozzles and the flow field of jet flow sprayed by nozzles were simulated with software Fluent, which obtained the distribution results of pressure and velocity of fluid. The result indicated that the supersonic underexpanded jet take place in the nozzle outlet and the shock wave is gained as the pressure at the nozzle exit is greater than the atmospheric pressure. With increasing of the nozzle size, the velocity decrease of airflow become slower, the shock wave transmission distance increase and deduce the stability of the jet flow.
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Wang, Zhi Wu, Kun Zhang, and Long Xi Zheng. "Numerical Simulation of the Nozzle Angles Effect on the Pressure at Thrustwall and Nozzle Outlet of PDE." Applied Mechanics and Materials 705 (December 2014): 92–95. http://dx.doi.org/10.4028/www.scientific.net/amm.705.92.
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In order to investigate the effects of nozzles with different angles on PDE performance, PDE with nozzles of different convergent and divergent angles were simulated and propane-air mixture was used. The simulation results indicated that the effects of nozzles with different angles on the pressure at the thrustwall of PDE and nozzle outlet were not the same. The pressure at the thrustwall and nozzle outlet of PDE with convergent nozzles was higher than that with divergent nozzles, and the pressure peak appeared earlier in the case of convergent nozzles. The peak value of the pressure at the nozzle outlet increased and appeared ahead of time as the convergent angle increased. The peak value of the pressure at the nozzle outlet increased and the evacuation time was prolonged with convergent nozzles. The pressure at the nozzle outlet dropped quickly and the evacuation time was shortened with divergent nozzles.
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Liu, Li Li, and Jian Xin Deng. "Study on Erosion Wear Mechanism of SiC/(W,Ti)C Gradient Ceramic Nozzle Material." Key Engineering Materials 375-376 (March 2008): 440–44. http://dx.doi.org/10.4028/www.scientific.net/kem.375-376.440.
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Idea of functionally gradient material (FGM) theory was used to the design of ceramic nozzle. The purpose was to increase the erosion wear resistance at the entrance of the nozzle in dry sand blasting processes. The SiC/(W,Ti)C gradient ceramic nozzles fabricated by conventional hot pressing. The erosion behavior of the SiC/(W,Ti)C gradient ceramic nozzles were investigated in comparison with the common homologous ceramic nozzles. The experimental results have shown that the ceramic nozzles with a gradient structure have superior erosion wear resistance to that of the common homologous ceramic nozzles under the same test conditions. It was shown that the mechanical properties of the gradient ceramic nozzle materials were greatly improved in comparison with that of the common homologous nozzles. The surface Vickers hardness and indentation fracture toughness of gradient ceramic nozzle were greatly improved compared with that of the common homologous nozzles. Therefore, it is indicated that gradient structures in ceramic nozzles is an effective way to improve the erosion wear resistance of the common homologous nozzles.
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Fu, Lei, Shuai Zhang, and Yao Zheng. "Design and Verification of Minimum Length Nozzles with Specific/Variable Heat Ratio Based on Method of Characteristics." International Journal of Computational Methods 13, no. 06 (November 2, 2016): 1650034. http://dx.doi.org/10.1142/s0219876216500341.
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Two-dimensional (2D) and axisymmetric minimum length nozzles (MLN) with constant and variable specific heat were strictly designed using the method of characteristics. Requirements for the exit Mach number and flow field uniformity were proposed for the nozzles design. In solutions to kernel zone flow field reported previously, violent vibrations of upper wall discrete points at the inlet were observed. Meanwhile, slight compressions could be observed in the flow field of axisymmetric nozzles designed by those methods. In this study, we proposed a novel technique in which the inlet grid is intensified to overcome the limitations mentioned above. Additionally, methods based on conservation of mass and eliminating wave theory were proposed to determine the contour of the nozzle’s upper wall. Inviscid numerical simulations by CFD revealed that the proposed nozzle could meet the requirements for exit Mach number and flow field uniformity in various situations, and axisymmetric nozzles designed from eliminating wave theory exhibited better flow field compared with those designed from conservation of mass.
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Vong, Chin Nee, and Peter Ako Larbi. "Development and Prototype Testing of an Agricultural Nozzle Clog Detection Device." Transactions of the ASABE 64, no. 1 (2021): 49–61. http://dx.doi.org/10.13031/trans.13519.
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HighlightsPrototypes of an agricultural nozzle clog detection system (for 18 nozzles) have been successfully developed.Spray quality characteristics (droplet size, pattern, and coverage) were not significantly affected when testing the device with extended-range nozzles (TeeJet XR8004).Most of the spray quality characteristics were significantly affected when testing the device with ultra low-drift nozzles (John Deere PSULDQ2004).Abstract. Agricultural nozzles are the main components that perform the spraying of agrochemicals, and their proper functionality is a key element for uniform spray application on crops. Because nozzles have small orifices, they can become clogged when there is debris from the agrochemical in the tank. Nozzle clogging during spray application results in poor pest and weed management and increased cost for re-spraying the affected crop row. Measures used to prevent nozzles from clogging include using screens or strainers to filter out debris before it reaches the nozzle tip, as well as performing regular checks on the nozzles. However, nozzle clogging still occurs during spraying despite the precautions taken. Thus, a device that can detect nozzle clogging during spraying is necessary to enable a quicker response that will ensure uniform application across each row of the crop. A novel, patented device for detecting clogged nozzles that is externally attachable to each nozzle on a sprayer boom was developed in the Precision Application Technology Lab at Arkansas State University. The main objective of this article is to present a general description of this prototype nozzle clog detection device and the nozzle clog detection system. Spray droplet size and pattern tests under controlled conditions and spray coverage tests under field conditions were conducted with and without the device to determine if there were significant differences in droplet size, spray pattern, or spray coverage between using and not using the device. The tests demonstrated that this new technology has potential for detecting clogged nozzles without significantly influencing spray quality for extended-range nozzles but not for ultra low-drift nozzles. To increase the reliability of the performance of this new technology, further improvements in the design need to be considered. Keywords: Clogged nozzle, Detection, Droplet size, Prototype device, Spray coverage, Spray pattern.
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PANDA, ANTON, VOLODYMYR MYKOLAJOVYCH ANISIMOV, VOLODYMYR VOLODYMYROVYCH ANISIMOV, IVETA PANDOVA, ANTON KLYMENKO, and PETER ERMAKOV. "CAVITATION NOZZLES WITH EXPANSION CHAMBER." MM Science Journal 2022, no. 4 (November 16, 2022): 6020–25. http://dx.doi.org/10.17973/mmsj.2022_11_2022050.
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An expansion chamber for narrow part of cavitation nozzles is developed. Designs of cavitation nozzles with expansion chamber based on cylindrical nozzle and Venturi nozzle are proposed. The results of calculations of the fluid flow in the presented nozzles show the areas in nozzle, where cavitation is generated, their number, form and power. The plot of volume fraction of vapor phase shows the causes of an increase in the intensity of cavitation in new nozzles with expansion chamber. The main of them is that due to introduction of the expansion chamber, a little area of cavitation generation in the narrow part of cavitation nozzle turns to large one, that causes significant increase in cavitation intensity. The results of comparative experimental studies, which confirm the superiority of cavitation nozzles with the expansion chamber over the basic ones, show that cavitation nozzle with expansion chamber can provide 3 times higher intensity of cavitation, than basic cylindrical nozzle. Also, cavitation nozzle with expansion chamber on the basis of Venturi nozzle can provide 1.5 times higher cavitation intensity, than basic Venturi nozzle.
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Lipnický, Marek, and Zuzana Brodnianská. "The Effect of a New Approach to Cooling the External Heat Exchange Surfaces of a Car Cooler with Air Nozzles on the Cooling Process." Applied Sciences 14, no. 6 (March 7, 2024): 2227. http://dx.doi.org/10.3390/app14062227.
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The paper deals with an experimental investigation of a new approach for cooling the external heat exchange surfaces of a cooler using an air pressure nozzle system. The G12+ coolant (50:50 ethylene glycol/water concentrate) is heated to an operating temperature of 80 °C and cooled by a cooler. Three ways of forced cooling of the external heat exchange surfaces of the cooler are experimentally compared—fan, nozzles, and a combination of nozzles and fan. The spacing between the nozzles and the cooler is variable from 60 to 170 mm in inline and staggered nozzle arrangements. Coolant temperatures in the cooler inlet and outlet pipes are recorded by thermistors. The air pressure nozzle system achieved an improvement in the cooling process compared to a conventional fan. At a spacing of 160 mm, the heat exchange surface is completely covered by the air flow, which leads to a reduction in cooling time and an increase in the temperature difference. The maximum temperature difference of 28.84 °C and 16.90 °C for staggered arrangement of nozzles at a spacing of 160 mm are achieved for the combination of nozzles with fan and nozzles, respectively. When comparing 60 mm and 160 mm spacing, there was an increase in thermal performance of 70.3%, 55.99%, 6.20%, and 1.83% for inline nozzles, staggered nozzles, fan with inline nozzles, and fan with staggered nozzles, respectively. The air nozzle system fully replaces the fan in the cooling process and achieves improved heat dissipation, making the cooling process significantly shorter and more efficient. In addition, the air nozzle system can also be used as an additional equipment for intensification of heat dissipation in combination with the fan.
11
Ma, Lin Wei, Jia Sheng He, An Qing Shu, Xiao Tao Zheng, and Yan Wang. "Structural Integrity Analysis of Nuclear Power Plant Pressure Vessel Penetration Nozzle Repaired." Applied Mechanics and Materials 853 (September 2016): 346–50. http://dx.doi.org/10.4028/www.scientific.net/amm.853.346.
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Primary water stress corrosion cracking (PWSCC) has been observed in CRDM nozzles, BMI nozzles and other penetration nozzles. The industry has used the repair method of replacement of nozzles fabricated of Alloy 690. After the replacement of the nozzle, the structural integrity analysis of new nozzle and welds should be performed to ensure the pressure boundary compliance with the original design requirement. In this paper, the pressurizer top head instrument nozzle of PWR nuclear power plant is evaluated as a typical pressure vessel penetration nozzle. The results showed that the repaired nozzle satisfies the ASME Code design requirement and the crack growth of the postulated flaw in 40 years of the nuclear plant life is acceptable.PWSCC degradation mechanism has been observed in CRDM nozzles, BMI nozzles and other penetration nozzles [1]. In some nuclear power plants built in China earlier, such as DAYABAY nuclear power plant and QINSHAN nuclear power plant, PWSCC degradation mechanism has been found in CRDM nozzle welds which manufactured of Alloy 600 and welded of Alloy 82/182[2]. The repair of the degraded nozzles is the popular choice for the nuclear power plant owners. After the replacement of the nozzle, the structural integrity analysis of new nozzle and welds should be performed to ensure the pressure boundary compliance with the original design requirement. In this paper, the pressurizer top head nozzle of PWR nuclear power plant is evaluated as a typical pressure vessel penetration nozzle. Stress intensities were conservatively determined for pressure and applicable thermal transients and compared to the allowable values of the ASME Code, Section III. Thermal stress of the transients was obtained from 3D finite element model (FEM). Residual stress of J-groove weld was obtained from 2D FEM analysis and used for fracture mechanics analysis. All of the analysis showed that the repaired nozzle satisfies the ASME Code design requirement and the crack growth of the postulated flaw in 40 years of the nuclear plant life is acceptable.
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Etheridge, Robert E., Alvin R. Womac, and Thomas C. Mueller. "Characterization of the Spray Droplet Spectra and Patterns of Four Venturi-Type Drift Reduction Nozzles." Weed Technology 13, no. 4 (December 1999): 765–70. http://dx.doi.org/10.1017/s0890037x00042202.
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Laboratory studies were conducted using a Malvern laser droplet/particle size analyzer to determine the droplet spectra of several venturi-type drift reduction nozzles compared to a standard single, elliptical-orifice flat fan nozzle. Spray solutions of glufosinate, glyphosate, and paraquat were applied through all combinations of five nozzle types (four drift reduction), three tip sizes, and four application pressures. Nozzles were also evaluated for pattern uniformity using water plus surfactant at one pressure. When averaged over herbicide, tip size, and pressure the venturi nozzles collectively produced larger volume median diameter (VMD) droplets than the standard nozzle. The percentage of spray volume in droplets < 205 μm was less for the venturi nozzles (17%) than for the standard nozzle (65%) when averaged across all factors. The order of herbicides producing the largest droplets was paraquat (470 μm) > glyphosate (460 μm) > glufosinate (400 μm), as measured by VMD. The venturi nozzles were more variable in their spray volume distribution than the standard nozzle. Utilization of venturi-type nozzles may minimize the drift potential of the herbicides evaluated but could also lead to uneven herbicide application and subsequent erratic weed control.
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Pan, Xu Dong, Wen Dong Zhu, and Guang Lin Wang. "Servo Valve Nozzle Fuzzy Clustering Analysis Pairing Algorithm." Key Engineering Materials 667 (October 2015): 476–80. http://dx.doi.org/10.4028/www.scientific.net/kem.667.476.
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Electro-hydraulic servo valve is the key component of an electro-hydraulic servo control system, and double nozzle flapper valve is the main type of electro-hydraulic servo valve. Nozzles are the important part of a double nozzle flapper valve, the pairing quality is directly related to the performance of the servo valve .Servo valve is of symmetrical structure, and the use of nozzles is also in pairs. The process of nozzles matched in pairs is called pairing process. Because the orifice diameter of the nozzle is only about 0.2 to 0.3 mm, it is difficult to pair with the method of direct measurements. Besides, as a kind of hydraulic components, nozzles are usually paired by flow rate measured under differential pressure. Two nozzles will be matched to a pair if their pressure-flow rate characteristic curve is within the allowed tolerance. To ensure the success rate of pairing, it usually needs a large number of machined nozzles to be sifted. According to the principle of clustering analysis, we propose a new paring algorithm which can match nozzles efficiently and automatically.
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Ghassemieh, E., H. K. Versteeg, and M. Acar. "The effect of nozzle geometry on the flow characteristics of small water jets." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 220, no. 12 (December 1, 2006): 1739–53. http://dx.doi.org/10.1243/0954406jmes430.
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A wide variety of processes make use of plain orifice nozzles. Fuel injectors for internal combustion engines incorporate these nozzles to generate finely atomized sprays. Processes such as jet cutting, jet cleaning, and hydroentanglement, on the other hand, use similar nozzles, but require coherent jets. The spray or jet characteristics depend on the stability of the flow emerging from the orifice. This problem has been extensively researched for nozzles with diameters above 300 μm. Much less is known about the characteristics of jets produced by nozzles with smaller diameters, where viscous effects and small geometric variations due to manufacturing tolerances are likely to play an increasing role. Results are presented of a wide-ranging investigation of geometry effects on the flow parameters and jet characteristics of nozzles with diameters between 120 and 170 μm. Nozzles with circular cross-section and conical, cone-capillary and capillary axial designs were investigated. For conical and cone-capillary nozzles, the effect of cone angle and effects due to interactions between adjacent nozzles in the multi-hole cone-capillary nozzles were studied. For capillary nozzles, the effects of diameter variations and inlet edge roundness for capillary nozzles were considered. Furthermore, the effect of varying the aspect ratio (ratio of major and minor axes) of elliptical nozzles was studied. Flowrate and jet impact force measurements were carried out to determine the discharge coefficient Cd, velocity coefficient Cv, and contraction coefficient Cc of the nozzles for supply pressures between 3 and 12 MPa. Visualizations of the jet flow were carried out in the vicinity of the nozzle exit in order to identify near-nozzle flow regimes and to study jet coherence. The relationship between nozzle geometry, discharge characteristics, and jet coherence is examined.
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Hsieh, M. F., D. G. Moffat, and J. Mistry. "Nozzles in the knuckle region of a torispherical head: Stress levels and load interaction effects." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 214, no. 1 (February 1, 2000): 31–41. http://dx.doi.org/10.1243/0954408001530191.
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The results of a limited parametric study on the stress levels in knuckle encroaching nozzles in a Klöpperböden torispherical head due to pressure and nozzle loads are presented. The results give support to the CEN TC 54 procedure which requires thickening of the knuckle region for such nozzles for pressure loading. Stress levels due to nozzle loads are shown to be of the same order of magnitude as those in the equivalent axisymmetric nozzle. Studies of interaction diagrams have confirmed the CEN TC 54 proposal for combined loading in axisymmetric nozzles but have shown that a linear interaction rule should be recommended for non-axisymmetric nozzles in heads.
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Hamid, Ahmad Hussein Abdul, Nik Muhammad Hafiz Nik Ismail, Zuraidah Salleh, Mohd Hafiz Mohd Noh, Mohammad Juani Sujana, and Mohamad Amirul Muhammad. "CFD Analysis of Convergent-Divergent Nozzle for Low Altitude Rocket." International Journal of Emerging Technology and Advanced Engineering 12, no. 6 (June 2, 2022): 160–69. http://dx.doi.org/10.46338/ijetae0622_20.
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The convergent-divergent nozzle in rocket engines is used to turn the chemical energy developed via the combustion chamber into kinetic energy. The wall of the nozzle is properly contoured to efficiently accelerate the combustion product towards the nozzle exit. However, for low-to medium-altitude rockets (typically within the range of 10 to 145 km), nozzle contouring increases the overall production cost due to a more complicated fabrication process. The development of the dual conical nozzle seeks to compromise between performance and ease of fabrication. The present investigation seeks to analyze small rocket nozzles involving a typical conical nozzle, Truncated Optimized Contour (TOC) and Truncated Idealized Contour nozzles and newly designed dual conical nozzles. Rocket nozzles with various divergence angles and exit area ratios are numerically analyzed. It was discovered that the best dual conical nozzle can produce an average thrust comparable to that of a standard conical nozzle. In some cases, the dual conical nozzle outperforms its conical and contoured counterparts. Keywords— Dual conical nozzle, TOC nozzle, TIC nozzle, shockwaves, thrust.
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Anilli, Marco, Ali Gökhan Demir, and Barbara Previtali. "Additive manufacturing of laser cutting nozzles by SLM: processing, finishing and functional characterization." Rapid Prototyping Journal 24, no. 3 (April 9, 2018): 562–83. http://dx.doi.org/10.1108/rpj-05-2017-0106.
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Purpose The purpose of this paper is to demonstrate the use of selective laser melting for producing single and double chamber laser cutting nozzles. The main aim is to assess a whole production chain composed of an additive manufacturing (AM) and consecutive finishing processes together. Beyond the metrological and flow-related characterization of the produced nozzles, functional analysis on the use of the produced nozzles are carried out through laser cutting experiments. Design/methodology/approach SLM experiments were carried out to determine the correct compensation factor to achieve a desired nozzle diameter on steel with known processibility by SLM and using standard nozzle geometries for comparative purposes. The produced nozzles are finished through electrochemical machining (ECM) and abrasive flow machining (AFM). The performance of nozzles produced via additive manufacturing (AM) are compared to conventional ones on an industrial laser cutting system through cutting experiments with a 6 kW fibre laser. The produced nozzles are characterized in terms of pressure drop and flow dynamics through Schlieren imaging. Findings The manufacturing chain was regulated to achieve 1 mm diameter nozzles after consecutive post processing. The average surface roughness could be lowered by approximately 80 per cent. The SLM produced single chamber nozzles would perform similarly to conventional nozzles during the laser cutting of 1 mm mild steel with nitrogen. The double chamber nozzles could provide complete cuts with oxygen on 5 mm-thick mild steel only after post-processing. Post-processing operations proved to decrease the pressure drop of the nozzles. Schlieren images showed jet constriction at the nozzle outlet on the as-built nozzles. Originality/value In this work, the use of an additive manufacturing process is assessed together with suitable finishing and functional analysis of the related application to provide a complete production and evaluation chain. The results show how the finishing processes should be allocated in an AM-based production chain in a broader vision. In particular, the results confirm the functionality for designing more complex nozzle geometries for laser cutting, exploiting the flexibility of SLM process.
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Nowruzi, H., and H. Ghassemi. "Effects of Nano-Nozzles Cross-Sectional Geometry on Fluid Flow: Molecular Dynamic Simulation." Journal of Mechanics 34, no. 5 (May 15, 2017): 667–78. http://dx.doi.org/10.1017/jmech.2017.29.
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AbstractNano-nozzles are an essential part of the nano electromechanical systems (NEMS). Cross-sectional geometry of nano-nozzles has a significant role on the fluid flow inside them. So, main purpose of the present study is related to the effects of different symmetrical cross-sections on the fluid flow behavior inside of nano-nozzles. To this accomplishment, five different cross-sectional geometries (equilateral triangle, square, regular hexagon, elliptical and circular) are investigated by using molecular dynamics (MD) simulation. In addition, TIP4P is used for atomistic water model. In order to evaluate the fluid flow behavior, non-dimensional physical parameters such as Fanning friction factor, velocity profile and density number are analyzed. Obtained results are shown that the flow behavior characteristics appreciably depend on the geometry of nano-nozzle's cross-section. Velocity profile and density number for five different cross sections of nano-nozzle at three various measurement gauges are presented and discussed.
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Han, Han, Pengfei Wang, Ronghua Liu, Yongjun Li, Jan Wang, and Yidan Jiang. "Experimental study on atomization characteristics of two common spiral channel pressure nozzles." E3S Web of Conferences 81 (2019): 01022. http://dx.doi.org/10.1051/e3sconf/20198101022.
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Spiral channel pressure nozzles are commonly used pressure nozzles in practical workplaces. In this paper, two kinds of spiral channel type pressure nozzles, namely, spiral hole type and spiral non-porous type, the atomization characteristics and dust reduction efficiency under different spray pressures are discussed and compared. Based on the experimental method, based on the self-designed spray dust-reducing roadway experimental platform, the macro-atomization characteristics of the two nozzles, namely the flow rate, the atomization angle, the range, and the droplet size, were measured. The following conclusions were drawn: (1) The flow rates of both nozzles increase with increasing spray pressure, and the flow coefficient of the spiral non-porous nozzle is small. (2) The change of the atomization angle of the two nozzles first increases and then decreases with the increase of the spray pressure, and the atomization angle of the spiral non-porous nozzle is larger. At the same time, the range of the two nozzles gradually increases as the spray pressure increases, and the range of the spiral perforated nozzle is always larger than that of the spiral non-porous nozzle. (3) When the spray pressure is gradually increased, the droplet size of the two nozzles selected in the experiment is gradually reduced, and the droplet size of the spiral perforated nozzle is always larger than that of the spiral non-porous nozzle before 5 MPa, and then gradually Become smaller. The main reason why the droplet size decreases with the increase of the spray pressure is that the increase of the spray pressure leads to an increase in the spray speed of the water droplets, so that the water droplets are completely split when they are ejected from the nozzle, resulting in a smaller droplet size. In summary, when the spray pressure required in the actual working environment is low, the use of a spiral non-porous nozzle is more conducive to dust reduction.
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KANKKUNEN, ARI, SANTERI KOIVISTO, KARI SAARI, MIKA JARVINEN, JAMES BIGGS, and ANDREW JONES. "Experiments and visualization of sprays from beer can and turbo liquor nozzles." February 2022 21, no. 2 (March 1, 2022): 95–106. http://dx.doi.org/10.32964/tj21.2.95.
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Industrial scale swirl-type black liquor nozzles were studied using water as the test fluid. Simple water spraying experiments were found to be very beneficial for studying and comparing nozzles for black liquor spraying. These kinds of experiments are important for finding better nozzle designs. Three nozzle designs were investigated to understand the functional differences between these nozzles. The pres-sure loss of nozzle 1 (“tangential swirl”) and nozzle 3 (“turbo”) were 97% and 38% higher compared to nozzle 2 (“tan-gential swirl”). Spray opening angles were 75°, 60°, and 35° for nozzles 1, 2, and 3, respectively. Video imaging showed that the nozzles produced sprays that were inclined a few degrees from the nozzle centerline. Spray patter-nation showed all the sprays to be asymmetric, while nozzle 2 was the most symmetric. Laser-Doppler measure-ments showed large differences in spray velocities between nozzles. The spray velocity for nozzle 1 increased from 9 m/s to 15 m/s when the flow rate was increased from 1.5 L/s to 2.5 L/s. The resulting velocity increase for nozzle 2 was from 7 m/s to 11 m/s, and for nozzle 3, it was from 8 m/s to 13 m/s. Tangential flow (swirl) directed the spray 6°–12° away from the vertical plane. Liquid sheet breakup mechanisms and lengths were estimated by analyzing high speed video images. The liquid sheet breakup mechanism for nozzle 1 was estimated to be wave formation, and the sheet length was estimated to be about 10 cm. Sheet breakup mechanisms for nozzle 2 were wave formation and sheet perforation, and the sheet length was about 20 cm. Nozzle 3 was not supposed to form a liquid sheet. Nozzle geometry was found to greatly affect spray characteristics.
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Wei, Zhiming, Heping Zhu, Zhihong Zhang, Ramón Salcedo, and Degang Duan. "Droplet Size Spectrum, Activation Pressure, and Flow Rate Discharged from PWM Flat-Fan Nozzles." Transactions of the ASABE 64, no. 1 (2021): 313–25. http://dx.doi.org/10.13031/trans.14100.
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HighlightsDroplet sizes, activation pressures acting on nozzle orifices, and flow rates were investigated.Droplet sizes varied with duty cycles, nozzle orifice sizes, and PWM solenoid valve manufacturers.Activation pressures decreased as duty cycles decreased and increased as nozzle orifice sizes decreased.Flow rates increased with increases in both duty cycles and nozzle orifice sizes.Abstract. Pulse width modulated (PWM) spray systems can produce variable spray rates for precision applications of pesticide and fertilizer; however, there are also concerns over their spray performance stability. Droplet size distributions, activation pressures acting on nozzle orifices, and flow rates discharged from nozzles were investigated for test combinations of ten PWM duty cycles (10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100%), six flat-fan nozzles with different orifice sizes (XR8001, XR8002, XR8003, XR8004, XR8005, and XR8006), and two PWM solenoid valves from two different manufacturers. Test results showed that the droplet size distribution, activation pressure, and flow rate varied with the duty cycle, nozzle orifice size, and PWM solenoid valve source. For XR8001 and XR8002 nozzles, droplet sizes did not vary significantly with all duty cycles from 10% to 100%. To obtain relatively consistent droplet size distributions, XR8003 and XR8004 nozzles required PWM duty cycles of at least 20%, while XR8005 and XR8006 nozzles required duty cycles of 30% or greater. The activation pressure directly on nozzle orifices increased as the duty cycle increased but decreased as the nozzle orifice size increased. In addition, the same nozzles coupled with PWM solenoid valves from two different manufacturers discharged different flow rates for the same duty cycle in the range of 10% to 90%. Therefore, careful selection of PWM solenoid valves for different orifice nozzles operated at different duty cycles was necessary to achieve consistent variable-rate spray performances. Keywords: Droplet diameter, Variable rate, PWM solenoid valve, Pesticide, Fertilizer, Precision farming.
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Et. al., Santhosh Kumar,. "Computational Analysis Of 2d Aerospike Nozzle With Base Bleed At Different Altitudes." Turkish Journal of Computer and Mathematics Education (TURCOMAT) 12, no. 10 (May 6, 2021): 5878–88. http://dx.doi.org/10.17762/turcomat.v12i10.5406.
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In the present-day scenario, several nozzles are being developed to achieve better efficiency. Among them, the aerospike is one such nozzle. The aerospike nozzles are yet to be utilized in the aerospace sector but are believed to exhibit better performance than the conventional bell-shaped nozzles that are currently in service. The geometry of the aerospike nozzle enables it to adjust to its environment by modifying its outer jet boundary thus, making it more efficient than the other types of nozzles.
Simple approximation method is used to get the coordinates of the nozzle contour using MATLAB. To compare the performance characteristics, both full and truncated spike nozzles were designed using SOLIDWORKS. In order to improve the performance of the truncated aerospike nozzles, they are provided with base bleeds. The flow behaviour was analysed using Computational Fluid Dynamics (CFD) software – ANSYS. These designs were simulated for different pressure outlet conditions, to compare the performance of full length, truncated spike with and without base bleed, at different altitudes.
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Wei, Mingxiao. "Numerical analysis of the effects of the nozzle shape and outlet area of a waterjet propulsion system on its efficiency." Theoretical and Natural Science 11, no. 1 (November 17, 2023): 46–58. http://dx.doi.org/10.54254/2753-8818/11/20230380.
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The waterjet propulsion system is a marine propulsion device prevalently used on contemporary high-speed vessels. The performance of a waterjet propulsion system is considerably affected by the nozzle. In this study, the influences of the shape and the outlet area of a waterjet propulsion system on the efficiency of the propulsion system is investigated using the computational fluid dynamics method. A total of 10 different nozzle designs, including cylindrical and conical nozzles with 5 different outlet areas, are analyzed in terms of nozzle efficiency and overall efficiency, and the possible reasons and explanations behind the variations of the nozzle efficiency and the overall efficiency are proposed in this study. The simulated results indicate that the conical nozzles consistently have higher nozzle efficiency than the cylindrical nozzles, and the maximum nozzle efficiency occurs in the conical nozzle with an outlet area of 60% of the inlet duct area. The abrupt change in the flow direction at the transition between the guide vane section and the nozzle, as well as the skin friction on the nozzle wall, are predominant factors affecting the nozzle efficiency. The waterjet propulsion units equipped with conical nozzles generally have higher overall efficiency than their counterparts equipped with cylindrical nozzles, while the maximum overall efficiency occurs in both the cylindrical nozzle with an outlet area of 50% of the inlet duct area and the conical nozzle with an outlet area of 60% of the inlet duct area. The loss of mechanical energy due to viscosity and turbulence in a propulsion unit is the major source of energy loss, while the kinetic energy carried by the exit flow is also a considerable factor affecting the overall efficiencies of the propulsion units equipped with conical nozzles with relatively large outlet areas.
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Nitish Kumar Gautam, R. J. Patil, Sandeep S. Patil,. "Investigation of Nozzle Shape, Number of Nozzles and Nozzle Inclination Angle and Its Optimization." Tuijin Jishu/Journal of Propulsion Technology 44, no. 4 (October 16, 2023): 1266–79. http://dx.doi.org/10.52783/tjjpt.v44.i4.1008.
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A pressure vessel is a container that holds gases or liquids at a pressure significantly different from the ambient pressure. The nozzles were essential for inlet and outlet of liquid. A pressure vessel analysis is critical for its proper operation. In the present work, aspects have been considered regarding position and orientation of nozzles according to stress and deformation obtained. The whole objective is to use FEA simulation, and determine the best design solution. Two different type of nozzles viz. radial and tangential were incorporated. Different number of nozzles and different inclination angle of nozzle were also incorporated to study the effect of nozzle geometry. However, design of pressure vessels is based on solvent extraction process. It is observed that radial nozzle induced higher stress values as compared to tangential nozzle. However, as inclination angle increases, maximum stress values are increasing for pressure vessel with tangential nozzle as compared to radial nozzle.
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Al-Taie, Arkan, Hussien W. Mashi, and Ali M. Hadi. "THE EFFECT OF CONVERGENT-DIVERGENT NOZZLE PROFILE ON ITS PERFORMANCE." IRAQI JOURNAL FOR MECHANICAL AND MATERIALS ENGINEERING 19, no. 1 (March 8, 2019): 14–43. http://dx.doi.org/10.32852/iqjfmme.v19i1.262.
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The paper presents the effect of convergent-divergent nozzles profile across specified inlet pressures values from (1.5 bar-4 bar), with constant back pressure of (1 bar). The flow of air through three convergent-divergent nozzles was studied theoretically. The flow was assumed to be one-dimensional, adiabatic and reversible (isentropic). The flow parameters like static pressure ratio and Mach number were analyzed. The flow parameters were obtained in term of area ratio along the nozzle. MATLAB code was built in order to find the Mach number along the nozzles, by using Newton-Raphson method. The shockwave position inside the nozzles was determined, using "analytic method". ANSYS fluent 18 was used to simulate the flow through the three nozzles. Two- dimensional, turbulent and viscous models were utilized to solve the governing equations. K-? model was used to model the turbulent effect. The results concluded that, reduction in inlet pressure can not affect the flow upstream the throat. Also the shockwave appearance can be noticed by a sudden rise in static pressure associated with a sharp decrease in Mach number. Shockwave moves toward the throat by reduction the inlet total pressure .By comparison the static pressure distribution along the three nozzles where can be deduced that the profile has an effect on the flow character i.e. (static pressure Mach no).The best performance among the nozzles is the performance of nozzle (N1), which (75%) of its length work as nozzle at the lowest inlet pressure of (1.5bar) while (44% and 60%) of the nozzles length for (N2 and N3) respectively work as the nozzle.
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Wang, Zixin, Yue Jiang, Jialing Liu, Hong Li, and Hao Li. "Experimental Study on Water Distribution and Droplet Kinetic Energy Intensity from Non-Circular Nozzles with Different Aspect Ratios." Agriculture 12, no. 12 (December 12, 2022): 2133. http://dx.doi.org/10.3390/agriculture12122133.
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(1) Background: In sprinkler irrigation systems, the water distribution and droplet kinetic energy are affected by the shape of the nozzle. In this paper, the effects of working pressure and aspect ratio (L/D) of circular and non-circular nozzles (diamond and ellipse) on water distribution and droplet kinetic energy intensity were investigated; (2) Methods: The hydraulic performance of a PY15 impact sprinkler with circular and non-circular nozzles was assessed under different working pressures, and the droplet diameter, velocity, and kinetic energy intensity were measured by a 2D video disdrometer. Moreover, the coefficient of variation (CV) and form factor (β) were introduced to represent the water distribution and droplet characteristics; (3) Results: The results revealed that, under the same working pressure, the CV of the diamond nozzle was the smallest compared with that of the circular and elliptical nozzles, reflecting a more uniform water distribution. The uniformity of water distribution was the best when the L/D of the elliptical nozzle was the smallest. In general, the larger the outlet diameter, the larger the wetted radius and water application rate. In addition, the smaller the L/D, the smaller the peak water distribution value and the radial increase of the kinetic energy intensity of a single nozzle. The maximum droplet kinetic energy per unit volume of the elliptical nozzle was the smallest compared with that of the circular and diamond nozzles. The circular nozzle at 200 kPa and the diamond and elliptical nozzles at 100 kPa obtained the highest uniformity coefficients of combined kinetic energy intensity distribution, which were 55.93% (circular), 67.59% (diamond), and 57.78% (elliptical) when the combination spacings were 1.0 R, 1.1 R and 1.2 R, and 1.0 R, respectively. Finally, the fitting function of unit volume droplet kinetic energy, distance from the nozzle, L/D, and working pressure of non-circular nozzles was established, and a fitting coefficient of 0.92 was obtained, indicating that the fitting equation was accurate; (4) Conclusions: At low working pressures, the elliptic and diamond nozzles showed better water distributions than the circular nozzle. The distal average droplet diameters of the sprinkler with non-circular nozzles were found to be smaller than those produced by the circular nozzle.
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Aryadi, Ari, Reza Febriano Armas, and Budi Utomo Wisesa. "Design and Development of a Special Service Tools Sliding Hammer for Removing Injector Nozzles on the SAA4D125E Diesel Engine." MOTIVECTION : Journal of Mechanical, Electrical and Industrial Engineering 5, no. 3 (September 30, 2023): 513–22. http://dx.doi.org/10.46574/motivection.v5i3.265.
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This research focuses on designing a specialized tool called Special Service Tools Nozzle Attachment with a Sliding Hammer to remove injector nozzles in diesel engines. The fact that the long cycle time in the manual removal process of injector nozzles can be streamlined through this tool is emphasized. The researcher designed and developed this tool with the assistance of CAD. The research results show that by using this tool, the cycle time for removing injector nozzles can be reduced from 23 minutes to just 13 minutes. This indicates a significant improvement in work efficiency and productivity. This research has important implications for the industry, especially in the maintenance and repair of diesel engines.
Penelitian ini berfokus untuk merancang-bangun sebuah alat khusus yang disebut Special Service Tools Nozzel Attachment dengan Sliding Hammer untuk melepas injector nozzle pada mesin diesel. Fakta bahwa cycle time yang lama dalam pengerjaan proses pelepasan injector nozzle yang dilakukan secara manual diharapkan dapat di efisiensikan melalui alat ini. Peneliti merancang dan mengembangkan alat ini dengan bantuan CAD. Hasil penelitian menunjukkan bahwa dengan menggunakan alat ini, cycle time untuk melepas injector nozzle dapat ditekan dari 23 menit menjadi hanya 13 menit. Hal ini menunjukkan peningkatan yang signifikan dalam efisiensi waktu pengerjaan dan produktivitas hal ini memiliki implikasi penting dalam industri, terutama dalam perawatan dan perbaikan mesin diesel.
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Heuer, Miriam, Mehdi Stiti, Volker Eras, Julia Scholz, Norus Ahmed, Edouard Berrocal, and Jan C. Brune. "High-Speed Fluorescence Imaging Corroborates Biological Data on the Influence of Different Nozzle Types on Cell Spray Viability and Formation." Journal of Functional Biomaterials 15, no. 5 (May 14, 2024): 126. http://dx.doi.org/10.3390/jfb15050126.
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Treating severe dermal disruptions often presents significant challenges. Recent advancements have explored biological cell sprays as a promising treatment, but their success hinges on efficient cell delivery and complete wound coverage. This requires a good spray distribution with a small droplet size, high particle number, and ample surface coverage. The type of nozzle used with the spray device can impact these parameters. To evaluate the influence of different nozzles on spray characteristics, we compared air-assisted and unassisted nozzles. The unassisted nozzle displayed small particle size, high particle number, good overall coverage, high cell viability, preserved cell metabolic activity, and low cytotoxicity. Air-assisted nozzles did not perform well regarding cell viability and metabolic activity. Flow visualization analysis comparing two different unassisted nozzles using high-speed imaging (100 kHz frame rate) revealed a tulip-shaped spray pattern, indicating optimal spray distribution. High-speed imaging showed differences between the unassisted nozzles. One unassisted nozzle displayed a bi-modal distribution of the droplet diameter while the other unassisted nozzle displayed a mono-modal distribution. These findings demonstrate the critical role of nozzle selection in successful cell delivery. A high-quality, certified nozzle manufactured for human application omits the need for an air-assisted nozzle and provides a simple system to use with similar or better performance characteristics than those of an air-assisted system.
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Semykin, S. І., Т. S. Golub, and V. V. Vakulchuk. "Research on the physical model of features of the behavior of a two-phase bath at top blowing through a tip with folded nozzles." Fundamental and applied problems of ferrous metallurgy, no. 34 (2020): 129–38. http://dx.doi.org/10.52150/2522-9117-2020-34-129-138.
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At the previous stage of research using a physical model of an oxygen converter, the results of studying the features of purging a single-phase liquid through a single composite nozzle were obtained. The aim of this work was to study the behavior of a two-phase bath using a multi-nozzle lance with folded nozzles. At this stage of the study, silicone oil was used to simulate the slag phase of a two-phase bath. The peculiarities of the influence of experimental nozzles on the processes of mixing and foaming of two phases were studied. Three variants of the experimental nozzle design were investigated: a combination of a conventional and a slit nozzle with a ratio of their areas of 1: 1, 1: 2 and 2: 1. It is established that the use of a tip with four nozzles during purging from above promotes the active formation of a two-layer foamed emulsion on the surface of the bath. Comparison of the operation of the tip with folded nozzles with a tip with a cylindrical indicates more active mixing of the two liquids and the formation of a more stable and much higher layer of foamed emulsion. The most favorable conditions for the organization of full mixing of the two phases in the converter bath are formed when using folded nozzles with a slit size of about 35% and a ratio of slot and nozzle area of 1: 2. To intensify the mixing processes in the upper zone of the unit, it is most expedient to use folded nozzles with a larger fraction of the slit (up to 65%) and the ratio of the areas of the components of the nozzle 2: 1. The use of nozzles with equal areas of components in the studied conditions does not have a positive effect on metabolic processes in the converter bath.
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Haga, Toshio, Kenta Takahashi, Shinji Kumai, and Hisaki Warari. "Casting of a Wire Inserted Strip Using a Twin Roll Caster Equipped with Two Nozzles." Advanced Materials Research 337 (September 2011): 556–59. http://dx.doi.org/10.4028/www.scientific.net/amr.337.556.
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Casting of a wire inserted strip was investigated using a downward melt drag twin roll caster. A nozzle was mounted to each roll. The wire was inserted between the lower and upper strip. Effect of use of two nozzles on the insertion of the wire was investigated. The insertion of the wire by the two nozzles was easier than one nozzle. The surfaces of the wire inserted strip cast using two nozzles was more sound than that cast using one nozzle. The position of the wire at thickness direction was almost center. When different aluminum alloys were poured from an upper nozzle and from a lower nozzle, a wire inserted clad strip could be cast.
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Sasaki, Takumi, Yoshiaki Miyazato, Junji Inamoto, Takahiro Yamamoto, and Atsushi Nakamura. "Development of Firefighting Equipment for Efficient Firefighting Strategy (Development of New Nozzle)." Journal of Disaster Research 10, no. 4 (August 1, 2015): 620–26. http://dx.doi.org/10.20965/jdr.2015.p0620.
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We have developed a new type of hose nozzle, which uses either water or compressed air foam (CAF), as a more efficient fire-fighting strategy. In this paper, a description of the measured spray range and foam expansion of both the prototype nozzle and conventional nozzles is given. The results show that the spray range of the prototype nozzle is equal or superior to that of conventional nozzles. The foam expansion capability of the prototype nozzle is far superior to that of existing nozzles. From these results, it was confirmed that the new type of hose nozzle suggested in this paper will be an effective addition to existing firefighting equipment, resulting in a more efficient firefighting strategy.
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Zandstra, Bernard H., and Thomas F. Wallace. "Postemergence Weed Control in Onions (Allium cepa) with Air-assisted, Flat Fan, and Rotary Nozzles." Weed Technology 3, no. 3 (September 1989): 467–71. http://dx.doi.org/10.1017/s0890037x00032589.
Full textAbstract:
Field studies were conducted in 1984, 1985, and 1986 to compare standard flat fan nozzles, low-volume flat fan nozzles, rotary controlled droplet applicators, and air-assisted nozzles for postemergence weed control in onions with oxyfluorfen and fluazifop-P. Herbicides applied with flat fan nozzles at 47 or 190 L/ha controlled broadleaf and grass weeds as good or better than with the other nozzles. Oxyfluorfen applied with flat fan nozzles controlled common lambsquarters and ladysthumb best. None of the nozzles improved control of the difficult marsh yellowcress. Carrier volume had minimal effect on weed control. Nozzle and carrier volume did not affect onion yield.
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Acar, M., R. K. Turton, and G. R. Wray. "Air Flow in Yarn Texturing Nozzles." Journal of Engineering for Industry 109, no. 3 (August 1, 1987): 197–202. http://dx.doi.org/10.1115/1.3187118.
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The air-jet texturing process, a purely mechanical means of texturing continuous filament yarns, is described. Industrial texturing nozzles are reviewed and categorized in two groups, either as converging-diverging or cylindrical type nozzles. A mathematical model is developed for the complex airflow in cylindrical type texturing nozzles, and experimental data obtained from various nozzles verify the flow predicted by this model. The mathematical model is also shown to be in good agreement with the data obtained from a modified experimental nozzle, which has a trumpet shaped diverging exit. Further experimental work with a scaled-up model of a typical industrial texturing nozzle is also reported.
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Gai, Guodong, Abdellah Hadjadj, Sergey Kudriakov, Stephane Mimouni, and Olivier Thomine. "Numerical Study of Spray-Induced Turbulence Using Industrial Fire-Mitigation Nozzles." Energies 14, no. 4 (February 20, 2021): 1135. http://dx.doi.org/10.3390/en14041135.
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A numerical investigation of the spray-induced turbulence generated from industrial spray nozzles is carried out to better understand the roles of the nozzle spray on the fires or explosions in different accidental scenarios. Numerical simulations are first validated against experimental data in the single nozzle case using the monodisperse and polydisperse assumption for droplet diameters. The polydispersion of the nozzle spray is proven to be necessary to correctly predict the gas and droplet velocities. The turbulent kinetic energy has dominant values inside the spray cone, decreases rapidly with the vertical distance from the spray nozzle, and is strongly affected by the spray droplet diameter. On the contrary, the integral length scale is found to have high values outside the spray cone. Two interacting sprays injected from different nozzles are then investigated numerically using the validated polydisperse model. The water sprays generated from such industrial nozzles can generate turbulence of high intensity in the near-nozzle region, and this intensity decreases with the distance from the nozzles. A better understanding of the turbulence generated by the spray system can be beneficial for the evaluation of several important phenomena such as explosion enhancement. The guideline values obtained from this investigation of single and double nozzles can be useful for large-scale numerical simulations.
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Hamaidia, Walid, Toufik Zebbiche, Mohamed Sellam, and Abderrazak Allali. "Performance improvement of supersonic nozzles design using a high-temperature model." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 233, no. 13 (February 27, 2019): 4895–910. http://dx.doi.org/10.1177/0954410019831862.
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The aim of this paper is to discuss the development of new contours of axisymmetric supersonic nozzles giving a uniform and parallel flow at the exit section, to improve the aerodynamic performances compared to the minimum length nozzle, by increasing the exit Mach number and the thrust coefficient, and by reduction of the nozzle's mass, while holding the same throat section between the two nozzles. The new nozzle is named the best performance nozzle. Its form contains a cylindrical central body and an external wall for the flow redress. The study is done at high temperature, lower than the dissociation threshold of the molecules. The variation of the specific heats with the temperature is considered. The design is made by the method of characteristics. The predictor-corrector algorithm is used to make the numerical resolution of the obtained nonlinear algebraic equations. The validation of results is made by the convergence of the numerical critical sections ratio with that given by the theory. The comparison of the results is made with the minimum length nozzle since it is currently used in the aerospace propulsion. The design depends on M E, T0, y body, y*, and the mesh generation. The application is done with air. A computational fluid dynamics verification for the under nozzle expressed regime has shown that a flow separation with the wall is observed because of the side-loads, which are reduced for this new nozzle compared to the minimum length nozzle.
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Meng, Jin Long, and Zhao Qin Yin. "Numerical Simulation on the Parallel Combined Nozzles of Mini/Micro Gas Flow Standard Device." Advanced Materials Research 472-475 (February 2012): 2000–2003. http://dx.doi.org/10.4028/www.scientific.net/amr.472-475.2000.
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The flow characteristics in mini/micro sonic nozzles have been studied in this paper using the computational fluid dynamics (CFD) method. The result shows that the flow rate of the parallel combined nozzles is not equal to but smaller than that of the sum of the nozzles. The reason is the each effect of the air after nozzles, which changes the flow field parameters .The more number of the parallel combined nozzles, the bigger error exits between actual flow rate and that of the sum of the nozzles. The result is consistent to the experiment. The study also shows the smaller of the nozzle’s diameter, the bigger error exits.
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Chen, Xiong, Ming Qiu, Jie Song, Longxu Ma, and Zhenqiang Liao. "Dual Nozzle Weapon Power Couple Vibration Controller With Delayed Rear Nozzle." Journal of Physics: Conference Series 2125, no. 1 (November 1, 2021): 012034. http://dx.doi.org/10.1088/1742-6596/2125/1/012034.
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Abstract Aiming at the problem that the firing accuracy of barrel weapon is affected by the violent vibration during continuous firing, a double-nozzle vibration controller using the energy of gunpowder gas in the chamber is proposed. The synchronous external injection of the double nozzles of the controller is realized by the delayed ejection of the rear nozzles, so as to generate a power couple to balance the recoil flipping torque of the barrel weapon to achieve the stable firing effect of reducing the bore vibration. A double-nozzle vibration controller with a delayed rear nozzle for a chain gun is designed. The rigid-flexible coupling dynamic model of a chain gun with a double-nozzles vibration controller was established considering the two-phase flow of propellant gas in the barrel and airway. The numerical simulation of the muzzle vibration characteristics of the original weapon and a chain gun equipped with a double-nozzles vibration controller is carried out respectively, and the effectiveness of the double-nozzles dynamic couple vibration controller for the continuous firing vibration control of the barrel weapon is verified.
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Elangovan, S., and E. Rathakrishnan. "Studies on high speed jets from nozzles with internal grooves." Aeronautical Journal 108, no. 1079 (January 2004): 43–50. http://dx.doi.org/10.1017/s000192400000498x.
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Experiments were carried out on jets issuing from circular nozzles with grooved exits and the results compared with those of the plain nozzle. The plain nozzle had an exit diameter of 10mm. Because of the introduction of semi-circular grooves at the exit, the effective or equivalent diameter of the grooved nozzles was 10·44mm. The groove lengths were varied as 3, 5 and 8mm. The nozzles were operated at fully expanded sonic and underexpanded exit conditions. The corresponding fully expanded Mach numbers were 1·0 and 1·41. The shock cell structure of the underexpanded jets from grooved nozzles appeared to be weaker than that of the plain nozzle, as indicated by lesser amplitudes of the cyclic variation of the Pitot pressure. The iso-Mach contours indicate that the jet spread along the grooved plane is significantly higher than that along the ungrooved plane. Off-centre peaks were observed in the mean pressure profile of underexpanded jets from grooved nozzles. They were probably due to the streamwise vortices shed from the grooves.
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Liu, Ding Ping, and Bing Jie Zhang. "Influence of Different Outlet Diameters on Atomization Performance of Liquid Beset Gas Nozzles." Advanced Materials Research 550-553 (July 2012): 3184–87. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.3184.
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The wet FGD system with the characteristics of stable and mature, which had been widely used in the large thermal power plants. In this system, spray nozzle plays a key role, and the atomization performance of the spray nozzle affects the desulfurization reaction rate and efficiency directly. A new type spray nozzle, liquid beset gas nozzle was came up with in this article. It makes use of compressed gas in the internal pipeline to crush the liquid flowed out of the external pipeline into small particles. To optimize the nozzle's structure and develop its atomization performance, then considered outlet diameters of nozzle as one of the main influencing factors, sets three outlet diameters of nozzles: 4mm, 5mm and 6mm. This experiment with water for medium uses a laser particle size analyzer and a high speed camera for analysis to take atomization performance's tests of liquid beset gas nozzles under different outlet diameters and working conditions. The results of experimental studies were concluded. Firstly, when the outlet diameter is 5mm, the total spraying performance was the best. Because this outlet diameter can make the nozzle be in a balance between effective crush, fully mixing and jams preventing. Secondly, the new type nozzle had certain adaptability, when working pressures changed, and can be widely used in the wet FGD system.
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Yasir, La Ode, Ridway Balaka, and Nanang Endriatno. "Analisa Pengaruh Variasi Jumlah Nozzle Dengan Memanfaatkan Ketinggian Aliran Air Terhadap Daya Listrik Yang Dihasilkan Turbin Pelton." Enthalpy : Jurnal Ilmiah Mahasiswa Teknik Mesin 7, no. 3 (August 22, 2022): 100. http://dx.doi.org/10.55679/enthalpy.v7i3.26504.
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The performance of a Pelton turbine is influenced by the height, flow velocity, blade angle, number of nozzles, flow size and number of blades and nozzle spray distance. The purpose of this study was to determine the effect of variations in the number of nozzles and nozzle angles on the power produced by the PRLton turbine. The test results show that the more nozzles used, the greater the power generated and the smaller the nozzle angle, the greater the power generated. In position I using 1 nozzle, at an angle of 25o the electrical power produced is 6.16 Watt, at an angle of 30o the electric power produced is 2.65 Watt, at an angle of 45o the electrical power generated is 0.1 Watt. While in position II using 2 nozzles, , at an angle of 25o the electrical power produced is 7.56 Watts, at an angle of 30o the electrical power generated is 3.76 Watts, at an angle of 45o the electrical power generated is 0.24 Watts.Keywords: Electric power, Nozzle, Pelton turbine
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Deng, Jian Xin, Yang Yang Chen, and You Qiang Xing. "Erosion Wear Resistance of CWS Laminated Ceramic Nozzles." Advanced Materials Research 538-541 (June 2012): 1915–19. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.1915.
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In coal-water-slurry (CWS) boilers, the nozzle is eroded continuously by the abrasive action of the CWS, and there are high temperature and temperature gradient inside nozzle, which may cause large tensile stress and lead to an increased erosion wear of the nozzle. In this paper, Al2O3/(W,Ti)C+Al2O3/TiC laminated ceramics were developed to be used as nozzles in CWS boilers. The purpose is to reduce the tensile stresses at the nozzle during the CWS burning process. The value of the residual stresses, which arise from a mismatch between the coefficients of thermal expansion of the constituent phases and neighbouring layers, was calculated by means of the finite element method. The erosion wear behavior of the laminated nozzles was investigated and compared with an unstressed reference nozzle. Results showed that the laminated ceramic nozzles exhibited an apparent increase in erosion wear resistance over the unstressed reference one. It is suggested that laminated structures in ceramic nozzles is an effective way to improve their erosion wear resistance in industrial CWS boilers.
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Larocca de Souza, Larissa, and Marcelo L. Moretti. "Carrier Volume and Nozzle Effect on 2,4-D and Glufosinate Performances in Hazelnut Sucker Control." HortScience 55, no. 11 (November 2020): 1848–52. http://dx.doi.org/10.21273/hortsci15317-20.
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Hazelnut (Corylus avellana L.) basal sprouts, or suckers, are removed to train trees as a single trunk, facilitating mechanization. Suckers are routinely controlled with herbicides, often by using nozzles that generate fine droplets and spray volumes as high as 934 L·ha−1, making spray drift a concern. Spray nozzle type and carrier volume can impact herbicide efficacy and drift. Field studies compared the efficacy of 2,4-D and glufosinate in controlling suckers when applied with a flat-fan nozzle, producing fine droplets, to a TeeJet air-induction nozzle, producing ultra-coarse droplets. These nozzles were evaluated at 187 and 374 L·ha−1. Nozzle and carrier volume did not affect the efficacy of 2,4-D based on control, sucker height, or dry weight. The efficacy of glufosinate was unaffected by nozzle type or spray volume in most evaluations. These results indicate that hazelnut suckers can be effectively controlled using drift-reduction nozzles with lower carrier volumes (187 L·ha−1). Drift-reduction nozzles, coupled with lower spray volume, can maintain herbicide efficacy, minimize drift risk, and reduce cost.
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Orel, Vadym, Oksana Matsiyevska, Bohdan Pitsyshyn, and Maksym Tseniukh. "Influence of throttling and nozzles switching sequence on indicator of water distribution uniformity in cooling tower model." Energy engineering and control systems 9, no. 1 (2023): 54–59. http://dx.doi.org/10.23939/jeecs2023.01.054.
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The article analyzes factors leading to non-uniformity of water distribution in cooling towers. These include imperfections in the design of pipelines and nozzles of the water distribution system of cooling towers. Previous studies conducted on a model of the water distribution system of the tower-type cooling system at Rivne Nuclear Power Plant have revealed uneven water distribution on the nozzles. Simulation of the simultaneity of nozzle activation showed that the nozzle that is activated first has the highest flow rate. Therefore, to achieve acceptable uniformity of water distribution, this nozzle was throttled using a throttling orifice plate. It has been shown that such throttling is effective even in the presence of hydrodynamic cavitation at orifice plate diameter ratios of 0.449...0.624. When four model nozzles are activated one after the other, the flow rate of the first nozzle decreases both with and without throttling. At the same time, increase in the number of working nozzles up to four does not significantly affect the flow rate of the first nozzle.
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Rohinish Khurana, Shashi Kumar Singh, and Anoop Dixit. "Nozzle Spacing on Sprayer Boom." Journal of Agricultural Engineering (India) 44, no. 3 (September 30, 2007): 87–91. http://dx.doi.org/10.52151/jae2007443.1290.
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Agricultural sprayers are frequently used to spray pesticides on standing crops to avoid pest attack. Nozzles are placed on sprayer boom in such a way that the chemical is spread evenly over the plant canopy. The spacing between the nozzles on the boom of commonly used sprayers is quite speculative and not based on the type of nozzle, the discharge from the nozzle, operating pressure, height of the boom, etc. A computer program was developed to select appropriate spacing between the nozzles based on operating pressure, height, spray pattern, etc. The best-suited nozzle spacing was calculated on the basis of overlap of the spread patterns., Coefficient of Variation was calculated for the different levels of overlap of the spread patterns. Spacing for which the Coefficient of Variation was minimum was taken as the best suitable spacing for nozzles on the sprayer boom. The program was validated by using operational parameters of a Triple Action Nozzle with a hollow cone spread pattern. The nozzle was operated at working pressure of 4.0 kglcm2, at a height of 40 cm moving at the forward speed of2.5 km/h. The best spacing was found to be around 57 cm. The program was also used to find out the number of nozzles required for a given boom length and the total volume of chemical sprayed per hectare.
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Dong, Pengbo, Keiya Nishida, and Youichi Ogata. "Characterization of multi-hole nozzle sprays and internal flow for different nozzle hole lengths in direct-injection diesel engines." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 231, no. 4 (August 5, 2016): 500–515. http://dx.doi.org/10.1177/0954407016653890.
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Multi-hole nozzles have a wide range of application in the fuel supply system of modern diesel engines, although single-hole nozzles dominate basic internal flow and spray research. The parameters of the nozzle geometry are crucial factors that can alter the internal flow dynamics of the nozzle and the consequent spray behaviours. The novelty of this study lies in implementing the application of practical prototype mini-sac multi-hole diesel nozzles to experimental and numerical studies. The internal flow and spray characteristics generated by practical multi-hole (10-hole) nozzles with different sac wall thicknesses (0.4 mm, 0.6 mm and 0.8 mm) were investigated in conjunction with a series of experimental and computational methods using a constant injection quantity (2 mm3/hole). Globally, the analysis mainly concentrated on different nozzle flow dynamics, different injection processes and different spray morphologies. Specifically, the high-speed video observation method was applied to visualize the injection processes and the spray evolution of different nozzles inside a high-pressure vessel. Furthermore, numerical simulations were conducted to reveal the three-dimensional nature of the internal flow inside different configurations; this was instructive in helping us to understand better the mechanism behind the spray behaviours. The results indicate that intense cavitating, turbulent and spiral rotating flow patterns occur inside practical multi-hole nozzles, and the consequent sprays emerging from the nozzles are perturbed, asymmetrical and unstable in both the near field and the far field. Moreover, a decrease in the nozzle hole length can increase the effects of cavitation, turbulence, the void fraction and the axial and radial injection velocity components on the nozzle hole exit; this is accompanied by an intriguing longer injection duration, wider near-field and far-field spray widths, a lower injection rate, and overlapping or even shorter spray propagation. However, these changes are not linear, and different parameters have different sensitivities to the variation in the nozzle hole length.
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Gonzalez-Trejo, Jesus, J. Raul Miranda-Tello, Francisco Cervantes-de-la-Torre, Ignacio Carvajal-Mariscal, Florencio Sanchez-Silva, Ruslan Gabbasov, and Cesar A. Real-Ramirez. "Experimental Analysis of a Slab Continuous-Casting SEN with an Inner Flow Divider." Metals 12, no. 7 (June 27, 2022): 1097. http://dx.doi.org/10.3390/met12071097.
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In slab continuous-casting machines, the quality of the finished product mainly depends on the hydrodynamic behavior of the molten steel in the cavity of the continuous-casting mold, where the submerged entry nozzle is the central element. Recently, a nontraditional nozzle design was reported, where a solid barrier attached to the inner bottom wall of the nozzle divides its internal volume, particularly around the outlet ports. The solid barrier was named a flow divider. In this work, the effect of the flow divider is analyzed by comparing the performance of traditional nozzles with the performance of nozzles altered with the flow divider. The performance of the nozzles was evaluated experimentally, employing a scaled model of the mold section, using cold water as the working fluid. The shape of the nozzle outlet jets and the fluid flow pattern in the mold cavity were used to determine the performance of the nozzles. In addition, several factors affecting the process stability and the quality of the product were analyzed: the casting speed, the tilt of the nozzle outlet ports, and the injection of gas in the liquid stream entering the nozzle. The analysis showed that for the nozzles with the flow divider, (i) the outlet jets are narrow and symmetric, (ii) the symmetrical double-roll flow pattern in the mold cavity is obtained, (iii) the liquid-free surface is stable and has low distortions, and (iv) the flow divider neither increases the bubble breakage nor the coalescence between them.
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Subr, Alaa Kamel, Józef Sawa, and Stanisław Parafiniuk. "The Change in Spectrum of Drops in the Exploitation Process of Agricultural Nozzles." Agricultural Engineering 20, no. 2 (July 1, 2016): 101–8. http://dx.doi.org/10.1515/agriceng-2016-0031.
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AbstractAgricultural nozzles usually produce a different drops size depending on the pressure and the physical condition (work life) of the nozzle besides producing a wide range of the drops spectrum in the spray cloud. In this paper the standard flat fan nozzles were investigated regarding the effect of the working pressure and the nozzle physical condition (new and worn nozzles). The size of drops and the spectrum of drops across the long axis of the spray pattern were examined by using Sympatec GmbH Laser Diffraction. Reducing the working pressure from 3 to 2 and then to 1 caused production of larger drops, also using worn nozzles (especially with lower pressure) changed the drops size which is expected to be produced from the new nozzles. The standard flat fan nozzles produced a wide range of the drops spectrum inside the spray cloud, generally small drops (less than 150 µm) concentrated in the middle of the spray pattern while the big drops (250-350µm) were situated on the edge positions (70 cm from the centerline) of the spray pattern.
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Yoga Pratama, I. G., I. W. Arta Wijaya, and I. N. Budiastra. "ANALISIS PENGARUH PENGGUNAAN DUA NOZZLE TERHADAP DAYA OUTPUT LISTRIK PADA PROTOTYPE PEMBANGKIT LISTRIK TENAGA PIKOHIDRO DENGAN MENGGUNAKAN TURBIN TURGO." Jurnal SPEKTRUM 10, no. 4 (December 31, 2023): 85. http://dx.doi.org/10.24843/spektrum.2023.v10.i04.p11.
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This study uses two nozzles on the PLTPH prototype with a turgo turbine because this research wants to apply the use of two nozzles in a pelton turbine. This study aims to determine the effect of using two nozzles on the output power produced by the PLTPH prototype with the direct test method on the prototype made. This two-nozzle PLTPH prototype with a turgo turbine can produce higher turbine rotation than the existing conditions. The final result is the highest rotation on the turbine using 2 nozzles where the A nozzle angle is 70° based on the x axis and the B nozzle angle is 60° based on the y axis of 752.2 rpm. In the 4:1 gear ratio transmission test, the results obtained were 504.4 rpm turbine rotation, 2114.9 rpm generator rotation, 10.99 volt voltage, 4.43 amperes current, and 48.70 watt power.
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Han, S. Y., R. R. Taghavi, and S. Farokhi. "Numerical simulation of supersonic jet instability modes of plane and notched rectangular nozzles." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 226, no. 1 (September 29, 2011): 104–22. http://dx.doi.org/10.1177/0954406211413964.
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The effect of exit geometry of a rectangular nozzle on the instability modes and mixing characteristics of under-expanded supersonic jets is computationally investigated. The unsteady three-dimensional viscous simulation is based on the Proteus code developed at NASA Glenn Research Center. A shock adaptive grid generator was developed to enhance the shock simulation. The nozzle aspect ratio for both plane and notched rectangular nozzles in this study is 5.0 and the fully expanded jet Mach number is 1.526. For the case of a plane rectangular nozzle, the ‘flapping’ oscillations, which are extensively observed in schlieren flow visualization and reported in acoustic measurements, are also captured in the presented computations. The flapping frequency in experimental measurements (7400 Hz) is closely predicted in the presented computations (7500 Hz). The symmetrical instability mode is also observed as viewed from the nozzle’s small and large dimensions at twice the flapping frequency. For the notched rectangular nozzle, the flapping oscillations ceased and instead a spanwise oscillation mode was observed as viewed from the nozzle’s large dimension. The instantaneous mass flowrate at nine jet widths downstream of the nozzle exit showed an increase of 8.5 per cent in mass flowrate in the jet emerging from the notched as compared to the plane rectangular nozzle.
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Pushnov, A. S., E. Yu Baranova, and A. S. Sokolov. "Study of hydrodynamic characteristics of regular packing of the nozzle-shaped elements." Izvestiya MGTU MAMI 7, no. 3-2 (April 10, 2013): 99–105. http://dx.doi.org/10.17816/2074-0530-68056.
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The article presents the results of experimental investigations of the hydrodynamic characteristics of a regular packing of nozzle-shaped elements, the results of comparative analysis of different types of nozzles, showing that the studied nozzle has a more developed specific surface during hydraulic resistance comparable with the most common industrial nozzles.