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Статті в журналах з теми "Drop sizing methods"
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Löffler-Mang, M., K. D. Beheng, and H. Gysi. "Messung von Tropfengrößenverteilungen in Regen — ein Vergleich zweier Meßmethoden." Meteorologische Zeitschrift 5, no. 4 (September 18, 1996): 139–44. http://dx.doi.org/10.1127/metz/5/1996/139.
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Lima, João L. M. P. de, Valdemir P. Silva, M. Isabel P. de Lima, João R. C. B. Abrantes, and Abelardo A. A. Montenegro. "Revisiting simple methods to estimate drop size distributions: a novel approach based on infrared thermography." Journal of Hydrology and Hydromechanics 63, no. 3 (September 1, 2015): 220–27. http://dx.doi.org/10.1515/johh-2015-0025.
Повний текст джерелаАнотація:
Abstract The infrared thermography has been successfully applied as a tool for high resolution imaging in different hydrological studies. This exploratory experimental study aimed at evaluating the possibility of using infrared thermography to determine the diameter of raindrops. Rain samples are collected on a pre-heated acrylic board, which is exposed to rain during an instant, and thermograms are recorded. The area of the thermal stains (“signatures” of the raindrops) emerging on the board is measured and converted to drop diameters, applying a calibration equation. Diameters of natural raindrops estimated using this technique were compared with laser disdrometer measurements; the Nash-Sutcliffe efficiency coefficient was used for evaluating the match between the resulting histograms of drop size distribution. Results confirm the usefulness of this simple technique for sizing and counting raindrops, although it is unsatisfactory in light rain or drizzle.
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Brkić, Dejan. "Two Iterative Methods for Sizing Pipe Diameters in Gas Distribution Networks with Loops." Computation 12, no. 2 (February 1, 2024): 25. http://dx.doi.org/10.3390/computation12020025.
Повний текст джерелаАнотація:
Closed-loop pipe systems allow the possibility of the flow of gas from both directions across each route, ensuring supply continuity in the event of a failure at one point, but their main shortcoming is in the necessity to model them using iterative methods. Two iterative methods of determining the optimal pipe diameter in a gas distribution network with closed loops are described in this paper, offering the advantage of maintaining the gas velocity within specified technical limits, even during peak demand. They are based on the following: (1) a modified Hardy Cross method with the correction of the diameter in each iteration and (2) the node-loop method, which provides a new diameter directly in each iteration. The calculation of the optimal pipe diameter in such gas distribution networks relies on ensuring mass continuity at nodes, following the first Kirchhoff law, and concluding when the pressure drops in all the closed paths are algebraically balanced, adhering to the second Kirchhoff law for energy equilibrium. The presented optimisation is based on principles developed by Hardy Cross in the 1930s for the moment distribution analysis of statically indeterminate structures. The results are for steady-state conditions and for the highest possible estimated demand of gas, while the distributed gas is treated as a noncompressible fluid due to the relatively small drop in pressure in a typical network of pipes. There is no unique solution; instead, an infinite number of potential outcomes exist, alongside infinite combinations of pipe diameters for a given fixed flow pattern that can satisfy the first and second Kirchhoff laws in the given topology of the particular network at hand.
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Cai, Wenlu, Cherdpong Jomdecha, Yingsong Zhao, Li Wang, Shejuan Xie, and Zhenmao Chen. "Quantitative evaluation of electrical conductivity inside stress corrosion crack with electromagnetic NDE methods." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2182 (September 14, 2020): 20190589. http://dx.doi.org/10.1098/rsta.2019.0589.
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This paper presents a comparison of studies on the local distributed electrical conductivity in stress corrosion crack (SCC) from signals of eddy current testing (ECT) and direct current potential drop (DCPD) aiming to improve SCC sizing accuracy when using electromagnetic non-destructive testing (NDT) methods. Experimental setups of ECT and DCPD were established, respectively, to collect measurement signals due to artificial SCCs in a plate of austenitic stainless steel. The local conductivity in the SCC region was reconstructed from the feature parameters extracted from the measured ECT and DCPD signals through inverse analyses. The inversion strategies for ECT and DCPD, each including an efficient forward simulation and an optimization scheme, were introduced from the viewpoint of conductivity reconstruction. Inversion results obtained from the measured ECT and DCPD signals showed the consistent trend which proved the validity of the predicted electrical conductivity indirectly. It is clarified that the electrical conductivity in a SCC is relatively high at the crack tip area and may become as high as 17% of that of the base material. These results provide a good reference to enhance the sizing accuracy of SCC with an electromagnetic NDT method such as ECT by updating the conductive crack model based on the results of this work. This article is part of the theme issue ‘Advanced electromagnetic non-destructive evaluation and smart monitoring’.
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Singleton, E. W. "Development of a High-Performance Choke Valve with Reference to Sizing for Multiphase Flow." Measurement and Control 24, no. 9 (November 1991): 273–81. http://dx.doi.org/10.1177/002029409102400902.
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The paper describes events leading up to the development of a variable choke valve for high-pressure drop service on multiphase fluids. During the evolvement of the design, which has now been proved in service, it was found necessary to discard some of the accepted precepts and conventions of control valve design. This work also led to an investigation into the various methods of sizing valves for multiphase fluids. The results obtained from available methods were compared and a new method was devised which appears to maintain a higher level of accuracy over a wide range of multiphase flow conditions.
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Satyarnarayan, L., D. M. Pukazhendhi, Krishnan Balasubramaniam, C. V. Krishnamurthy, and D. S. Ramachandra Murthy. "Phased Array Ultrasonic Measurement of Fatigue Crack Growth Profiles in Stainless Steel Pipes." Journal of Pressure Vessel Technology 129, no. 4 (July 24, 2006): 737–43. http://dx.doi.org/10.1115/1.2767367.
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This paper reports experimental sizing of fatigue crack profiles that are initiated from artificially made circumferential starter notches in stainless steel pipes of 169mm outer diameter and 14.33mm thickness, which were subjected to cyclic bending loads in a four point bending load arrangement using two nondestractive evaluation (NDE) methods: (a) phased array ultrasonic technique and (b) alternating current potential drop technique. The crack growth estimated using the two NDE techniques were compared with the beach marks that were present in the fracture surface. A simulation study using the ray tracing method was carried out to model the ultrasonic wave propagation in the test specimen, and the results were compared with the experimental results.
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Gyürki, Dániel, Benjamin Csippa, György Paál, and István Szikora. "Impact of Design and Deployment Technique on the Hydrodynamic Resistance of Flow Diverters." Clinical Neuroradiology 32, no. 1 (October 22, 2021): 107–15. http://dx.doi.org/10.1007/s00062-021-01106-1.
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Abstract Purpose Despite the high efficacy of flow diverters (FD) in treating sidewall intracranial aneurysms, failures are reported. One of the physical factors determining efficacy is the flow reducing capacity of the FD that is currently unknown to the operator. Our aim was to measure the flow reducing capacity expressed as the hydrodynamic resistance (HR), the metallic surface area (MSA) and pore density (PD) of two different FD designs and quantitatively investigate the impact of sizing and the deployment technique on these parameters. Methods Altogether 38 Pipeline (Medtronic) and P64 (Phenox) FD‑s were implanted in holder tubes by a neurointerventionist in nominally sized, oversized and longitudinally compressed or elongated manners. The tubes were placed in a flow model with the flow directed across the FD through a side hole on the tube. HR was expressed by the measured pressure drop as the function of the flow rate. Deployed length, MSA and PD were also measured and correlated with the HR. Results Both PD and MSA changed with varying deployment length, which correlates well with the change in HR. Oversizing the device by 1 mm in diameter has reduced the HR on average to one fifth of the original value for both manufacturers. Conclusion This study demonstrates experimentally that different FD designs have different flow diverting capacities (HR). Parameters are greatly influenced by radial sizing and longitudinal compression or elongation during implantation. Our results might be useful in procedure planning, predicting clinical outcome, and in patient-specific numerical flow simulations.
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Kalioudjoglou, Loïck, Clément Bonneau, Vincent Melot, Bruno Auvity, Christophe Josset, and Yoann Merriaux. "Prediction or hydraulic performance of shell-and-tube heat exchanger: comparison of 1D and CFD-porous media approaches." MATEC Web of Conferences 240 (2018): 02008. http://dx.doi.org/10.1051/matecconf/201824002008.
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The present paper deals with Heat Exchanger sizing methods and offers a comparison between two of them: 1D global method and CFD porous media method. Following Prithiviraj et al. work [1], new developments are based on recent knowledge acquired on porous media, using a coupling strategy of a three-dimensional commercial code with an in-house code library. The distributed hydraulic resistance concept and the numerical model are briefly described and confronted with pressure drop measurements from an experimental E-type STHE setup (shell-and-tube heat exchanger) from the literature. The present paper will put into perspective capabilities and limits of each method with needs for heat exchanger rating. Flow rate repartition is calculated with CFD-porous media using Tinker’s current approach. This new analysis provides a complete comparison with 1D global method. It also reveals the major impact of leakage flow rate between baffle and tubes. The numerical estimation of pressure losses, consistent with experimental measurements of Halle et al. [2], implies that our future work will include thermal performance characterization and geometrical optimization.
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Martinez, Gabrielle L., Farzad Poursadegh, Gina M. Magnotti, Katarzyna E. Matusik, Daniel J. Duke, Benjamin W. Knox, Alan L. Kastengren, Christopher F. Powell, and Caroline L. Genzale. "Measurement of Sauter mean diameter in diesel sprays using a scattering–absorption measurement ratio technique." International Journal of Engine Research 20, no. 1 (December 19, 2018): 6–17. http://dx.doi.org/10.1177/1468087418819912.
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A new diagnostic for the quantification of Sauter mean diameter in high-pressure fuel sprays has been recently developed using combined optical and X-ray measurements at the Georgia Institute of Technology and Argonne National Laboratory, respectively. This diagnostic utilizes liquid scattering extinction measurements from diffuse back-illumination imaging, conducted at Georgia Tech, and liquid absorption measurements from X-ray radiography, conducted at Argonne’s Advanced Photon Source. The new diagnostic, entitled the scattering–absorption measurement ratio, quantifies two-dimensional distributions of path-integrated Sauter mean diameter, enabling the construction of the spatial history of drop size development within practical fuel sprays. This technique offers unique benefits over conventional drop-sizing methods in that it can be more robust in optically dense regions of the spray, while also providing high spatial resolution of the corresponding droplet field. The methodology for quantification of Sauter mean diameter distributions using the scattering–absorption measurement ratio technique has been previously introduced and demonstrated in diesel sprays using the Engine Combustion Network Spray D injector; however, a more detailed treatment of measurement uncertainties has been needed. In this work, we present a summary of the various sources of measurement uncertainty in the scattering–absorption measurement ratio diagnostic, like those due to the experimental setup, data processing methods, and theoretical assumptions, and assess how these sources of uncertainty affect the quantified Sauter mean diameter. The spatially resolved Sauter mean diameter measurements that result from the scattering–absorption measurement ratio diagnostic will be especially valuable to the engine modeling community for the quantitative validation of spray submodels in engine computational fluid dynamics codes. Careful evaluation and quantification of measurement uncertainties are important to support accurate model validation and to ensure the development of more predictive spray models.
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Grossmann, Wolf, Iris Grossmann, and Karl W. Steininger. "Solar electricity supply isolines of generation capacity and storage." Proceedings of the National Academy of Sciences 112, no. 12 (March 9, 2015): 3663–68. http://dx.doi.org/10.1073/pnas.1316781112.
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The recent sharp drop in the cost of photovoltaic (PV) electricity generation accompanied by globally rapidly increasing investment in PV plants calls for new planning and management tools for large-scale distributed solar networks. Of major importance are methods to overcome intermittency of solar electricity, i.e., to provide dispatchable electricity at minimal costs. We find that pairs of electricity generation capacity G and storage S that give dispatchable electricity and are minimal with respect to S for a given G exhibit a smooth relationship of mutual substitutability between G and S. These isolines between G and S support the solving of several tasks, including the optimal sizing of generation capacity and storage, optimal siting of solar parks, optimal connections of solar parks across time zones for minimizing intermittency, and management of storage in situations of far below average insolation to provide dispatchable electricity. G−S isolines allow determining the cost-optimal pair (G,S) as a function of the cost ratio of G and S. G−S isolines provide a method for evaluating the effect of geographic spread and time zone coverage on costs of solar electricity.
Дисертації з теми "Drop sizing methods"
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Bourrilhon, Thibaut. "Tuyère diphasique à jet de brouillard : application à la lutte contre les incendies et au refroidissement des procédés métallurgiques." Phd thesis, Grenoble 1, 2009. http://www.theses.fr/2009GRE10106.
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Les brouillards d'eau ont démontré leur excellente efficacité dans la lutte contre l'incendie. Le concept de tuyère à jet de brouillard permet de produire en continu un écoulement diphasique très finement dispersé (très grande aire interfaciale). Pour cela on réalise un mélange effervescent d'eau et de gaz sous pression (3 à 10 bars). Le mélange est détendu dans une tuyère de géométrie (profil) adaptée. Au cours de cette détente le gaz fournit un travail qui assure d'une part la propulsion du liquide et d'autre part son fractionnement en fines gouttelettes. L'écoulement sortant se présente alors sous forme d'un jet de brouillard rapide (50 à 150 m/s). L'objectif de ces travaux est le développement de modèles pour décrire la détente de l'écoulement en tuyère et le jet libre formé au-delà de la section de sortie. Différents instruments de mesure (granulométre, vélocimétre) sont mis en oeuvre pour permettre une confrontation avec les simulations numériquesHigh velocity spray-jets have demonstrated their high efficiency in fire fighting. The concept presented here comprises a two-phase flow nozzle that directly expands a liquid-gas mixture (water + compressed-air). These two components are mixed, almost at rest, at the pressure of a conventional industrial networks (5 to 10 bars). The nozzle design is such that the exit jet presents two characteristics : high velocity and very fine dispersion. The aim of this work is to develop models to describe the flow expansion into the nozzle and the free jet developped downstream the exhaust section. Various measuring instruments (droplet size, velocity) are implemented to allow a comparison with numerical simulations
Тези доповідей конференцій з теми "Drop sizing methods"
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Wang, Xiaojuan, Shejuan Xie, Xiaowei Wang, and Zhenmao Chen. "Sizing of cavity defect in metallic foam from DC potential drop signals with stochastic inversion methods." In 2013 Far East Forum on Nondestructive Evaluation/Testing: New Technology & Application (FENDT). IEEE, 2013. http://dx.doi.org/10.1109/fendt.2013.6635528.
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Heydari, Ali, Pardeep Shahi, Vahideh Radmard, Bahareh Eslami, Uschas Chowdhury, Satyam Saini, Pratik Bansode, Harold Miyamura, Dereje Agonafer, and Jeremy Rodriguez. "Liquid to Liquid Cooling for High Heat Density Liquid Cooled Data Centers." In ASME 2022 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/ipack2022-97416.
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Abstract Removal of heat is becoming a major challenge in today’s data centers. Computing-intensive applications such as artificial intelligence and machine learning are pushing data center to compute intensive systems, such as GPU, CPU, and switches to their extreme limits. Racks of IT can approach up to 100kW of heat dissipation challenging traditional data center designs for enterprises and cloud service providers. Direct-to-chip liquid cooling utilizing cold plates is becoming a common method of removing heat from high heat density data center server racks. There are various methods of applying liquid cooling to data centers to address the high heat density components such as liquid to liquid (L2L), liquid to air (L2A), and liquid to single phase refrigerant (L2R). This study aims to investigate the thermo-hydraulic performance of the L2L cooling systems using cooling distribution units (CDUs). CDUs provide a cold secondary coolant (Propylene Glycol 25%) into the cooling loops of liquid-cooled server racks, with the CDUs providing liquid to liquid heat exchange between the primary facility water and secondary liquid used for cold plates. This study uses Thermal Test Vehicles (TTVs) which have been built to reproduce and simulate high heat density servers. Four different cooling loops are characterized experimentally, and detailed analytical and numerical simulations using CFD are developed for analyzing the cooling characteristics of the entire L2L cooling loop, including the CDU, for removing heat from the cold plates. Detailed Flow Network Modeling (FNM) has been performed to analyze precise hydraulic modeling of the secondary fluid flow, from the CDUs to the cooling loops, for predicting pressure drop and flow rate of the secondary coolant. A FNM properly sizes the pumping requirements of the L2L cooling system. Additionally, a system calculator has been created for quickly sizing all secondary loop piping for L2L heat exchanger deployments.
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Davies, Hywel, Midhat Talibi, Martin Hyde, and Ramanarayanan Balachandran. "Investigating Ethanol-Gasoline Spray Characteristics Using an Interferometric Drop Sizing Technique." In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-91421.
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Abstract To reduce reliance on fossil fuels there has been a global push to minimise fuel consumption, and incorporate the use of bio-derived fuels. In practical combustion systems that use liquid fuels, observing the spray behaviour of these biofuels is key in understanding fuel performance; in particular, droplet size distribution is known to have a strong influence on the fuel energy release and pollutant formation processes. This paper is aimed at the use of the TSI Global Sizing Velocimetry (GSV) interferometric technique as a method to gain detailed understanding of droplet number and size distribution, with a particular focus on ethanol-gasoline fuel blends. The imaging system for the GSV technique consisted of a Nd:YAG laser and a 4 MP (million pixel) camera, and the spray was generated using a generic automotive port fuel injector. The results showed that the GSV technique was able to effectively measure droplet concentration and diameters for all the fuel blends tested in this study. Ethanol was observed to have larger droplet diameters (both D10 and D32) as compared to fossil gasoline, with droplet diameters generally increasing as the proportion of ethanol in the gasoline was increased. The droplet concentration reduced with increasing radial distance from the spray centreline, but no appreciable change was observed with axial displacement from the nozzle tip. Degradation in the image quality was observed for fuel blends with less than 40% ethanol content. The GSV drop sizing measurements were validated using a mono-disperse droplet generator, and an excellent agreement (within 2%) was observed.
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Takeo, Fumio, Masumi Saka, Seiichi Hamada, and Manabu Hayakawa. "DC Potential Drop Technique Selecting Probes Distances Properly for Sizing Deep Surface Cracks." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-79877.
Повний текст джерелаАнотація:
D-C potential drop (DCPD) technique is a powerful tool for quantitative NDE of cracks. The technique using four probes which are in close proximity to each other has been proposed for NDE of surface cracks; that is the closely coupled probes potential drop (CCPPD) technique. It has been shown that the sensitivity of CCPPD technique to evaluate a small crack is enhanced significantly in comparison with the usual method. On the other hand, since CCPPD technique has been developed to evaluate a small crack sensitively, it is not fit to evaluate deep cracks which are sometimes found in the structural components of power plants. The objective of this study was to enhance the sensitivity of evaluating deep surface cracks. By extending the distance between current input and output probes, the change in potential drop with the change in the depth of deeper crack becomes large. But the voltage of potential drop becomes small to measure, because the current density in the material becomes low. The voltage of the potential drop can be increased by increasing the applying current, but the current would also be limited by the equipment or contacting probes. Then the way to select the appropriate distances between probes from the viewpoints of the sensitivity and the required current has been shown.
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Park, Nam Su, Yu Dong Kim, and Sang Yong Lee. "Improvement of Measurement Accuracy of Laser Diffraction Method in Sizing Spray Particles." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32527.
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Drop size measurement is an important part in studying atomization characteristics and spray behavior. Recently, the laser diffraction method that does not interrupt the spray flow is being widely used. In the present study, a set of reticles (reference particles) with known size distributions, based on the Rosin-Rammler distribution function, were used to evaluate the measurement accuracy of the laser diffraction method. Experimental results showed that Sauter mean diameters (SMD) measured with a laser diffraction particle analyzer were in good agreement with the true values for the entire range of the Rosin-Rammler distribution parameters tested. However, the dispersion parameters in the Rosin-Rammler function were measured to be considerably different from the actual ones, as the particle distribution became monodispersed. Thus, functional expression for the parameter representing the dispersion was proposed in terms of the peak height ratio obtained directly from the light energy distribution information.
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Vijiapurapu, Sowjanya, Jie Cui, and Sastry Munukutla. "CFD Applications for Coal/Air Balancing in Power Plants." In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-55098.
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A new method for balancing coal / air flow to individual burners connected to a mill in a pulverized coal fired unit was proposed. A generalized calculation procedure based on this method was developed for sizing the orifices needed for balancing the coal / air flow. Efficient use of commercially available computational fluid dynamics (CFD) software was suggested for the calculation of the pressure drop in pipes with unclear specifications of geometries. The current industry practice is to balance the clean air flow and accept the resulting imbalance in the coal / air flow. By this new method the clean-air flow would be unbalanced in a tailored manner so that balanced coal / air flow would result. In order to implement this new method the power plants would still have to conduct clean air tests only.
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O¨zkol, Ibrahim, and Serhat Celik. "Optimum Size Determination for Air Cooled Heat Exchanger (ACHE) via Genetic Algorithm." In ASME/JSME 2004 Pressure Vessels and Piping Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/pvp2004-3089.
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Sizing an air-cooled heat exchanger requires tedious, time-consuming calculations to balance air and liquid heat-transfer properties according to the temperature requirements. There are some constraints to make the design better. The airside pressure drop (ΔPa) and the number of heat transfer units (NTU) are two of them. The minimum ΔPa requires the minimum fan power. As a result of this the operational cost can be minimized. In some environmental conditions the noise can be minimized too. NTU includes the size of the heat exchanger and fluid heat transfer capacities. It is very important for producer to drop the cost of production and logistic. Imagining the transport of hundreds goods make us understand the importance of this parameter easily. There are a lot of work in literature to make the design of air-cooled heat exchanger easy. But most of them have irreversible calculations and all the calculations should be carried out many times till getting the acceptable results. These trial and error calculation require much time. To overcome such difficulties, today, in many engineering problems there is a mass application of heuristic algorithms. The most common of these is genetic algorithms. The design of an optimum heat exchanger is a formidable challenge for designers. First, such a design involves a large number of parameters to be optimized. It is almost impossible to find an optimum design by the traditional “trial and error” method. Second, design is usually a multi objective and multi-point problem that simultaneously has to content with a variety of design criteria. In this study, we obtained accurate and robust answers in a few minutes by developping a computer code using genetic algorithm. It is also possible to find the optimum size of any heat exchanger by making required changes in the code according to the type of heat exchangers.
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Chishty, Wajid A., Michael R. Brady, Noah H. Schiller, Pavlos P. Vlachos, and Uri Vandsburger. "Quantification of Modulated Spray Dynamics by Time-Resolved DPIV." In ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56835.
Повний текст джерелаАнотація:
This effort presents the application of an experimental high frequency and time-resolved global optical flow diagnostics for the characterization of pulsed spray flows. Such flows are encountered during active control of thermoacoustic instabilities, where high-bandwidth fuel modulation is often utilized to disrupt the combustor acoustic and unsteady heat release coupling. The understanding of spray dynamics is thus of paramount importance for these active control methodologies in order to achieve optimum control authority. A novel time-resolved Digital Particle Image Velocimetry (TRDPIV) implementation is employed for the dynamic investigation of the modulated spray. The method can measure both the droplet velocities as well as the droplet size distribution, from the same recorded images. The method provides planar image based droplet sizing using Mie scattering from DPIV measurements, with >5KHz sampling rate. Thus, eliminating complicated experimental approaches based on interferometer or fluorescence-Mie ratio. This paper presents the results of drop size characterization. Data processing is performed using different particle size evaluation schemes. The results are compared with measurements acquired from Phase Doppler Anemometry (PDA), conducted under same the experimental conditions. Experiments are conducted in non-reacting quiescent conditions, using an industrial simplex nozzle. The proportional spray modulation is obtained using a throttle valve-piezoelectric stack actuation system. The measurements for the current DPIV work are obtained under different pulsing amplitudes and frequencies. The results indicate that time-resolved DPIV can be a valuable tool in investigating dynamic response of modulated sprays.
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Igi, Satoshi, Satoru Yabumoto, Masaki Mitsuya, Yuya Sumikura, and Mikihiro Takeuchi. "Full Gas Burst Test for HFW Linepipe at Low Temperature." In 2014 10th International Pipeline Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/ipc2014-33326.
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A full gas burst test at low temperature below −40°C was performed using a high frequency welded (HFW) linepipe with high-quality weld seam, “MightySeam®,” [1–4] in order to verify the applicability of the Drop Weight Tear Test (DWTT). Residual stress exists in the pipe body of HFW linepipe because the manufacturing method includes a sizing process. Therefore, it is necessary to clarify the difference between the arrestability in the DWTT without residual stress in the specimen and that in the full gas burst test with residual stress in the pipe body. The full gas burst test is performed using a test pipe specimen in which a notch is introduced into the base material by an explosive cutter. In addition, a test pipe specimen with a notch introduced into the weld seam was used in this study because the developed HFW linepipe, “MightySeam®,” has excellent low-temperature toughness as a result of control of the morphology and distribution of oxides generated in the welding process by temperature and deformation distribution control. The Charpy transition temperature of “Mighty Seam®” was much lower than −45 °C. Ductile cracks were initiated from the initial explosive notch, and these cracks were arrested after ductile crack propagation of about 1 m in base material on both sides. The fracture behavior was similar in appearance in the DWTT without residual stress and the full gas burst test with residual stress.
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Bose, Rana. "Integrating Isolation Valve Specifications Into Supercritical Power Plant Piping Design Specifications." In ASME 2016 Power Conference collocated with the ASME 2016 10th International Conference on Energy Sustainability and the ASME 2016 14th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/power2016-59081.
Повний текст джерелаАнотація:
Clean and cost effective super critical power plants (SCPP) require “whistle clean” conditions, low emissions, low noise, higher velocities and flow rates. A majority of the specification packages for valves are developed by experienced piping engineers, assigned to EPCs and the valve section comprises a relatively small element where references to industrial standards like ASME B16.34 or ANSI B31.1 are made for design and stress parameters. The specific valve data sheets then provide some more information as to operating and boundary conditions for the specific valves. With the increasing prevalence of SCPP requirements, the current specifications made available by EPCs, make it somewhat enigmatic for valve designers and manufacturers to address the concerns of the power plant designers and engineers. This is in terms of valve bores, pressure drops, velocities, thermal fatigue, lowered valve weights and acceptable sound levels that are intrinsic to valve design, sizing and optimization. This paper presents some specific examples where flows, velocities, pipe ID and valve bore are compared to enable a better integration of piping characteristics in relationship to safe valve design, without unnecessarily over-specifying. In addition, suggestions have been made for an understanding of the relatively newer piping and valve materials for high temperature, high pressure applications, where alternative design methods would enable lower costs and greater resilience to thermal binding and fatigue.