Journal articles: 'Cold spray nozzles'

1

Vadla, Sai Rajkumar, and Jeffrey Doom. "Analysis of Jet Characteristics Among Various Cold Spray Nozzles." Journal of Thermal Spray and Engineering 1, no. 1 (2018): 24–31. http://dx.doi.org/10.52687/2582-1474/115.

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This research is conducted mainly to analyze the jet characteristics of various cold spray nozzles. This study presents the theoretical and practical aspects of Cold Spray process modeling, discusses multiple numerical analysis research areas, and determines the significant parameters to be considered while developing a custom cold spray setup and exhibits analysis-based correlations. The simulations were performed on some meshes of different density using the SST turbulent model in Star CCM+ solver. For the first time, in this work, the jet characteristics inside a step drilled nozzle was presented; Furthermore, shock diamond formation was found inside the divergent section of step drilled nozzle which strongly influence the flow regime with sharp fluctuations. The comprehensive comparison between step drilled nozzle, conical nozzle and curved nozzle indicates that curved nozzle results in slightly higher nozzle exit velocity. However, results have suggested that the curved nozzle can achieve much higher velocities by optimizing the nozzle length.

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Lupoi, R., and W. O'Neill. "Powder stream characteristics in cold spray nozzles." Surface and Coatings Technology 206, no. 6 (December 2011): 1069–76. http://dx.doi.org/10.1016/j.surfcoat.2011.07.061.

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Hu, W. J., K. Tan, S. Markovych, and X. L. Liu. "Study of a Cold Spray Nozzle Throat on Acceleration Characteristics via CFD." Journal of Engineering Sciences 8, no. 1 (2021): F19—F24. http://dx.doi.org/10.21272/jes.2021.8(1).f3.

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Cold spray technology can obtain coatings in a solid state, suitable for deposition protection, repair, and additive manufacturing. In order to further expand the application areas of cold spraying nozzles, especially the inner surface of the components or areas where a Straight-line conical nozzle cannot be applied, because the study of the throat of the nozzle with the angle will directly reduce the total length of the nozzle (the horizontal direction), hence, the spray with the angle will show its advantage. This study discusses the influence of the throat structure of the conical cold spray nozzle on the acceleration characteristics, including the throat’s size, length, and angle. The results show the following. Firstly, under the premise of keeping the shrinkage ratio and divergence ratio unchanged at normal temperature, the throat diameter is between 2–6 mm in size, and the maximum growth rate exceeds 20 m/s. When the throat exceeds 6mm, the growth rate of the outlet slows down, and the growth rate is only 8 m/s. Secondly, the length of the throat has little effect on the acceleration characteristics, the total range fluctuated from 533 to 550 m/s, and 11 mm length of the throat is the closest to 0mm. Additionally, the 90° throat angle has the least effect on the acceleration characteristics. Finally, the particle trajectory is affected by inlet pressure, injection pressure, particle size, and other factors.

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Meyer, M., and R. Lupoi. "An analysis of the particulate flow in cold spray nozzles." Mechanical Sciences 6, no. 2 (August 11, 2015): 127–36. http://dx.doi.org/10.5194/ms-6-127-2015.

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Abstract. Cold Spray is a novel technology for the application of coatings onto a variety of substrate materials. In this method, melting temperatures are not crossed and the bonding is realized by the acceleration of powder particles through a carrier gas in a converging-diverging nozzle and their high energy impact over a substrate material. The critical aspect of this technology is the acceleration process and the multiphase nature of it. Three different nozzle designs were experimented under constant conditions and their performance simulated using Computational Fluid Dynamics tools. The Deposition Efficiency was measured using titanium as feedstock material and it was shown that it decreases with the cross-sectional throat area of the nozzle. Computational results based on a one-way coupled multiphase approach did not agree with this observation, while more sophisticated modelling techniques with two-way couplings can partially provide high-quality outcomes, in agreement with experimental data.

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Liu, Ruoxin, Rui Zhao, Yongle Nian, and Wenglong Cheng. "Experimental study on the effect of additives on the heat transfer performance of spray cold plate." Journal of University of Science and Technology of China 52, no. 1 (2022): 4. http://dx.doi.org/10.52396/justc-2021-0152.

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<p>The spray cold plate has a compact structure and high-efficiency heat exchange, which can meet the requirements of high heat flux dissipation of multiple heat sources, and is a reliable means to solve the heat dissipation of the next generation of chips. This paper proposes to use surfactants to enhance the heat transfer of the spray cold plate, and conduct a systematic experimental study on the heat transfer performance of the spray cold plate under different types and concentrations of additives. It was found that among the three surfactants, sodium dodecyl sulfate (SDS) can improve the heat transfer performance of the spray cold plate, and at the optimal concentration of 200ppm, the heat transfer coefficient of the spray cold plate was increased significantly by 19.8%. Both the n-octanol-distilled water and Tween 20-distilled water can reduce the heat transfer performance of the cold plate using multi nozzles. In addition, based on the experimental data, the dimensionless heat transfers correlations for the spray cold plate using additives were conducted, and the maximum errors of dimensionless correlations for using additives were 2.1%, 2.8%, and 5.4% respectively. This discovery provides a theoretical analysis and basis for the improvement of spray cold plates.</p>

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Cao, Congcong, Wenya Li, Zhengmao Zhang, Xiawei Yang, and Yaxin Xu. "Cold Spray Additive Manufacturing of Ti6Al4V: Special Nozzle Design Using Numerical Simulation and Experimental Validation." Coatings 12, no. 2 (February 6, 2022): 210. http://dx.doi.org/10.3390/coatings12020210.

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Cold spray additive manufacturing (CSAM) shows great potential in titanium-alloy production as it is a solid-state process. However, data published so far have demonstrated the difficulty of producing dense and high-strength Ti alloy parts. Our previous studies have shown that nozzle design together with high-cost helium propulsive gas plays a crucial role in particle acceleration. In this work, special nozzles for Ti alloy were designed and validated experimentally with commercially available Ti6Al4V powder. Simulation results show that particle impact temperature increases remarkably for a long convergent length, while particle kinetic energy slightly increases, which is validated by experiments. The relationship between the particle impact temperature and practice diameter shows the first increase and then decrease. The experimental results show that as the nozzle convergent section becomes longer, the edges of the single-pass deposits become smoother, and the width, density, deposition efficiency, and microhardness of the single-pass deposits increase.

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Lupoi, Rocco, Morten Meyer, Wessel W. Wits, and Shuo Yin. "The role of particles flow characteristics in the performance of cold spray nozzles." CIRP Annals 69, no. 1 (2020): 189–92. http://dx.doi.org/10.1016/j.cirp.2020.04.061.

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Liebersbach, Piotr, Alden Foelsche, Victor K. Champagne, Matt Siopis, Aaron Nardi, and David P. Schmidt. "CFD Simulations of Feeder Tube Pressure Oscillations and Prediction of Clogging in Cold Spray Nozzles." Journal of Thermal Spray Technology 29, no. 3 (February 2020): 400–412. http://dx.doi.org/10.1007/s11666-020-00992-0.

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Tanigoshi, L. K., and Hugo Aguilar. "Control of Twospotted Spider Mite on Azuki Bean, 1992." Insecticide and Acaricide Tests 18, no. 1 (January 1, 1993): 191. http://dx.doi.org/10.1093/iat/18.1.191.

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Abstract Seven chemicals and 1 combination were evaluated for control of TSSM at the Irrigated Agriculture Research and Extension Center, Prosser, Benton County, WA. Spray treatments were applied with a CO2-powered backpack sprayer calibrated to delivery 25 gal/acre at 60 psi from a 7.5 ft boom with 8 TXVS-8 conejet nozzles. A completely randomized design was used with 0.01 acre plots replicated 5 times. Treatments were applied on 19 Aug. TSSM females were sampled by randomly selecting 20 leaflets/plot. Leaflets were placed in paper bags and kept in a cold box until processed with a mite brushing machine. Plots were visually examined for evidence of phytotoxicity.

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Özdemir, Ozan Çağatay, Joseph Mitchell Conahan, and Sinan Müftü. "Particle Velocimetry, CFD, and the Role of Particle Sphericity in Cold Spray." Coatings 10, no. 12 (December 18, 2020): 1254. http://dx.doi.org/10.3390/coatings10121254.

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Implementation of the cold spray (CS) technology in manufacturing and repair creates a demand for reliable quality control and process monitoring measures. In this regard, particle size and impact velocity are undoubtedly the most important control parameters in CS. Several in-flight measurement systems for particle velocimetry are now available commercially for CS. These systems provide great potential to be used as a diagnostic tool for validating CS system performance in industrial applications. However, post processing the velocimetry data is required in many instances for achieving a complete understanding of the particle flow field. In this study, particle velocimetry is used in conjunction with computational fluid dynamics (CFD) simulations to: (i) identify the physical factors that dictate the particle velocity and its variability; (ii) develop high fidelity CFD models to accurately predict particle flight parameters that cannot be measured by available experimental tools; and (iii) present the capabilities of state-of-the-art velocimeters as a reliable diagnostic tool for measuring the consistency and repeatability of CS systems in manufacturing settings. In-flight particle size, location, and velocity are measured using a commercially available velocimeter for aluminum and copper particles sprayed with supersonic nozzles using helium, nitrogen, and air by two high pressure CS systems. As a result of this work, particle sphericity was clearly identified to have strong effects on particle velocity and to be one of the main factors of the variability of particle velocity. Furthermore, methods for building a high-fidelity 3D-CFD model was presented. CFD models were validated using particle velocimetry and schlieren imaging. Finally, particle velocimetry is shown to be a valid diagnostics tool for CS with systems capable of measuring in-flight particle velocities along with particle sizes. This article also outlines steps necessary for conducting cold spray process diagnostics repeatably and reliably.

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Alhulaifi, Abdulaziz S., and Gregory A. Buck. "Characterization of the interacting gas-particle dynamic system in cold spray nozzles in dimensional and non-dimensional form." Powder Technology 338 (October 2018): 325–32. http://dx.doi.org/10.1016/j.powtec.2018.07.032.

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Lupoi, R. "Current design and performance of cold spray nozzles: experimental and numerical observations on deposition efficiency and particle velocity." Surface Engineering 30, no. 5 (December 19, 2013): 316–22. http://dx.doi.org/10.1179/1743294413y.0000000214.

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13

Zhao, Le, Yu Zhang, Yuanjiang Pei, Anqi Zhang, and Muhsin M. Ameen. "Numerical Optimization of Spray-Guided Spark Assistance for Cold Idle Operation in a Heavy-Duty Gasoline Compression Ignition Engine." Energies 16, no. 2 (January 5, 2023): 637. http://dx.doi.org/10.3390/en16020637.

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This article describes the results of a response surface model (RSM)-based numerical optimization campaign for spray-guided spark assistance at cold operations in a heavy-duty gasoline compression ignition (GCI) engine. On the basis of an earlier work on spark-assisted GCI cold combustion, a space-filling design of experiments (DoE) method was first undertaken to investigate a multitude of hardware design variables and engine operating parameters. The main design variables included the number of injector nozzles, fuel split quantities and injection timings, and spark timing. The objective variables were engine combustion efficiency (ŋc), maximum pressure rise rate (MPRR), and engine-out nitrogen oxide (NOx) emissions. A total of 150 design candidates were automatically generated using the Sobol sequence method provided by the commercial software package, CAESES. Then, closed-cycle computational fluid dynamic (CFD) spark-assisted GCI simulations under cold idling operations were performed. The outcomes from the CFD-DoE design campaign were utilized to construct high-fidelity RSMs that allowed for further design optimization of the spark plug- and fuel injector-related design variables, along with fuel injection strategy parameters. A merit function with respect to objective variables was formulated with an appropriate weight assignment on each objective variable. Finally, the best design candidate was identified from the RSM-based optimization process and further validated in the CFD analysis. The best design candidate showed the potential to significantly improve combustion efficiency (ŋc > 90%) over the baseline at cold idle while satisfying MPRR and NOx emissions constraints (MPRR < 5 bar/CAD and NOx < 4.5 g/kWh).

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Kominek, Jan, Tomas Luks, Michal Pohanka, and Jong-Yeon Hwang. "Influence of Segmented Rolls on Homogeneity of Cooling in Continuous Casting." Metals 11, no. 8 (August 2, 2021): 1232. http://dx.doi.org/10.3390/met11081232.

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This paper deals with secondary cooling in a continuous caster. In particular, it deals with cooling inhomogeneity caused by spray arrangement and segmented rolls used for leading the strand. The cooling section is placed under the mold. Segmented rolls are supported by bearings in several places across the strand. Sprayed water can flow in the gaps between rolls where the bearing pocket is located. The main question that was experimentally studied is how this geometry with segmented rolls can influence homogeneity of cooling. Two experimental approaches developed for this study were applied, and both used full-scale geometrical configuration. The first one was a cold test where water flow and water distribution were observed using a transparent board with the studied surface structures (rollers and bearing pockets) and four spraying nozzles. The second one was a cooling test using a heated steel plate with rolls and bearing pockets. Cooling homogeneity was studied based on the temperature distribution on the rear side of the sample, which was recorded using an infrared camera. Homogeneity of cooling distribution was experimentally studied for three levels of cooling intensity that are used in typical cooling sections in plants. The hot tests showed that the bearing pockets do not provide significant cooling inhomogeneity despite the fact that a large amount of water flows through the gap between the rollers (which has been observed in cold tests).

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Ramadhan, Muhamad Ikhsan, Jojo Sumarjo, Farradina Choria Suci, and Deri Teguh Santoso. "ANALISIS KERUSAKAN MESIN AHU MENGGUNAKAN PENDEKATAN METODE FAILURE MODE AND EFFECT ANALYSIS." ROTOR 14, no. 2 (November 22, 2021): 49. http://dx.doi.org/10.19184/rotor.v14i2.26460.

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The manufacturing industry is currently experiencing rapid development from various aspects. This aspect develops, it is increasingly necessary to find solutions to get more effective and efficient results. The Air Handling Unit (AHU) machine is a heat exchanger between cold water and air. The method used to identify the damage is the Failure Mode and Effect Analysis (FMEA) method. With this method, it is hoped that the point of damage that occurs can be known and can be planned for further maintenance. The results of the analysis of the FMEA method were obtained from related fields regarding the damage to the AHU engine components. Based on the results of the analysis of the Pareto diagram, it can be seen that there are several types of damage that dominant in the Air Handling Unit engine, namely; Motors & blowers; Pipe; Air Filter; Spray Nozzles. According to the principle of the Pareto diagram, which is 80/20, it means that 80% of damage to the machine is caused by 20% of the causes of damage. In this case damage the motor & blower, pipelines, air filters must be prioritized for maintenance so that the quality and efficiency of the engine is getting better.

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Chocholousek, Michal, David Bricín, and Zbynek Spirit. "Heat Treatment Influence on Mechanical Properties of Nickel Based Cold Spray." MATEC Web of Conferences 367 (2022): 00005. http://dx.doi.org/10.1051/matecconf/202236700005.

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The article deals with evaluation of Ni and NiCr Cold Spray layers as a potential method for repairing components in energy industry by replacing or refilling flawed material. Cold spray layers from two NiCr powders of different particle sizes sprayed with nozzle for inner tube application and from Ni powder of one particle size sprayed with different nozzle types – for inner and outer tube applications – were tested. The evaluation is aimed on mechanical properties and metallographic analysis of cold spray layers as received and after defined heat treatments. It summarizes tensile properties at room temperature and microstructure of used powders and final cold spray layers. Ultimate tensile strength, hardness and plastic elongation are evaluated from the mechanical point of view. Metallographic analysis is focused on ovality and size of particles in powders and of splats in final cold sprays. Porosity of sprayed layers is evaluated on tested specimens.

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Jodoin, B. "Cold Spray Nozzle Mach Number Limitation." Journal of Thermal Spray Technology 11, no. 4 (December 1, 2002): 496–507. http://dx.doi.org/10.1361/105996302770348628.

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Nasif, Gus, R. M. Barron, Ram Balachandar, and Julio Villafuerte. "Numerical assessment of miniaturized cold spray nozzle for additive manufacturing." International Journal of Numerical Methods for Heat & Fluid Flow 29, no. 7 (July 1, 2019): 2277–96. http://dx.doi.org/10.1108/hff-10-2018-0553.

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Purpose Application of cold spray technology may exhibit significant benefits for the additive manufacturing process, particularly for producing intricate objects. To ascertain the feasibility of such an application, this paper aims to present a numerical investigation of the effect of scaling down a convergent-divergent (de Laval) nozzle, which is typically used in the cold spray industry, on the compressible flow parameters and thermal characteristics. Design/methodology/approach The Navier–Stokes equations and energy equation governing compressible flow are numerically solved using a finite volume method with a coupled solver. The conjugate heat transfer technique is used to couple fluid and solid heat transfer domains and predict the local heat transfer coefficient between the solid and fluid. The use of various RANS turbulence models has also been investigated to quantify the effect of the turbulence model on the simulation. Findings The numerical results reveal that the flow and thermal characteristics are altered as the convergent-divergent nozzle is scaled down. The static pressure and temperature profiles at any section in the nozzle are shifted toward higher values, while the Mach number profile at any section in the nozzle is shifted toward a lower Mach number. The turbulent kinetic energy at the nozzle exit increases with the scaling down of the nozzle geometry. This study also provides convincing evidence that the adiabatic approach is still suitable even though the temperature of the nozzle wall is extremely high, as required for industrial application. Results indicate that it is feasible to use the available capabilities of the cold spray technology for additive manufacturing after scaling down the nozzle. Originality/value The idea of adopting cold spray technology for additive manufacturing is new and innovative. To develop this idea into a viable commercial product, a thorough understanding of the flow physics within a cold spray nozzle is required. The simulation results discussed in this paper demonstrate the effect that scaling down of a convergent-divergent nozzle has on the flow characteristics in the nozzle.

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Liu, Chuan Shao, Jiang Wei Cheng, and Jian Xin Zheng. "Numerical Simulation of Gas-Particle Two Phase Flow in the Process of Cold Spraying Aluminum Zinc-Base Alloy Powder." Applied Mechanics and Materials 37-38 (November 2010): 735–38. http://dx.doi.org/10.4028/www.scientific.net/amm.37-38.735.

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The gas velocity and particle velocity in and out of the nozzle have great influence on the coating effect in the process of cold spray. An axis-symmetric two-dimensional mathematical model was presented to study the flow field in and out of cold spray nozzle, and the effect of different pressure, temperature, spraying distance and particle diameter on gas axial velocity and particle velocity were researched. The simulation results showed that the gas axial velocity and particle velocity increased when the gas pressure and temperature were increased, spray distance had little effect on the flow field in the nozzle, and small diameter particle was more easily accelerated.

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Matts, Olga, Hussein Hammoud, Alexey Sova, Zineb Bensaid, Guillaume Kermouche, Helmut Klöcker, Cédric Bosch, and Nathalie Texier-Mandoki. "Influence of Cold Spray Nozzle Displacement Strategy on Microstructure and Mechanical Properties of Cu/SiC Composites Coating." Key Engineering Materials 813 (July 2019): 110–15. http://dx.doi.org/10.4028/www.scientific.net/kem.813.110.

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In this work an influence of cold spray nozzle displacement parameters on the properties of copper-silicon carbide cold spray deposits is considered. In particular the influence of nozzle traverse speed and distance between deposited tracks on the coating porosity and behavior during compressive tests was analyzed. It was shown that cold spraying at low nozzle traverse speed leads to formation of thick tracks with quasi-triangular cross-section. As a consequence, the particle impact angle on the sides of spraying track increases that. Thus, the particle deformation at impact on the track periphery becomes insufficient and local porosity value rises. Increase of nozzle traverse speed allows increasing coating density and mechanical properties due to amelioration of particle deformation conditions. Compressive tests revealed significant anisotropy of mechanical properties of copper-silicon carbide cold spray deposits. In particular, compressive strength measured in vertical direction (perpendicular to the substrate) was significantly higher than one measured in horizontal plane (parallel to substrate). This anisotropy could be explained by the orientation of particle deformation pattern during impact.

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Alkhimov, A. P., V. F. Kosarev, and S. V. Klinkov. "The Features of Cold Spray Nozzle Design." Journal of Thermal Spray Technology 10, no. 2 (June 1, 2001): 375–81. http://dx.doi.org/10.1361/105996301770349466.

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Iyo, Toru, Keiko Asakura, Makiko Nakano, Mutsuko Yamada, and Kazuyuki Omae. "Bidet toilet seats with warm-water tanks: residual chlorine, microbial community, and structural analyses." Journal of Water and Health 14, no. 1 (August 20, 2015): 68–80. http://dx.doi.org/10.2166/wh.2015.057.

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Despite the reported health-related advantages of the use of warm water in bidets, there are health-related disadvantages associated with the use of these toilet seats, and the bacterial research is sparse. We conducted a survey on the hygienic conditions of 127 warm-water bidet toilet seats in restrooms on a university campus. The spray water from the toilet seats had less residual chlorine than their tap water sources. However, the total viable microbial count was below the water-quality standard for tap water. In addition, the heat of the toilet seats' warm-water tanks caused heterotrophic bacteria in the source tap water to proliferate inside the nozzle pipes and the warm-water tanks. Escherichia coli was detected on the spray nozzles of about 5% of the toilet seats, indicating that the self-cleaning mechanism of the spray nozzles was largely functioning properly. However, Pseudomonas aeruginosa was detected on about 2% of the toilet seats. P. aeruginosa was found to remain for long durations in biofilms that formed inside warm-water tanks. Infection-prevention measures aimed at P. aeruginosa should receive full consideration when managing warm-water bidet toilet seats in hospitals in order to prevent opportunistic infections in intensive care units, hematology wards, and other hospital locations.

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Majhool, Ahmed Abed Al-Kadhem, and Noor Mohsin Jasim. "Prediction of the Initial Drop Size and Velocity Distribution in the Cold Cryogenic Spray." International Journal of Heat and Technology 38, no. 3 (October 15, 2020): 629–40. http://dx.doi.org/10.18280/ijht.380307.

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The polydispersed nature of the spray is captured through the use of probability density functions based on the maximum entropy method to stand for the complete atomization characteristics of spray dynamics. The droplet and velocity size distributions are practical tools for the analysis of sprays cooling. The special benefit of the model is a Eulerian based which is less computationally intensive when compared to models that are based on the Lagrangian approach that tracks droplet parcel. The accuracy of using Lagrangian approach in polydispersed phase is always accurately less than Eulerian approach because it depends on the number of parcels while in Eulerian approach it depends on the proposed continuous distribution function. The main intent of the current work is to evaluate the capability of using the model for the initial predictions of the droplet size and velocity distribution for liquid nitrogen spray of solid-cone pressure swirl nozzle. The use of liquid injection pressure cases of up to 0.6MPa and spray cone angles of just 30◦ from three different sets of experimental data. The results being characterized are spray drop size distribution, liquid volume fraction and spray cone angle values. The unsteady analyses of the effect of injection pressure are studied on the cryogenic liquid nitrogen. The numerical results show that the maximum entropy method applies to liquid cryogenic spray and indicates that the model reacts correctly to changes in different injection pressures. Comparisons are also made with measured drop size distribution data that are reasonably captured and the spray cone angle is found to be in good agreement during initial and far-field spray angles.

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Jang, Sung Hwan, Sung Han Park, Jeong Whan Han, Chang Hee Lee, and Hyung Jun Kim. "Factors of Nozzle Design Affecting on Supersonic Flow in Cold Spray Process." Materials Science Forum 510-511 (March 2006): 1046–49. http://dx.doi.org/10.4028/www.scientific.net/msf.510-511.1046.

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The cold spray process is a relatively new process using high velocity metallic particles for surface modifications. Metallic powder particles which are injected into a converging-diverging nozzle are accelerated to supersonic velocities. In this study effects of nozzle design such as diameter of nozzle throat and length of converging and diverging part of the nozzle on gas and particle velocities developed after the nozzle exit are investigated.

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Gulizia, Stefan, A. Trentin, S. Vezzù, Silvano Rech, Peter King, Mahnaz Z. Jahedi, and Mario Guagliano. "Characterisation of Cold Spray Titanium Coatings." Materials Science Forum 654-656 (June 2010): 898–901. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.898.

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Cold spray is a solid state spray deposition process utilizing a supersonic De Laval nozzle to accelerate fine particles to high velocities. Particles plastically deform on impact to the substrate and to each other to create dense well adhered structures. In this study, the microstructure and mechanical properties of cold spray Titanium coatings deposited using nitrogen gas at different gas temperature and pressure were examined. In general, it was found that gas-atomised CP-titanium powder is capable of producing dense coating structures on aluminium alloy (Al6061) substrates. The micro-hardness, oxygen and nitrogen content of the coatings were found to be slightly higher than powder in the as-received condition. It was also found the coating residual stress was purely compressive when cold spray is conducted at high gas pressure and temperature.

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Koh, Jae Seok, Jae Chun Lee, Soon Haing Cho, and Seung Chul Choi. "Ultrasonic Spray Nozzle System with Piezoelectric Ceramics for Water Treatment Applications." Key Engineering Materials 317-318 (August 2006): 861–64. http://dx.doi.org/10.4028/www.scientific.net/kem.317-318.861.

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A new type of ultrasonic spray nozzle was fabricated employing PZT and Pb-free piezoelectric device. The spray nozzle was designed to disperse chemicals in a water treatment mixing tank. The piezoelectrics were packaged in an aluminum case with silicone resin for the aqueous solution proof packaging. Chemicals were dispersed with high efficiency, and the ultrasonic fine particle spraying was able to reduce the chemicals consumption. The removal efficiencies of heterotrophic bacteria and Escherichia coli by chemicals injected using designed ultrasonic spray nozzle were higher than the conventional methods.

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Sakaki, Kazuhiko. "Cold Spray Process ~ Overview and Application Trends ~." Materials Science Forum 449-452 (March 2004): 1305–8. http://dx.doi.org/10.4028/www.scientific.net/msf.449-452.1305.

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In Cold Spray method, a coating is formed by exposing a substrate to high velocity solid-phase particles, which have been accelerated by supersonic gas flow at a temperature much lower than the melting or softening temperature of the feedstock. Therefore, the nozzle geometry is important with regard to the cold spray method. This Cold Spray process is an exciting new spray technology that has the potential to overcome limitations of more traditional thermal spray processes for some important commercial applications. With this emerging technology, it is possible for the first time to rapidly deposit thin or very thick layers (mm to cm+) of a wide range of metals, and even some composite materials, without melting or vaporization, at or near room temperature, in an ambient air environment. Some potential areas of interest include: corrosion protection, wear reduction, highly conductive coatings (electrical or thermal), metal/glass or metal/ceramic joints (with less residual stress), ceramic/metal or graded metal/metal composites, thick deposits (mm to several cm range), reclamation of worn or mis-machined parts, metallization of glass or ceramics. The applications of Cold Spray can be examined in the field of an automobile and a rocket engine.

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Wang, Qiang, and Ming Xing Zhang. "Review on Recent Research and Development of Cold Spray Technologies." Key Engineering Materials 533 (December 2012): 1–52. http://dx.doi.org/10.4028/www.scientific.net/kem.533.1.

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Cold spray (CS) is an emerging revolutionary technology for deposition of metal or composite powders at a low temperature. High quality deposits can be produced without heating related defects, such as oxidation, phase transformation and residual tensile stress due to the shrinkage during fast cooling. The present contribution demonstrates the state of the art of CS process. Since nozzle is a key component in the CS equipment to prompt the efficiency of particle acceleration, the progress of its design is summarized. Major issues regarding to the successful adhesion of particles and corresponding interaction with substrates and existing deposits are discussed, in terms of numerical simulation and experimental observation. Current implemented CS applications are presented, and potential industrial applications are discussed. Keywords: cold spray; coatings; rapid manufacturing; particle impact; bonding mechanism; nozzle design

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Tsunoda, Akira, Yoshihito Otsuka, Akihiro Toguchi, Kumiko Watanabe, Ryou Nishino, and Tomoko Takahashi. "Survey on bacterial contamination of bidet toilets and relation to the interval of scrubbing these units." Journal of Water and Health 17, no. 6 (November 15, 2019): 863–69. http://dx.doi.org/10.2166/wh.2019.234.

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Abstract We conducted a survey to investigate the distribution of bacteria recovered from the bidet toilets at a district hospital. The nozzle surface and spray water of 192 bidet toilets were sampled for contamination. Of the 192 toilets sampled, the nozzle surface of 167 (87%) and the spray water of 181 (94%) were found to be contaminated by one or more of the following organisms: Enterobacteriaceae, Enterococcus spp., Staphylococcus spp., non-glucose-fermenting rods, other Gram-negative bacteria, other Gram-positive bacteria, and Candida spp. An extended spectrum of β-lactamase producing Escherichia coli was found in one nozzle surface and one spray water. The frequency of colonization with 104 or more recovered from the nozzle surface was significantly greater in the toilets scrubbed every week than that in the units scrubbed every day, but that from the spray water was not significantly different between the groups. The nozzle surface and the spray water in the bidet toilets were contaminated with a wide range of bacteria. Because the interval of scrubbing the toilets did not have an influence on the contamination of the spray water, self-cleaning mechanisms of spray water should be developed to prevent patients' possible infections.

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AKASHI, Takuma, Kazuhiko SAKAKI, and Masatoshi ITO. "S044023 Influence of cross sectional shape of cold spray nozzle on spray pattern." Proceedings of Mechanical Engineering Congress, Japan 2012 (2012): _S044023–1—_S044023–4. http://dx.doi.org/10.1299/jsmemecj.2012._s044023-1.

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Jafari, Soheil, Seyed Miran Fashandi, and Theoklis Nikolaidis. "Modeling and Control of the Starter Motor and Start-Up Phase for Gas Turbines." Electronics 8, no. 3 (March 25, 2019): 363. http://dx.doi.org/10.3390/electronics8030363.

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Improving the performance of industrial gas turbines has always been at the focus of attention of researchers and manufacturers. Nowadays, the operating environment of gas turbines has been transformed significantly respect to the very fast growth of renewable electricity generation where gas turbines should provide a safe, reliable, fast, and flexible transient operation to support their renewable partners. So, having a reliable tools to predict the transient behavior of the gas turbine is becoming more and more important. Regarding the response time and flexibility, improving the turbine performance during the start-up phase is an important issue that should be taken into account by the turbine manufacturers. To analyze the turbine performance during the start-up phase and to implement novel ideas so as to improve its performance, modeling, and simulation of an industrial gas turbine during cold start-up phase is investigated this article using an integrated modular approach. During this phase, a complex mechatronic system comprised of an asynchronous AC motor (electric starter), static frequency converter drive, and gas turbine exists. The start-up phase happens in this manner: first, the clutch transfers the torque generated by the electric starter to the gas turbine so that the turbine reaches a specific speed (cranking stage). Next, the turbine spends some time at this speed (purging stage), after which the turbine speed decreases, sparking stage begins, and the turbine enters the warm start-up phase. It is, however, possible that the start-up process fails at an intermediate stage. Such unsuccessful start-ups can be caused by turbine vibrations, the increase in the gradients of exhaust gases, or issues with fuel spray nozzles. If, for any reason, the turbine cannot reach the self-sustained speed and the speed falls below a certain threshold, the clutch engages once again with the turbine shaft and the start-up process is repeated. Consequently, when modeling the start-up phase, we face discontinuities in performance and a system with variable structure owing to the existence of clutch. Modeling the start-up phase, which happens to exist in many different fields including electric and mechanical application, brings about problems in numerical solutions (such as algebraic loop). Accordingly, this study attempts to benefit from the bond graph approach (as a powerful physical modeling approach) to model such a mechatronic system. The results confirm the effectiveness of the proposed approach in detailed performance prediction of the gas turbine in start-up phase.

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Cojocaru, Cristian V., Maniya Aghasibeig, and Eric Irissou. "NiCoCrAlX (X = Y, Hf and Si) Bond Coats by Cold Spray for High Temperature Applications." Journal of Thermal Spray Technology 31, no. 1-2 (January 2022): 176–85. http://dx.doi.org/10.1007/s11666-022-01322-2.

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AbstractMCrAlX powder compositions (M = Ni,Co and X = Y, Hf, Si or combination) are often thermally sprayed via vacuum plasma spray (VPS), low pressure plasma spray (LPPS) or high velocity oxy-fuel to produce high temperature oxidation and hot corrosion resistant bond coats for thermal barrier coatings (TBCs). Cold spray technology is currently considered as a promising alternative to the traditional thermal spray solutions, having the advantage of delivering oxide-free and very dense metallic coatings at relatively lower costs compared to VPS and LPPS. NiCoCrAlY and NiCoCrAlYHfSi bond coats were deposited using a high pressure cold spray system and the influence of feedstock properties on the deposited bond coats were investigated. To improve NiCoCrAlYHfSi bond coat deposition, laser assisted cold spray (LACS) was employed. The results show that LACS can be successfully used to deposit this particular powder while eliminating nozzle erosion and low deposition efficiency disadvantages observed with conventional cold spray. To identify the optimal LACS setup for deposition of dense and uniform coatings, different laser/spray jet configurations were examined. TBCs with bond coats sprayed at the optimal configuration were assessed isothermally at 1150 °C in air for up to 500 h, and the results showed formation of a thermally grown oxide layer composed of predominantly Al2O3 with embedded small clusters of Hf-Y-rich oxides.

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TOMORI, Ryoji, Hiroshi KATANODA, and Minoru FUKUHARA. "G050061 Numerical Simulation of Compressive Flow in Cold Spray Nozzle." Proceedings of Mechanical Engineering Congress, Japan 2012 (2012): _G050061–1—_G050061–4. http://dx.doi.org/10.1299/jsmemecj.2012._g050061-1.

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YANAGITA, Yuki, Hiroshi KATANODA, and Minoru FUKUHARA. "G050062 Experimental Study on Supersonic Flow in Cold Spray Nozzle." Proceedings of Mechanical Engineering Congress, Japan 2012 (2012): _G050062–1—_G050062–4. http://dx.doi.org/10.1299/jsmemecj.2012._g050062-1.

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Sharma, Mala M., Francis L. Wolff, Timothy J. Eden, and Victor K. Champagne. "Prediction of the Flattening Ratio and Hardness of Cold Sprayed Deposits." Solid State Phenomena 338 (October 28, 2022): 3–15. http://dx.doi.org/10.4028/p-3f4541.

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Cold spray technology is a solid-state deposition process where solid particles are accelerated to very high velocities by expanding a compressed gas through a supersonic nozzle. The particles impact a substrate located approximately 25 mm from the exit plane of the nozzle. Predicting the deformation and resultant properties helps in developing process parameters and tailoring coatings to get the desired properties. In this study, aluminum, copper, and nickel coatings were produced using a range of process parameters that produced different particle impact velocities. The Hollomon power law relationship and Johnson-Cook flow stress model were utilized to predict the hardness of cold spray coatings. Results showed there was good agreement between the predicted and measured hardness of the respective coatings. Additionally, a methodology was developed to measure deformation in the form of a flattening ratio of the deposited particles. There was good agreement between the predicted and measured flattening ratio, especially for the Al and Ni feedstock powders.

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Шорінов, Олександр Володимирович, Андрій Олегович Волков, Сергій Євгенійович Маркович, and Анатолій Іванович Долматов. "РОЗРАХУНОК ТЕМПЕРАТУРНО-ШВИДКІСНИХ ПАРАМЕТРІВ ЧАСТИНОК ПРИ ХОЛОДНОМУ ГАЗОДИНАМІЧНОМУ НАПИЛЮВАННІ." Aerospace technic and technology, no. 7 (August 31, 2019): 139–44. http://dx.doi.org/10.32620/aktt.2019.7.20.

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The method of computational fluid dynamics (CFD) for the supersonic nozzle SK-20 of the low-pressure cold gas-dynamic spraying equipment DYMET-405 was applied for calculation of particles impact temperature and velocity. The application of the CFD method is the one-dimensional isentropic gas-dynamic model considers the flow only along the nozzle axis, without taking into account the heat exchange with the nozzle and the friction losses on the internal walls, which leads to obtaining overestimated results of calculations. Previously it was found out that the difference in the values obtained by numerical simulation and the results of calculations of a one-dimensional isentropic model was less than 10%. Numerical simulation of the two-phase flow of the cold spray process has been performed using the Ansys Fluent Academic software package. The influence of the initial cold spray process parameters such as temperature and pressure at the nozzle inlet on the change in temperature and velocity of aluminum particles with a diameter of 25 μm at the moment of impact with the substrate has been studied. Also, the influence of the particle size on the above-mentioned parameters has been obtained. The numerical simulation results of the particle impact temperature with the substrate have been used to calculate the critical velocity of aluminum powder – the velocity needed for coating formation. It is known that the formation of cold spray coatings depends on the velocity of the powder particles. For each material, there is a critical velocity at which the process of forming the coating begins. At particle velocities above the critical one, their adhesion to the substrate and the formation of the coating, due to the plastic deformation of the particles, occurs, while at lower velocities the surface erosion or deposition with low efficiency under certain conditions is observed. As a result of simulation and calculations of the critical velocity, the window of spraying was developed, that is the region of values of velocities and temperatures of the particles of aluminum powder, depending on the temperature and pressure of the air at the nozzle inlet, at which the formation of coatings is possible.

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Park, Sung Han, Jeong Whan Han, Chang Hee Lee, and Hyung Jun Kim. "Effect of Curvature on Gas-Particle Flow in Converging and Diverging Supersonic Nozzle." Solid State Phenomena 124-126 (June 2007): 1697–700. http://dx.doi.org/10.4028/www.scientific.net/ssp.124-126.1697.

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A cold spray process is a relatively new process using high velocity metallic particles for surface modifications. Metallic powder particles which are injected into a converging-diverging nozzle are accelerated to supersonic velocities. In this study a comparative study was performed to figure out the effect of curvature on gas and particle flow in converging-diverging nozzle. And, the critical radius of curvature in converging and diverging section of nozzle and the behavior of the gas and particle flow were determined and calculated, respectively.

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Tian, Jiameng, Bin Chen, Zhifu Zhou, and Dong Li. "Theoretical Study on Cryogen Spray Cooling in Laser Treatment of Ota’s Nevus: Comparison and Optimization of R134a, R404A and R32." Energies 13, no. 21 (October 28, 2020): 5647. http://dx.doi.org/10.3390/en13215647.

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Cryogen spray cooling (CSC) could be applied clinically for the laser therapy of Ota’s nevus, a dermal hyperplastic pigmented disease with a morbidity rate of 0.1–0.6% in the Asian population. An accurate, efficient, complete simulation system that considers the entire spray cooling process, including cryogen flow in the tube nozzle, spray dynamics and internal phase change heat transfer (cold injury) in skin tissue, was established to determine suitable cryogen and cooling parameters. The optimum spray distances for R134a, R404A and R32 were determined to be 66.0, 43.1 and 22.5 mm, respectively. The corresponding maximum surface heat fluxes were 363.5, 459.9, and 603.6 kW∙m−2, respectively. The maximum surface heat flux of R32 with small spray distance was 1.66 times as large as that of R134a, indicating the potentially good cooling performance and precise targeted cooling of R32 during the laser therapy of Ota’s nevus. The cooling durations that caused cold injury of skin tissue were 2.3, 1.4, and 1.1 s for R134a, R404A, and R32, respectively. The interval between CSC and laser irradiation was optimized to 90–162 ms for R134a, R404A and R32, in consideration of the cooling effect, depth, uniformity, and risk of cold injury.

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Wong, Wilson, Ahmad Rezaeian, Eric Irissou, Jean Gabriel Legoux, and Steve Yue. "Cold Spray Characteristics of Commercially Pure Ti and Ti-6Al-4V." Advanced Materials Research 89-91 (January 2010): 639–44. http://dx.doi.org/10.4028/www.scientific.net/amr.89-91.639.

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Ti and Ti-6Al-4V coatings were deposited by cold gas dynamic spray process using nitrogen as propellant gas. For Ti, the inlet gas temperature and pressure were varied for two different powder morphologies in such a way that the average particle velocity ranged from ~600 to 850 m/s. In addition, the nozzle traverse speed was varied. For all conditions, the deposition efficiency, the porosity, and the microhardness were measured. It is shown that the porosity level decreased as the gas temperature and pressure increased, whereas the velocity, deposition efficiency, and microhardness increased. Furthermore, it is observed that a lower nozzle traverse speed engendered a softer coating. The coating adhesion on a grit 24 Al2O3 blasted mild steel surface was established to be greater than 78.8 MPa. In addition, a Ti-6Al-4V coating was produced and was determined to be slightly more porous compared to a CP Ti coating.

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AKASHI, Takuma, and Kazuhiko SAKAKI. "525 Influence of Width of Rectangular Cold Spray Nozzle on Gas Flow and Spray Pattern." Proceedings of the Materials and processing conference 2013.21 (2013): _525–1_—_525–4_. http://dx.doi.org/10.1299/jsmemp.2013.21._525-1_.

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Forero-Sossa, Paola Andrea, Astrid Lorena Giraldo-Betancur, Carlos A. Poblano-Salas, Aixa Ibeth Gutierrez-Pérez, Esaú Moises Rodríguez-Vigueras, Jorge Corona-Castuera, and John Henao. "Nozzle Geometry and Particle Size Influence on the Behavior of Low Pressure Cold Sprayed Hydroxyapatite Particles." Coatings 12, no. 12 (November 29, 2022): 1845. http://dx.doi.org/10.3390/coatings12121845.

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Low-pressure cold spray (LPCS) technology has attracted interest for the deposition of ceramic coatings due to the thermo-kinetic conditions experienced by the sprayed particles. Unlike conventional thermal spray techniques, the spraying conditions in LPCS can be controlled to avoid the formation of undesired phases. However, ceramics deposition through this process is still challenging. The present study includes a finite element analysis and simulation study of the kinetic conditions of ceramic particles in the LPCS process based on experimental data. The analysis seeks to discuss the effect of nozzle geometry on the kinetic and thermal energy of the sprayed particles at impact and elucidate how the particle travels within the high-velocity jet to be deposited onto a metallic surface. This work examines the behavior of hydroxyapatite particles as a function of particle size and nozzle geometry during LPCS deposition. Interestingly, the results from this research suggest that particle size and nozzle geometry have an influence on the deposition of hydroxyapatite particles. Inertia of large particles proved to be beneficial in keeping their trajectories, allowing them to contribute to the formation of the coatings. Nozzle geometry modifications produced changes in the jet profile and affected the homogeneity of the coatings obtained. This finding contributes to a better understanding of the deposition of hydroxyapatite particles by cold spraying.

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Widener, Christian A., Marius Ellingsen, and Michael Carter. "Understanding Cold Spray for Enhanced Manufacturing Sustainability." Materials Science Forum 941 (December 2018): 1867–73. http://dx.doi.org/10.4028/www.scientific.net/msf.941.1867.

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High pressure cold spray has been showing increasing promise and application for structural repairs and coating applications where wrought like strengths are required. For example, numerous applications have been developed for repairing high cost and long lead time parts for the aerospace and defense market, such as aircraft skin panels, titanium hydraulic lines, aluminum valve actuator internal bores, hardened and chromed steel shafts, gas turbine engine parts, magnesium castings, and many more. These processes also have direct application in commercial markets like transportation and heavy industry. In particular, parts with lead times in excess of 12 months have been successfully repaired and re-introduced into service. This saves not only the direct cost of the part, but also returns the system to service much sooner. Additional benefits of field application with a hand-held nozzle assembly are also possible, particularly for power plants, refineries, and other large industrial plant operations. Cold spray consequently has a tremendous opportunity to enhance manufacturing sustainability by repairing parts that previously could only be replaced and recycled. It is environmentally friendly, as there are no toxic fumes or other harmful emissions from cold spray. Furthermore, because parts are being repaired and refurbished rather than replaced, there is tremendous cost, energy, and overall environmental benefit, making cold spray a “green” technology and an excellent technology for enhancing the long-term sustainability of high value assets.

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MacDonald, D., S. Leblanc-Robert, R. Fernández, A. Farjam, and B. Jodoin. "Effect of Nozzle Material on Downstream Lateral Injection Cold Spray Performance." Journal of Thermal Spray Technology 25, no. 6 (June 9, 2016): 1149–57. http://dx.doi.org/10.1007/s11666-016-0426-4.

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Qiao, Hai Jun, and Jia Nan Wu. "Discussions of Influence of some Factors on New Vehicle Absorption Cold Source." Applied Mechanics and Materials 532 (February 2014): 479–82. http://dx.doi.org/10.4028/www.scientific.net/amm.532.479.

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Small absorption cold source for car air conditioners differs from the compression cold source characteristics of the cold source, such as vehicle shaking can cause problems such as pollution of coolant water. Based on computational fluid dynamics (CFD) method, spray process in a new small cold source of lithium bromide absorption chiller was simulated by using the k-epsilon model and volume of fraction (VOF) model, which can capture the free surface of the two phase of liquid and gas, and the effects of nozzle profile and car bumping are analyzed, providing a theoretical basis for the application of a small absorption cold source for automotive.

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He, Xin, Yaqing Chen, Yilong Ma, Dengfeng Hu, and Haoran Gao. "Hybrid Numerical Simulation of Jet Blast Distance of a Departing Aircraft." Mathematical Problems in Engineering 2021 (March 30, 2021): 1–11. http://dx.doi.org/10.1155/2021/5597414.

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A hybrid numerical simulation method was established by combining the Spalart-Allmaras (SA) turbulence model and detached eddy simulation (DES). Numerical simulations were carried out to model cold and hot spray conditions of a nozzle without considering the internal flow of an engine to determine jet conditions. Analysis results show that the calculated hot spray results more in line with the reality. The jet effect of a typical aircraft engine was simulated numerically to determine the distance influenced by the jet blast from a departing aircraft engine.

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Zhao, Le, Yu Zhang, Yuanjiang Pei, Anqi Zhang, and Muhsin M. Ameen. "CFD-Guided Evaluation of Spark-Assisted Gasoline Compression Ignition for Cold Idle Operation." Sustainability 13, no. 23 (November 26, 2021): 13096. http://dx.doi.org/10.3390/su132313096.

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A closed-cycle, three-dimensional (3D) computational fluid dynamics (CFD) analysis campaign was conducted to evaluate the performance of using spark plugs to assist gasoline compression ignition (GCI) combustion during cold idle operations. A conventional spark plug using single-sided J-strap design was put at a location on the cylinder head to facilitate spray-guided spark assistance. Ignition was modeled with an L-type energy distribution to depict the breakdown and the arc-to-glow phases during the energy discharge process. Several key design parameters were investigated, including injector clocking, number of nozzle holes, spray inclusion angle, number of fuel injections, fuel split ratio, and fuel injection timings. The study emphasized the region around the spark gap, focusing on flame kernel formation and development and local equivalence ratio distribution. Flame kernel development and the ignition process were found to correlate strongly with the fuel stratification and the flow velocity near the spark gap. The analysis results showed that the flame kernel development followed the direction of the local flow field. In addition, the local fuel stratification notably influenced early-stage flame kernel development due to varying injection spray patterns and the fuel injection strategies. Among these design parameters, the number of nozzle holes and fuel injection timing had the most significant effects on the engine combustion performance.

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Brusentseva, Tatyana A., Vladislav S. Shikalov, Sergei M. Lavruk, and Vasily M. Fomin. "Simulation of Thermoplastic Powder Cold Spraying." Journal of Siberian Federal University. Mathematics & Physics 14, no. 6 (December 2021): 726–34. http://dx.doi.org/10.17516/1997-1397-2021-14-6-726-734.

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The work is devoted to the deposition of composite powder materials by cold spray method. As a spraying material, a thermoplastic compound «WAY» for marking the roadway was used. An asphalt concrete was used as a substrate. As a result of experimental studies, the dependence of the deposition efficiency on the stagnation temperature of the working air in the ejector nozzle was obtained. The ANSYS Fluent package was used for evaluative modeling of the cold spraying process. Gas flow patterns were obtained in the computational domain without particles and taking into account the interaction of the flow with particles. The trajectory of the particles was calculated for various spraying parameters

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Silva, Fernando Santos da, Núria Cinca, Sergi Dosta, Irene Garcia Cano, Josep Maria Guilemany, and Assis Vicente Benedetti. "Cold gas spray coatings: basic principles corrosion protection and applications." Eclética Química Journal 42, no. 1 (December 30, 2017): 09. http://dx.doi.org/10.26850/1678-4618eqj.v42.1.2017.p09-32.

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In this review, the beginnings and evolution of the cold gas spray (CGS) technique are described, followed by the main fundamental aspects of the technique together with a description of the several spraying systems up to date. Sequentially, the main spray parameters and their influence on the properties of the coatings are reported. Afterwards, the most important methodologies for preparing the feedstock powders to be sprayed, the effect of the powder composition, microstructure, particle size and shape on the properties of the coatings are discussed. The nature of the spray gun and nozzle, and the substrate pre-treatments were also discussed. With regard to microstructure and properties, the chemical and physical characterization of the coatings and the performance in protecting the substrates against corrosion together with some mechanical properties are presented and compared. The lacking systematic studies about the great part of investigated systems is the main drawback to compare the published results. Closing this review, the main applications, and the potentialities of the CGS coatings are evidenced.

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Alonso, L., M. A. Garrido, and P. Poza. "An optimisation method for the cold-spray process: On the nozzle geometry." Materials & Design 214 (February 2022): 110387. http://dx.doi.org/10.1016/j.matdes.2022.110387.

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KAMITAKAMAKI, Ryota, Hiroshi KATANODA, and Minoru FUKUHARA. "G050044 Numerical simulation on the influence of nozzle shape in cold spray." Proceedings of Mechanical Engineering Congress, Japan 2011 (2011): _G050044–1—_G050044–4. http://dx.doi.org/10.1299/jsmemecj.2011._g050044-1.

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Journal articles on the topic 'Cold spray nozzles'

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