Abstract
Many studies on critical nozzles have been made to accurately measure the mass flow rate of gas and standardize its performance as a flow meter. Recently, much interest has been given to measuring very small mass flow rates in industrial fields, such as MEMS applications. However, the design and performance data of the critical nozzles obtained thus far have been applied mainly to critical nozzles with comparatively large diameters, and available studies on miniature critical nozzles are lacking. In this study, computational fluid dynamics (CFD) method was applied to investigate the influence of the diffuser angle on the discharge coefficient of miniature critical nozzles. In computations, the throat diameter of a critical nozzle varied from 0.2 to 5.0 mm, and the diffuser angle changed from 2° to 8°. The computational results were validated with some available experimental data. The present computational results accurately predicted the discharge coefficient of gas flows through miniature critical nozzles. The discharge coefficient is considerably influenced by the diffuser angle as the throat diameter of the nozzle becomes smaller below a certain value. This implies that miniature critical nozzles should be designed with careful consideration of its effects.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
S. P. Tang and J. B. Fenn, Experimental Determination of the Discharge Coefficients for Critical Flow through an Axisymmetric Nozzle, AIAA Journal, 16(1) (1978) 41–46.
H. D. Kim, J. H. Kim and K. A. Park, Setoguchi, T., and Matsuo, S., Computational Study of the Gas Flow through a Critical Nozzle, IMechE Journal of Mechanical Engineering Science, 217 (2003)1179–1189.
B. T. Arnberg, C. L. Britton and W. F. Seidel, Discharge Coefficient Correlations for Circular Arc Venturi Flow Meters at Critical (Sonic) Flow, Journal of Fluids Engineering, (1974) 111–123.
H. D. Kim, J. H. Kim and K. A. Park, Study for the Gas Flow through a Critical Nozzle, Proceedings of ASME FEDSM’03 4 th ASME_JSME Joints Fluids Engineering Conference, Hawaii (2003) FEDSM2003-45593.
J. H. Kim, H. D. Kim and K. A. Park, Computational/Experimental Study of a Variable Critical Nozzle Flow, Flow Measurement and Instrumentation, 17(2) (2006) 81–86.
N. Bignell, The Use of Small Sonic Nozzles at Low Reynolds Numbers, Flow Measurement and Instrumentation, 7 (1996) 77–83.
Y. M. Choi, K. A. Park, J. T. Park, H. M. Choi and S. O. Park, Interference Effects of Three Sonic Nozzles of Different Throat Diameters in the Same Meter Tube, Flow Measurement and Instrumentation, 10 (1999) 175–181.
H. D. Kim, J. H. Kim, K. A. Park, T. Setoguchi and S. Matsuo, Study of the Effects of Unsteady Downstream Conditions on the Gas Flow through a Critical Nozzle, IMechE Journal of Mechanical Engineering Science, 218 (2004) 1163–1173.
J. H. Kim, H. D. Kim, K. A. Park, T. Setoguchi and S. Matsuo, A Fundamental Study of a Variable Critical Nozzle Flow, Experiments in Fluids, 40(1) (2006) 127–134.
J. Mueller, W. C. Tang, A. P. Wallace, W. J. Li, D. P. Bame, I. Chakraborty and R. A. Lawton, Design, analysis and fabrication of a Vaporizing Liquid Micro-Thruster, Proceeding of 33 rd AIAA Joint Propulsion Conf., (1997) 1–10.
A. R. Choudhuri, B. Baird, S. R. Gollahalli and S. J. Schneider, Effects of Geometry and Ambient Pressure on Micro-nozzle Flow, 37th AIAA/ASME/SAE/ASEE Joint Propulsion conference and Exhibit, (2003) AIAA Paper 2003-0672.
S. Nakao, T. Irayama and M. Takamoto, Relations between the discharge coefficients of the sonic venture nozzle and a kind of gas, JSME Journal of Mechanical Engineering B, 66 (2000) 438–444.
K. A. Park, Y. M. Choi, H. M. Choi, T. S. Cha and B. H. Yoon, Evaluation of Critical Pressure Ratio of Sonic Nozzles at Low Reynolds Numbers, Flow Measurement and Instrumentation, The 12(1) (2001) 37–41.
Author information
Authors and Affiliations
Corresponding author
Additional information
This paper was recommended for publication in revised form by Associate Editor Do Hyung Lee
Heuy-Dong Kim received his BS and MS degrees in Mechanical Engineering from the Kyungpook National University, Korea, in 1986 and 1988, respectively. He then received his PhD degree from the Kyushu University, Japan, in 1991. Dr. Kim is currently a Professor at the School of Mechanical Engineering, Andong National University, Korea. His research interests include high-speed trains, ramjet and scramjet, shock tube and technology, shock wave dynamics, explosions and blast waves, flow measurement, aerodynamic noises, and supersonic wind tunnels.
Jae-Hyung Kim received his BS and MS degrees in Mechanical Engineering from the Andong National University, Korea, in 2002 and 2004, respectively. He is currently a PhD student in the Department of Aerospace Engineering at the Graduate School of Nagoya University, Japan. His research interests include flow measurement, compressible internal flows, shock waves, and aerodynamics control.
Rights and permissions
About this article
Cite this article
Kim, JH., Kim, HD. Effect of diffuser angle on the discharge coefficient of miniature critical nozzles. J Mech Sci Technol 24, 1793–1798 (2010). https://doi.org/10.1007/s12206-010-0627-6
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12206-010-0627-6