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Determination of Supercavity Shape for Axisymmetric Cavitators at Different Non-Zero Attack Angles, Using Boundary Element Method

Published online by Cambridge University Press:  08 May 2012

R. Shafaghat,
S. M. Hosseinalipour and
A. Vahedgermi
R. Shafaghat*
Affiliation:
Department of Mechanical Engineering NIT, Iran
S. M. Hosseinalipour
Affiliation:
Department of Mechanical Engineering IUST, Iran
A. Vahedgermi
Affiliation:
Department of Mechanical Engineering IUST, Iran
*
*Corresponding author (rshafaghat@nit.ac.ir)

Abstract

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When fluid passes a cavitator in the supercavitating flow, a supercavity forms behind the cavitator. Variation of the cavitator attack angle can influence theshape of the formed supercavity behind the cavitator. Consequently, it will affect the stability of supercavity behind the supercavitating cavitator with after body. In this study, a direct boundary element method (DBEM) is being formulated and numerically solved for3D unbounded potential flowspassing supercavitating bodies of revolution at different attack angles. In the analysis of potential flows passing supercavitating bodies at non-zero attack angles, a cavity closure model must be employed in order to close the mathematical formulationand guarantee the solution uniqueness. In the present study, we employ modified Riabouchinsky closure model. Since the location of the cavity surface is unknown at prior, an iterative scheme is used and for the first stage, an arbitrary cavity surface is assumed. The flow field is then solved and by an iterative process, the location of the cavity surface is corrected. Upon convergence, the exact boundary conditions are satisfied on the body-cavity boundary. A powerful CFD codeis developed to solve the 3D supercavitating flows behind all types of axisymmetric cavitators (such as disk, cone, etc) at zero and non-zero attack angles. The predictions of the CFD code are compared with those generated by verified existing data. The predictions of the code for supercavitating cones and disks seem to be excellent. Using the obtained data from CFD code, we investigate the supercavity shapesand corresponding stability at different attack angles with a fixed cavitation number.

Keywords

Boundary element methodSupercavitating flowsCavitatorCavity closureCavitation number3DAttack angle

Information

Type
Articles
Information
Journal of Mechanics , Volume 28 , Issue 2 , June 2012, pp. 383 - 389
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2012

References

REFERENCES

1. Kuklinski, R., Henoch, C. and Castano, J., “Experimental Study of Ventilated Cavities on Dynamic Test Model,” Naval Undersea Warfare Center., Cav2001: Session B3.004 (2001).Google Scholar
2. Reichardt, H., “The Physical Laws Governing the Cavitation Bubbles Produced Behind Solids of Revolution in a Fluid Flow,” The Kaiser Wilhelm Institute for Hydrodynamic Research., Gottingen, Rep. UM 6628, (1945).Google Scholar
3. Garabedian, P. R., “The Calculation of Axially Symmetric Cavities and Jets,” Pacific Journal of Mathematics, 6, pp. 611–689 (1956).Google Scholar
4. Cuthbert, J. and Street, R., “An Approximate Theory for Supercavitating Flow About Slender Bodies of Revolution,” LMSC Report TM81-73/39, Lockheed Missiles and Space Co., Sunnyvale, California, (1964).Google Scholar
5. Brennen, C. A., “Numerical Solution of Axisymmetric Cavity Flows,” Journal of Fluid Mechanics, 37, p. 4, 671–688 (1969).CrossRefGoogle Scholar
6. Chou, Y. S., “Axisymmetric Cavity Flows Past Slender Bodies of Revolution,” Journal of Hydronautics, 8, pp. 13–18 (1974).CrossRefGoogle Scholar
7. Aitchison, J. M., “The Numerical Solution of Planar and Axisymmetric Cavitational Flow Problems,” Computers and Fluids, 12, pp. 55–65 (1984).CrossRefGoogle Scholar
8. Hase, P. M., “InteriorSource Methods for Planar and Axisymmetric Supercavitating Flows,” Thesis Submitted for the Degree of Doctor of Philosophy, (2003).Google Scholar
9. Verghese, A. N., Uhlman, J. S. and Kirschner, I. N., “Numerical Analysis of High – Speed Bodies in Partially Cavitation Axisymmetric Flow, Transactions of ASME,” Journal of Engineering, 127, pp. 41–54 (2005).Google Scholar
10. Ingber, M. S. and Halley, C. E., “Numerical Modelling of Cavities on Axisymmetric Bodies at Zero and Non-Zero Angle of Attack,” International Journal of Numerical Method in Fluid, 15, pp. 251–271 (1992).CrossRefGoogle Scholar
11. Wrobel, L. C., “A Simple and Efficient BEM Algorithm for Planar Cavity Flows,” International Journal for Numerical Methods in Fluids, 14, pp. 524–537 (1992).CrossRefGoogle Scholar
12. Becker, A. A., The Boundary Element Method in Engineering, McGraw-Hill Book Company (1992).Google Scholar
13. Kennon, S. R., “Boundary Element Method,” Graduate Research Assistant, Department of Aerospace Engineering and Engineering Mechanics, University of Texas at Austin, Austin, TX. (1986).Google Scholar
14. Mukherjee, S. and Morjaria, M., “On the Efficiency and Accuracy of the Boundary Element Method,” International Journal for Numerical Methods in Engineering, 20, pp. 515–522 (1984).Google Scholar
15. Kirschner, I. N., Fine, N. E., Uhlman, J. S. and Kring, D. C., “Numerical Modeling of Supercavitating Flows,” Paper presented at the RTO AVT lecture series on “Supercavitating Flows”, held on the Von Karman Institute (VKI) in Belgium, and published in RTO EN-010, 12–16 (2001).Google Scholar
16. Kirschner, I. N., Uhlman, J. S., Varghese, A. N. and Kuria, I. M., “Supercavitating Projectiles in Axisymmetric Subsonic Liquid Flows,” Proceedings of the ASME & JSME Fluids Engineering Annual Conference & Exhibition, Cavitation and Multiphase Flow Forum, FED 210, Katz, J. and Matsumoto, Y., editors, Hilton Head Island, SC (1995).Google Scholar
17. Shafaghat, R., Hosseinalipour, S. M. and Shariatifard, A., “Numerical Analysis of a Two Dimensional Bounded Supercavitation Flow, 15th Annual Conferences of the CFD Society of Canada,” Toronto, Canada, May 27-31 (2007).Google Scholar
18. Shafaghat, R., Hosseinalipour, S. M. and Shariatifard, A., “Numerical Analysis of Two-Dimensional Supercavitation Flow Using a Boundary Element Method,” Journal of Numerical Simulations in Engineering, University of Mazandaran. 3, pp. 216–223 (2008).Google Scholar
19. Shafaghat, R., Hosseinalipour, S. M., Nouri, N. M. and Vahedgermi, A., “Mathematical Approach to Investigate the Behavior of the Principal Parameters in Axisymmetric Supercavitating Flows, Using Boundary Element Method,” Journal of Mechanics, 25, pp. 465–473 (2009).CrossRefGoogle Scholar
20. Shafaghat, R., Hosseinalipour, S. M. and Vahedgermi, A., “Numerical Analysis of Axisymmetric Supercavitating Flows,” Using Boundary Element Method, 11th Fluid Dynamics Conference, K. N. Toosi University of Technology (2008).Google Scholar