2차원 단순 물체의 초공동 유동에 대한 수치해석
Numerical Analysis of Supercavitating Flows of Two-Dimensional Simple Bodies
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In this paper, a numerical analysis is carried out to study the characteristics of supercavitating flows and the drag of relatively simple two-dimensional and axisymmetric bodies which can be used for supercavity generation device, cavitator, of a high-speed underwater vehicle. In order to investigate the suitability of numerical models, cavity flows around the hemispherical head form and two-dimensional wedge are calculated with combinations of three turbulence models(standard , realizable , Reynolds stress) and two cavitation models(Schnerr-Sauer, Zwart-Gerber–Belamri). From the results, it is confirmed that the calculated cavity flow is more affected by the turbulence model than the cavitation model. For the calculation of steady state cavity flows, the convergence in case of the realizable model is better than the other turbulence models. The numerical result of the Schnerr-Sauer cavitation model is changed less by turbulence model and more robust than the Zwart-Gerber–Belamri model. Thus the realizable turbulence model and the Schnerr-Sauer cavitation model are applied to calculate supercavitating flows around disks, two dimensional 10° and 30°wedges. In case of the disk, the cavitation number dependences of the cavity size and the drag coefficient predicted are similar to either experimental data or Reichardt’s semi-empirical equations, but the drag coefficient is overestimated about 3% higher than the Reichardt’s equation. In case of the wedges, the cavitation number dependences of the cavity size are similar to experimental data and Newman’s linear theory, and the agreement of the cavity length predicted and Newman’s linear theory becomes better as decreasing cavitation number. However, the drag coefficients of wedges agree more with experimental data than those of Newman’s analytic solution. The cavitation number dependences of the drag coefficients of both the disk and the wedge appear linear and simple formula for estimating the drag of supercavitating disks and wedges are suggested. Consequently, the CFD scheme of this study can be applied for numerical analysis of supercavitating flows of the cavitator and the cavitator design.
Abstract
In this paper, a numerical analysis is carried out to study the characteristics of supercavitating flows and the drag of relatively simple two-dimensional and axisymmetric bodies which can be used for supercavity generation device, cavitator, of a high-speed underwater vehicle. In order to investigate the suitability of numerical models, cavity flows around the hemispherical head form and two-dimensional wedge are calculated with combinations of three turbulence models(standard , realizable , Reynolds stress) and two cavitation models(Schnerr-Sauer, Zwart-Gerber–Belamri). From the results, it is confirmed that the calculated cavity flow is more affected by the turbulence model than the cavitation model. For the calculation of steady state cavity flows, the convergence in case of the realizable model is better than the other turbulence models. The numerical result of the Schnerr-Sauer cavitation model is changed less by turbulence model and more robust than the Zwart-Gerber–Belamri model. Thus the realizable turbulence model and the Schnerr-Sauer cavitation model are applied to calculate supercavitating flows around disks, two dimensional 10° and 30°wedges. In case of the disk, the cavitation number dependences of the cavity size and the drag coefficient predicted are similar to either experimental data or Reichardt’s semi-empirical equations, but the drag coefficient is overestimated about 3% higher than the Reichardt’s equation. In case of the wedges, the cavitation number dependences of the cavity size are similar to experimental data and Newman’s linear theory, and the agreement of the cavity length predicted and Newman’s linear theory becomes better as decreasing cavitation number. However, the drag coefficients of wedges agree more with experimental data than those of Newman’s analytic solution. The cavitation number dependences of the drag coefficients of both the disk and the wedge appear linear and simple formula for estimating the drag of supercavitating disks and wedges are suggested. Consequently, the CFD scheme of this study can be applied for numerical analysis of supercavitating flows of the cavitator and the cavitator design.
참고문헌 (26)
- 안병권, "Experimental and numerical studies on super-cavitating flow of axisymmetric cavitators", International Journal of Naval Architecture and Ocean Engineering, 2(1), pp.39~44 (2010), 대한조선학회
- 안병권, "Experimental investigation of supercavitating flows", International Journal of Naval Architecture and Ocean Engineering, 4(2), pp.123~131 (2012), 대한조선학회[DOI]
- Ahn, S. S., "An integrated aproach to the design of supercavitating underwater vehicles", 박사, pp.2007
- "User’s Guide" (2010), SAS IP Inc
- Alyanak, E., "Variable shape cavitator design for a supercavitating torpedo", Proceedings of 10th AIAA, 2004, ~
- Balas, G.J., "Control of High-Speed Underwater Vehicles. Control of Uncertain Systems", LNCIS, 329, pp.25~44 (2006)
- Wanil Byun, "Buckling analysis and optimal structural design of supercavitating vehicles using finite element technology", International Journal of Naval Architecture and Ocean Engineering, 3(4), pp.274~285 (2011), 대한조선학회
- 김형태, "고 레이놀즈수 유동의 수치해석시 벽함수 사용에 관한 연구", 대한조선학회 논문집, 47(5), pp.647~655 (2010), 대한조선학회
- Minho Chung, "Experimental study on dynamic buckling phenomena for supercavitating underwater vehicle", International Journal of Naval Architecture and Ocean Engineering, 4(3), pp.183~198 (2012), 대한조선학회
- Foot, J.P., "Investigation of Aluminium Particle Combustion for Underwater Propulsion Applications", AIAA, ASME, SAE, and ASEE, Joint Propulsion Conference and Exhibit (1996)
- Dong-Hyun Kim, "Numerical simulation of cavitating flow past axisymmetric body", International Journal of Naval Architecture and Ocean Engineering, 4(3), pp.256~266 (2012), 대한조선학회
- 김지혜, "3차원 축대칭 캐비테이터의 초월공동유동 수치해석", 대한조선학회 논문집, 50(3), pp.160~166 (2013), 대한조선학회
- Kim, S.H., "Controller Design for a Supercavitating Vehicle in Transition Phase", The Korean Association of Ocean Science and Technology Societies (2013)
- Kim, Y.G., "Propulsion technologies of supercavitating rocket torpedo", Proceedings of the Korean Society of Propulsion Engineers, Fall Conference, pp.383~387 (2011)
- Knapp, R.T., "Cavitation, In Iowa Institute of Hydraulic Research" (1970), Institute of Hydraulic Research
- Miller, T.F., "Green rocket propulsion by reaction of Al and Mg powder and water", Proceedings of 40th AIAA, SAE, pp.ASEE Joint Propulsion Conference and Exhibit, Fort Lauderdale, 2004
- Newman, J.N., "Marine Hydrodynamics" (1977), MITPress
- Park. S.H., "Development of practical method for prediction of cavitation erosion with turbulent flow using computational fluid dynamics", 박사, Dept. of Naval Architecture and Ocean Egineering, pp.2013
- Fabien Petitpas, "Modelling cavitating flow around underwater missiles", International Journal of Naval Architecture and Ocean Engineering, 3(4), pp.263~273 (2011), 대한조선학회
- Rouse, H., "Cavitation and Pressure Distribution Head Forms at Angles of Yaw. State University of Iowa", Studies in Engineering Bulletin, 32(420) (1948)
- Rabiee, A., "Part A: Experimental Investigation of Unsteady Supercavitating Flows", Iranian Journal of Science and Technology, Transactions of Mechanical Engineering, 35(M1), pp.15~29 (2011)
- Rabiee, A., "Part B: Numerical Investigation of Unsteady Supercavitating Flows", ranian Journal of Science and Technology, Transactions of Mechanical Engineering., 35(M1), pp.31~46 (2011)
- Experimental Investigation of Supercavitating Motion of Bodies, "Savchenko, Y.N.", von Karman Institute, ~ (2002)
- Semenenko, V. N., "Artificial Supercavitation, Physics and Calculation", Lecture Notes for RTO AVT, 2001
- Steady–State Cavity Studies in a Free-Jet Water Tunnel, "Self, M.W.", University of Minnesota, ~, pp.Report No. 47 (1955)
- 윤정수, "Study on self-pulsation characteristics of gas centered shear coaxial injector for supercavitating underwater propulsion system", International Journal of Naval Architecture and Ocean Engineering, 3(4), pp.286~292 (2011), 대한조선학회