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A study on practical method to estimate drag of super-cavitating underwater vehicles

  • Choi, Jung-Kyu (Department of Naval Architecture & Ocean Engineering, Mokpo National University) ;
  • Kim, Hyoung-Tae (Department of Naval Architecture & Ocean Engineering, Chungnam National University)
  • Received : 2021.07.20
  • Accepted : 2021.10.31
  • Published : 2021.11.30

Abstract

In this paper, a simple practical method to estimate the drag of Super-Cavitating Underwater Vehicles (SCUV) is proposed that can obtain the drag with only principal dimensions in an initial design stage. SCUV is divided into cavitator, forebody, afterbody, base, and control fin and the drag of each part is estimated. The formulas for the drag coefficient are proposed for the disk and cone type cavitators and wedges used as control fins. The formulas are a function of cavitation number, cone or wedge angle, and Reynolds number. This method can confirm the drag characteristics of SCUV that the drag hump appears according to the coverage of the body by the cavity and the cavitator drag remains only when the entire body is covered by cavity. Applying this method to SCUV of various shapes, it is confirmed that the effects of cavitating and non-cavitating conditions, cavitator and body shape, and speed could be found.

Keywords

Acknowledgement

This work was carried out with the support of Agency for Defense Development (ADD) of Korea under the project (A numerical analysis of super-cavitation shape and hydrodynamic force for a super-cavitating underwater vehicle).

References

  1. Ahn, B.K., Lee, T.K., Kim, H.T., Lee, C.S., 2012. Experimental investigation of supercavitating flows. Int. J. naval Architecture Ocean Eng. 4 (2), 123-131. https://doi.org/10.3744/JNAOE.2012.4.2.123
  2. Alyanak, E., Venkayya, V., Grandhi, R., Penmetsa, R., 2004. Variable shape cavitator design for a super- cavitating torpedo. In: Proceedings of 10th AIAA/ISSNMO Multidisciplinary Analysis and Optimization Conference AIAA 2004-4424. Submitted for publication.
  3. Choi, E.J., 2018. Numerical study of unsteady cavity flow for underwater body in accelerated translation motion. Master's thesis Chungnam National University 60-73.
  4. Choi, J.K., Ahn, B.K., Kim, H.T., 2015. A numerical and experimental study on the drag of a cavitating underwater vehicle in cavitation tunnel. Int. J. naval Architecture Ocean Eng. 7, 888-905. https://doi.org/10.1515/ijnaoe-2015-0062
  5. Choi, E.J., Kim, H.T., Yoon, H.G., 2017. A numerical study on unsteady supercavitation and drag of an underwater vehicle applying a linearly increasing trust. In: Proceedings of KSPE Fall Conference 2017. The Korean Society of Propulsion Engineers, pp. 81-82.
  6. Epshtein, L.A., 1971. Characteristics of ventilated cavities and some scale effects. Proc. Of IUTAM Symposium on Rapid Non-steady Liquid Flows, pp. 173-185. Leningrad, 22-26 June 1971.
  7. Franc, J.P., Michel, J.M., 2004. Fundamentals of Cavitation. Kluwer Academic Publishers, Dordrecht.
  8. Garabedian, P.R., 1956. Calculation of axially symmetric cavities and jets. Pac. J. Math. 6 (4), 611-684. https://doi.org/10.2140/pjm.1956.6.611
  9. Guzevsky, L.G., 1983. Approximation Dependencies for Axisymmetric Cavities past Cones. In: Hydrodynamic flows and wave processes. [in Russian], Institute of Thermal Physics, Sib. Branch, Acad. of Sci. of the USSR, Novosibirsk, pp. 82-91.
  10. Hoerner, S.F., 1965. Fluid-Dynamic Drag. Hoerner Fluid Dynamics: CA, USA.
  11. Kim, H.T., Lee, H.B., Choi, J.K., 2015. Numerical analysis of the drag of conical cavitators. J. Soc. Naval Architect. Korea 52 (4), 305-314. https://doi.org/10.3744/SNAK.2015.52.4.305
  12. Kim, H.T., Kang, K.T., Choi, J.K., Jung, Y.R., Kim, M.J., 2018. A numerical study of effects of body shape on cavity and drag of underwater vehicle. J. Soc. Naval Architect. Korea 55 (3), 252-264. https://doi.org/10.3744/SNAK.2018.55.3.252
  13. Kim, H.T., Choi, E.J., Kang, K.T., Yoon, H.G., 2019. Numerical analysis of the cavitation around an underwater body with control fins. J. Soc. Naval Architect. Korea 56 (4), 298-307. https://doi.org/10.3744/SNAK.2019.56.4.298
  14. Kirschner, I.N., 2001. Results of selected experiments involving supercavitating flows. In: RTO AVT Lecture Series on Supercavitating Flows, vols. 12-16. von Karman Institute. February, 2001, RTO EN-010.
  15. Knapp, R.T., Daily, J.W., Hammit, F.G., 1970. Cavitation. Iowa Institute of Hydraulic Research, University of Iowa, Iowa, USA.
  16. Lee, H.B., Choi, J.K., Kim, H.T., 2012. A numerical study on the drag of axial cylinder. J. Soc. Naval Architect. Korea 49 (6), 512-520. https://doi.org/10.3744/SNAK.2012.49.6.512
  17. Lee, H.B., Choi, J.K., Kim, H.T., 2013. Numerical analysis of supercavitating flows of two-dimensional simple bodies. J. Soc. Naval Architect. Korea 50 (6), 436-449. https://doi.org/10.3744/SNAK.2013.50.6.436
  18. Logvinovich, G.V., 1969. Hydrodynamics of free surface flows. In: Dunka, Nauvoka (Ed.), Russian), Kiev (Ukraine).
  19. Newmann, J.N., 1977. 5. Lifting Surfaces. Marine Hydrodynamics. The MIT Press.
  20. Reichardt, H., 1946. The laws of cavitation bubbles at axially symmetric bodies in a flow. Ministry of Aircraft Production Volkenrode, MAP-VG, Reports and Translations 766. Office of Naval Research, USA.
  21. Rouse, H., Mcnown, J.S., 1948. Cavitation and pressure distribution head forms at angles of Yaw. Studies in Engineering Bulletin. State University of IOWA, p. 32.
  22. Savchenko, Y.N., 2001. Experimental investigation of supercavitating motion of bodies. RTO AVT Lecture Series on Supercavitating Flows. VKI in Brussels, Belgium, pp. 12-16. February 2001.
  23. Schlichting, H., 1979. Boundary Layer Theory, seventh ed. McGraw-Hill, USA.
  24. Self, M.W., Ripken, H.F., 1955. Steady-state Cavity Studies in a Free-Jet Water Tunnel. University of Minnesota, Minnesota, USA. St. Anthony Falls Hydraulic Laboratory, University of Minnesota, Report No. 47.
  25. Semenenko, V.N., 2001. Artificial Supercavitation, Physics and Calculation. RTO AVT Lecture Series on Supercavitating Flows, VKI in Brussels, Belgium, pp. 12-16. February 2001.
  26. Waid, R.L., 1957. Water Tunnel Investigation of Two-Dimensional Cavities. California Institute of Technology Hydrodynamics Laboratory. Report No. E-73.6.
  27. Yoon, H.G., Lee, H.N., Cha, J.M., Lim, S., Suh, S.H., 2018. Measurement of performance of high speed underwater vehicle with solid rocket motor (II). J. Korea Soc. Propulsion Eng. 22 (4), 12-17. https://doi.org/10.6108/KSPE.2018.22.4.012