Journal of the Korea Institute of Military Science and Technology (한국군사과학기술학회지)

The Korea Institute of Military Science and Technology (한국군사과학기술학회)
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Influence of a Large-Eddy Breakup Device on Drag of an Underwater Vehicle

Large-Eddy Breakup Device가 수중운동체의 저항에 미치는 영향

  • Kim, Joon-Seok (Maritime Technology Research Institute, Agency for Defense Development)
  • 김준석 (국방과학연구소 해양기술연구원)
  • Received : 2019.07.25
  • Accepted : 2019.09.13
  • Published : 2019.12.05
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Abstract

A numerical analysis of a turbulent flow with a 'large-eddy breakup device(LEBU)' was performed to investigate the influence of the device on the drag of underwater vehicle using commercial CFD code, FLUENT. In the present study, the vehicle drag was decomposed to skin-friction coefficient(Cf) and pressure coefficient(Cp). The variation of the vehicle Cf and Cp were observed with changing location of the device and Reynolds number. As a result, the device decreased the vehicle Cf because it suppressed the turbulent characteristics behind the device. The larger Reynolds number, the higher reduction effect when the device was placed in front part of, and near the vehicle. On the other hand, the device increased/decreased the vehicle Cp with increasing/decreasing turbulent kinetic energy at recirculating flow region behind the vehicle. The total drag change by the device was caused by Cp rather than Cf.

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References

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