Unsteady forces and moments acting on a cantilevered rectangular hydrofoil with tip clearance in cavitating conditions

Yushin Ehara, Soichiro Kitamura, Wakana Tsuru, Satoshi Watanabe, Shin Ichi Tsuda

Research output: Contribution to journalConference article

Abstract

It is known that the lift and drag forces of hydrofoil increase then decrease with the decrease of cavitation number, i.e. the development of cavitation, in many cases. In our previous study, the measurement of lift and drag forces of cavitating Clark Y-11.7% hydrofoil was conducted under the assumption of two-dimensional flow, which showed the similar tendency to above common knowledge. However, since there was a tip clearance, the bending moment should present to some content due to the flow asymmetry. In the present study, by using hydrofoil supported by a cantilever equipped with totally 8 strain gauges, the lift and drag forces and their moments are separately measured. It is found that the time-averaged moments around midspan due to lift and drag forces change with the decrease of cavitation number as well as the lift and drag forces change. This means that the working points of lift and drag forces move in the spanwise direction, indicating the importance of the three-dimensionality of cavitation development including that due to tip clearance flow. Unsteady lift and drag forces and their moments also show the significant fluctuations due to periodic behaviour of cavitation instabilities.

Original languageEnglish
Article number062054
JournalIOP Conference Series: Earth and Environmental Science
Volume240
Issue number6
DOIs
Publication statusPublished - Mar 28 2019
Event29th IAHR Symposium on Hydraulic Machinery and Systems, IAHR 2018 - Kyoto, Japan
Duration: Sep 16 2018Sep 21 2018

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drag
cavitation
two-dimensional flow
gauge
asymmetry

All Science Journal Classification (ASJC) codes

  • Environmental Science(all)
  • Earth and Planetary Sciences(all)

Cite this

Unsteady forces and moments acting on a cantilevered rectangular hydrofoil with tip clearance in cavitating conditions. / Ehara, Yushin; Kitamura, Soichiro; Tsuru, Wakana; Watanabe, Satoshi; Tsuda, Shin Ichi.

In: IOP Conference Series: Earth and Environmental Science, Vol. 240, No. 6, 062054, 28.03.2019.

Research output: Contribution to journalConference article

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