The most essential component in the cavitation flow is the pressure distribution in the flow line where the cavity closes. In this paper, the three-dimensional boundary element method (BEM) is employed to simulate the partial cavitation (cavitation number, σ between 0.1 to 0.5) around projectiles with different cavitators. The effects of the size of quadrilateral elements on the results of cavity geometry and on the distribution of pressure coefficient obtained by three-dimensional boundary element method are investigated for different kinds of spherical and conical cavitators. It should be noted that choosing a small size of the element cannot certainly lead to accurate results in BEM. Accordingly, based on a comparison of the experimental data with the BEM results, a function of element size is proposed based on the variables of cavitator shape and cavitation number. A comparison of the BEM predictions with the numerical simulation results in ANSYS Fluent software is given. The analysis indicates that satisfactory values can be found for the cavity dimensions and pressure distributions virtually in a few minutes by using BEM with specific quadratic elements.

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