An Estimation of the Size of Supercavities for Conical Cavitators

- Journal title : Journal of the Society of Naval Architects of Korea
- Volume 53, Issue 2, 2016, pp.92-100
- Publisher : The Society of Naval Architects of Korea
- DOI : 10.3744/SNAK.2016.53.2.92

Title & Authors

An Estimation of the Size of Supercavities for Conical Cavitators

Kim, Hyoung-Tae; Kim, Byeung-jin; Choi, Jung-Kyu; Yoon, Hyun-Gull;

Kim, Hyoung-Tae; Kim, Byeung-jin; Choi, Jung-Kyu; Yoon, Hyun-Gull;

Abstract

A comparative method is applied to evaluate well-known formulas for estimating the size of supercavities of axisymmetric cavitators for the supercavitating underwater vehicle. Basic functional forms of these formulas are derived first for the cavity diameter from a momentum integral estimate and second for the cavity length from an asymptotic analysis of inviscid supercavity flows. The length and the diameter of axisymmetric supercavities estimated by each formula are compared, with available experimental data for a disk and a 45° conical cavitators, and also with computational results obtained by a CFD code, ‘fluent’, for conical cavitators of wide range of cone angles. Results for estimating the length and the diameter of the supercavities show in general a good agreement, which confirms the size of the supercavities for disk and conical cavitators can be estimated accurately by these simple formulas of an elementary function of cavitation number and drag coefficient of the cavitator. These formulas will be useful for from conceptual design of the cavitator to real-time control of the supercavitating underwater vehicle.

Keywords

Conical Cavitators;Estimation of the Size of Supercavities;

Language

Korean

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