캐비테이션 침식 추정을 위한 실용적인 기법 개발

다국어 초록 (Multilingual Abstract)

Cavitation erosion can be observed on hydraulic mechanical devices and has long been studied, yet a difficult research subject for many years. In the present study, the practical formula to predict the cavitation erosion was developed, and the CFD analyses were performed to determine the cavitation erosion coefficient. Cavitating flows were studied using an Reynolds-averaged Navier-Stokes solver based on a cell-centered finite volume method. To verify and validate cavitating flows, sheet, cloud and super cavitating flows were simulated and compared against existing experimental data. Through the simulations, the computational methods were studied carefully and the simulation of cavitating flows was validated. The cavity length and surface pressure distribution were compared with experimental data and analytic solutions.
To develop the cavitation erosion coefficient, cavitating flows in a converging and diverging nozzle and around a hydrofoil were simulated. Cavitation erosion extents were studied for various cavitating flow conditions including various cavitation and Reynolds numbers. By comparison with, existing experimental data, a practical equation for the prediction of cavitation erosion, which is a function of the cavitation number, was developed. The developed practical formula helps predict cavitation erosion observed on the blades of pumps, turbines, and marine propellers.