為了要模擬噴嘴內氣泡震波空蝕現象的發生，在數值模擬方面本文採用了ROE的通量分離法。以推導原始的ROE方程後改寫成代數式的型式，而以此方法可以提高運算的效率。空間離散則使用Muscl+Limiter，而在時間離散上採用具TVD效應之三階Runge-Kutta法。吾人以代數式型式的ROE模擬一維的震波管及爆炸波問題作驗證，得到的結果與真實黎曼解幾乎是一致的。接著模擬二維的噴嘴，在採用 紊流模式時能模擬出週期性變化，及空蝕係數大於1.5後可抑制空蝕氣泡的產生。最後模擬二維及軸對稱注油器，則可看出兩者氣泡震波發生的位置與時間有明顯的差異性。在未來則是希望進行三維測試例的模擬。 The purpose is to simulate the shock-like cavitation phenomena in the nozzle flow. Numerical simulation is based on the Roe type flux splitting method. The original ROE solver is reformulated in the algebraic form. This reformulated method can enhance the efficiency of the computations. Also, the MUSCL type method is used to deal with spatial discretization and a 3-order Runge-Kutta method is chosen to discretize the time evolution. First, one-dimensional shock tube and blast wave problems are validated with numerical calculations. Secondly, the turbulence model can achieve the periodical revolution of bubble growths of two-dimensional cavitated nozzle flows. In addition, the flow under the cavitation number more than 1.5 is shown that the cavitation will not appear in the nozzle. Finally, the two-dimensional and axis-symmetric injector nozzle cases show that the different location and appearing time for the shock-like cavitated flow are captured. The three-dimensional test cases will be necessary in the further study.
