可調式算則在空蝕現象的模擬應用

Application of Preconditioned Method on the Simulation of Cavitating Flows

王瀚鋐(Han-Hung Wang)

指導教授 ： 牛仰堯

淡江大學/工學院/航空太空工程學系碩士班/碩士(2013年)

https://doi.org/10.6846/TKU.2013.00319

摘要

本文目的為發展一個非穩態可壓縮多相流含空蝕現象的數值模式。如我們所知，在多相流的計算分析中，不同流體的界面捕捉以及模擬相變化的過程仍然是極大的挑戰。本文將以混合守恆之多相可壓縮Navier-Stokes方程式做為統御方程式，並模擬不可壓縮及可壓縮全流域。我們加入預調法模擬相變化的過程，數值方法則採取Weiss and smith等人[18]所發展出來Precodtion方法，並結合Roe的數值通量分離法處理空間通量的離散，以4階Runge-Kutta method處理時間離散，使程式能在數值穩定與計算時間上求得較佳之平衡。本文驗證之例子為準一維水噴嘴流道以及二維鈍頭體空蝕現象的分析，分析結果與相關實驗的數據比對均能獲得令人滿意的驗證。

關鍵字

兩相流 ； 空蝕現象 ； 預調法

並列摘要

The purpose is to develop an unsteady compressible multiphase flow cavitation numerical model. As we know, capturing different fluid interface and simulating phase change process are still a great challenge in the calculation analysis of multiphase flow. This paper use mixing conservation equations of multiphase compressible Navier-Stokes as governing equations. we adopt preconditioned method to simulate phase change process. Numerical methods are taken Precondition method by Weiss and smith et al [18] developed. And we adopt Roe’s flux splitting method to deal with flux discretization in space. A dual-time implicit formulation with 4-order Runge-Kutta method is employed to accommodate the inherently unsteady physics. The program will enable the numerical stability and computation time obtained a better balance. In this thesis, examples of verifications are 1-d nozzle of the flow path and 2-d blunt body cavitation analysis and the results compared with the experimental data can obtain satisfactory for verification.

並列關鍵字

Two-Phase ； Cavitation ； Preconditioning

參考文獻

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