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。

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.

致謝	i
中文摘要	ii
英文摘要	iii
目錄	iv
表目錄	vi
圖目錄	vi
符號說明	vii
第一章	緒論	1
1.1	前言	1
1.2	空蝕係數物理意義	1
1.3	文獻回顧	4
1.4	研究目的	6
第二章	數值計算方法	8
2.1	統御方程式(Governing Equations)	8
守恆方程式	8
預調法(Preconditioning)	9
2.2	狀態方程式	10
I.	液體狀態	11
II.	氣體狀態	11
3.3	數值方法	12
i.	Preconditioning Roe 算則	12
ii.	Modified Preconditioning Roe算則	15
3.4	紊流模式	17
i.	Spalart-Allmaras紊流模型	17
ii.	標準 k-ε 紊流模型	17
3.5	空蝕模式	18
i.	Zwart-Gerber-Belamri 模型	19
ii.	Schner-Suaer模型	21
第三章	結果與討論	23
3.1	準一維水噴嘴之數值分析	23
3.2	二維鈍頭體空蝕模擬	28
3.2.1	不同的紊流模式的結果之比較	32
3.2.2	不同的空蝕模式的結果之比較	34
3.3	二維突縮管空蝕模擬	36
第四章	結論	41
參考文獻	43

表目錄	
表 1準一維噴嘴入口與邊界條件 	24
表 2二維鈍頭體流體條件 	29
表 3  S-A Model預設參數值 	32
表 4  Standard k-ε Model預設參數值 	32

圖目錄
圖 1準一維噴嘴的空蝕現象 	27
圖 2準一維噴嘴空蝕現象的收斂過程 	28
圖 3二維鈍頭體流場網格圖 	29
圖 4二維鈍頭體空蝕現象的密度分布與速度粒子軌跡圖 	31
圖 5不同紊流模型的鈍頭體表面壓力係數分佈 	33
圖 6不同空蝕模型的鈍頭體表面壓力分佈 	36
圖 7二維突縮管網格圖 	37
圖 8不同紊流模式的突縮管下壁面速度分布圖 	39
圖 9二維突縮管空蝕現象之蒸汽體積佔有率 	39

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