本文之目的在於以CIP(Cubic Interpolated Profile)法模擬自由液面及其流場變化，探討CIP法在不同粗細的網格捕抓自由液面情況，並研究黏滯力對流場的影響。流場控制方程式以三階準確的CIP法和二階準確有限體積中央差分分段計算，壓力部分的Poisson equation使用SOR(Successive Over-Relaxation)求解，黏滯項則以有限體積中央差分法去離散。

　　模擬的物理問題為水壩潰堤和水珠掉落，首先以水壩潰堤驗證本程式的準確性和可靠性，再以水珠掉落探討本程式對曲面的模擬能力，並加入黏滯力的效應觀察流場變化，由模擬結果可知 CIP法對自由液面波形特性模擬效果佳，尤其加入黏滯力的粗網格其液面仍可維持一定平滑度；加入黏滯力使得動能消散，整個流場速度相較於無黏滯力的緩和，在水珠掉落的實驗中，更發現黏滯力對自由液面外形有其影響存在。

　　The objective of this study aims at predicting the interfacial flow field with the CIP(Cubic Interpolated Profile) method. Influences of the grid-mesh resolution on the surface-capturing capability and of the consideration of the viscous term on the prediction accuracy of flow field are investigated. The governing equations can be split into the advection and non-advection term by the time splitting method, in which the advection terms are simulated using the CIP method with the third-order spatial accuracy, while the non-advection terms are discretized using the second-order cell-center finite-volume scheme. The Poisson equation for pressure field is solved using the SOR (Successive Over-Relaxation )method. The diffusion term is discretized by the second-order cell-center finite-volume scheme.

　　Two test problems including a two-dimensional dam break problem and a problem of falling droplet on water surface are studied. The dam break problem in which these exists available experimental data is firstly studied to validate the computer model. Next, the simulation of the problem of falling droplet on water surface is performed by taking into consideration with and without the viscous effect. It is found that the CIP method is capable of capturing the free surface even with a coarse grid mesh with consideration of the viscous effect. Inclusion of the viscous effect in the modeling facilates smoothening the velocity distribution as compared to the simulation without considering the viscous effect. It is found that the viscous effect becomes more significant in the simulation of the free surface shape on the problem of falling on water surface.

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