非結構性寬頻元素法應用於二維不可壓縮流場之研究

Applying Unstructured Spectral Element Method to Simulate Two Dimensional Incompressible Flow

簡志偉(Zh-Wei Jian)

指導教授 ： 顏瑞和

國立臺灣大學/工學院/機械工程學研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.01955

摘要

本文目的在於利用寬頻元素法和分步驟法來解二維不可壓縮之流場問題，文中所使用之網格類型為非結構性網格。因為是二維問題所以主要是三角形網格。基於上述的方法，我們發展了一套計算程式來用以模擬計算二維之流場問題，並透過具有解析解之Kovasznay流和一自訂解析解之暫態流場來對所發展之程式進行驗證和相關數值性質之探討。最後使用已驗證完畢的程式進行真實流場之模擬，包括穴流(driven-cavity flow)、突張流(sudden-expansion flow)和圓柱流(cylinder flow)，並將計算之結果與相關文獻作比較以驗證計算結果之正確性。

關鍵字

寬頻元素法 ； 分步驟法 ； 非結構性網格 ； 三角形網格 ； Kovasznay流 ； 穴流 ； 突張流 ； 圓柱流

並列摘要

This research is to simulate two dimensional incompressible flow with spectral element method and splitting scheme. We utilize the unstructured element as our mesh type, triangular element is mainly used in this article. Base on these method, we develop a program to simulate two dimensional incompressible flow. Then using Kovasznay flow and transient flow which have exact solutions to verify the simulating program and relative numerical properties. Finally applying the developed program to obtain numerically some results of real fluidic field, include driven-cavity flow、sudden-expansion flow and cylinder flow. To verify the program via compare these results with relative papers, we find that the error of results is accepted.

並列關鍵字

spectral element method ； splitting scheme ； unstructured element ； triangular element ； Kovasznay flow ； driven-cavity flow ； sudden-expansion flow ； cylinder flow

參考文獻

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