在本研究中採用了多鬆弛時間晶格波茲曼法模擬雷諾數為700以及2800的週期性山坡紊流流場。在晶格波茲曼法中，通常都是採用均勻網格，因此在處理流場中的複雜幾何圖形時，曲面修正的方式十分重要。但在進行曲面修正時，流場的整體密度可能因此增加或減少，進而破壞流場的穩定。由此可知，需要對密度進行補償以保證流場中的質量守恆。除了檢驗流場的密度是否守恆，本研究將BFL以及Q correction兩種曲面修正方式進行比較。在網格的部分也使用不同密度的網格得到相同的結果。最後，本研究使用高速圖形顯示卡叢集進行運算，並採用二維切割以達到加速的效果

In present work, multi-relaxation-time lattice Boltzmann method (LBM) was adopted to investigate turbulent flow over periodic hills. The Reynolds numbers based on the hill height and bulk velocity were 700 and 2800. In LBM, uniform grids were the most common case, where curved boundary treatments are needed to investigate the case with complex geometries in the flow field. However, implementing curved boundary treatments could make the mass of the system decrease or increase and then sabotage the stability of the flow field. As a result, mass-conservative implementation is necessary to fix the mass leakage. Apart from the examination of mass conservation, the capability of different curved boundary treatments, which were BFL scheme and Q corrections, were adopted and compared with benchmarks. In addition, different sets of grids were adopted to identify the grid independence. Finally, the simulations were conducted on multi-GPU clusters with two dimensional decomposition to accelerate the computation

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