平行計算應用於多重與單一鬆弛時間晶格波茲曼模型

Parallel implementation of multi and single relaxation time lattice Boltzmann methods

陳顗丞(Yi-Cheng Chen)

指導教授 ： 林昭安

國立清華大學/工學院/動力機械工程學系/碩士(2010年)

https://doi.org/10.6843/NTHU.2010.00362

摘要

In this thesis, the validity of the adopted MRT lattice Boltzmann model [14] is examined by computing two-dimensional Poiseuille flow, lid-driven cavity flow, and three-dimensional Poiseuille flow in a square duct. We also use the density fluctuation and assume the mean density to reduce effects due to compressibility [48]. The present simulation indicates that SRT method fails to simulate higher Reynolds number flows due to the limitation of tau value. In contrast to the SRT method, the tau value for MRT method can be close to 0.5 for 2-D and 3-D simulations owing to the different relaxation rates. It should be noted that 3D MRT computations are very sensitive to boundaries, especially the treatment of the corners and edges. As adopting smaller value of tau combined with MRT method, higher Reynolds number flow can be realized. Finally, parallel-MRT and parallel-SRT models are implemented for large grid density simulations, and simulated results are presented.

關鍵字

晶格波茲曼模型 ； 多重鬆弛時間 ； 平行計算 ； 高雷諾數流場

並列摘要

無資料

並列關鍵字

lattice Boltzmann method ； MRT ； parallel computation ； high Reynolds number flow

參考文獻

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