工學院: 應用力學研究所指導教授: 周逸儒黃郁誠Huang, Yu-ChengYu-ChengHuang2017-03-062018-06-292017-03-062018-06-292015http://ntur.lib.ntu.edu.tw//handle/246246/277185本研究使用大渦流模式結合沉浸邊界法與移動網格法，模擬流體經過一具有圓孔的板子對圓孔下方靜止流體的混合效果，大渦流模式(Large eddy simulation)為三維的動力模式，較能捕捉到在高雷諾數下的紊流現象，在高雷諾數的流場中紊流現象特別重要，在卡氏座標系統即可很有效率的處理複雜幾何形狀或是移動網格的問題，另外在上方邊界移動的部分則使用移動網格法(Arbitrary Lagrangian-Eulerian scheme) 計算網格座標速度後模擬紊流現象，我們改變雷諾數與行程比模擬紊流流況，觀察出口速度隨時間的變化，確認邊界與流場速度符合Jennifer, et al.(2007)所做的實驗配置，設定邊界條件進行模擬，並且討論因邊界移動造成的流場變化與渦度的形成過程，以及紊流動能在流場中所扮演的角色。 為了觀測最單純的流場流況，並分析紊流動能在流場中的影響，模擬情況依照Z. Travnicˇek et al(2015)的模擬配置，將噴嘴出口速度當成模擬的邊界條件，不加入移動網格法與沉浸邊界法。In this study, we apply the large eddy simulation (LES) model along with the immersed boundary method (IBM) and the arbitrary Lagrangian-Eulerian method (ALE) to simulate the evolution of the synthetic round jet. The model is a three-dimensional incompressible flow simulator, which is capable of resolving the detailed turbulent flow field. We use the IBM to capture the effect of the solid surface. Compared to the traditional body-fitting methods, IBM applies the body force to satisfy the desired boundary conditions. It can efficiently handle the complex geometry in Cartesian coordinate system. In addition, we apply the ALE method which calculates the grid velocity of the moving boundary. The present numerical model is then validated against the experimental results. In addition, another simulation case that directly applies the measured velocity field at the jet orifice as the inlet boundary condition is conducted for a detailed numerical observation of the turbulent synthetic jet. Aspects in numerical setup to obtain the agreement with the experimental data are discussed. Moreover, simulated turbulent flow fields are carefully examined.3448582 bytesapplication/pdf論文公開時間: 2015/12/1論文使用權限: 同意無償授權大渦流模式沉浸邊界法移動網格法合成噴流紊流動能large-eddy simulationimmersed boundary methodarbitrary Lagrangian -Eulerian methodsynthetic jetturbulence kinetic energythesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/277185/1/ntu-104-R02543066-1.pdf