本文主要以數值模擬衝擊噴流冷卻下靜止與旋轉鰭片散熱器的流場與熱傳特性。文中選用5x5的方型柱狀鰭片散熱器來進行模擬，且工作流體為空氣。紊流統御方程式是應用有限體積法配合四種根據雷諾平均Navier-Stokes近似的紊流模式來求解，在本文所研究的範圍內，標準k-epsilon紊流模式在整體性能表現較好。
往後的數值計算都使用標準k-epsilon模型，其研究參數包含：相對的衝擊高度(C/d)、相對的鰭片寬度(w/d)、相對的鰭片高度(Hf/d)、雷諾數(Re)和旋轉雷諾數(Rer)，其研究探討的範圍為0<C/d<11、0.31<w/d<0.77、1.54<Hf/d<3.08、5019<Re<25096和3478<Rer<8114，且所發展的理論計算結果並與文獻上的實驗數據作驗證。
文中將計算衝擊高度(C/d)、雷諾數(Re)和旋轉雷諾數(Rer)對靜止與旋轉鰭片散熱器系統之平均紐賽數(Nu)的影響，且與實驗比對得到一致的結果，文中也提供平均紐賽數(Nu)的經驗公式。具衝擊噴流的旋轉鰭片散熱器方面，文中探討Rer對平均紐賽數(Nu)的影響，其計算結果顯示當Re較小(Re=5019)時，熱傳增益有明顯的提升，但當Re增加，其熱傳增益則會下降。
此外，在數值驗證後，文中並利用反應曲面法(response surface methodology)、全因子法(full factorial experimental design)和基因演算法(genetic algorithm method)來探討本問題的最佳化。對於靜止與旋轉鰭片散熱器，其最佳化設計的結果是在C/d=0、w/d=0.77和Hf/d=3.08。

In this study, the fluid flow and heat transfer characteristics of jet impingement onto the stationary and rotating heat sink have been investigated numerically. The square heat sinks with uniformly in-line arranged of 5x5 pin-fins are employed and the impinging coolant is air. The turbulent governing equations are solved using finite volume method by employing four turbulence models based on Reynolds-averaged Navier-Stokes(RANS) approach. Overall performance of standard k-epsilon models is better in comparing with other models in the studied ranges.
Subsequent numerical computations are performed with standard k-epsilon models for the parameters studied relative distance of nozzle to fin tip(C/d), relative width of the fin(w/d), relative height of the pin-fins(Hf/d), Reynolds number(Re) and rotational Reynolds number(Rer) in the ranges of 0<C/d<11, 0.31<w/d<0.77, 1.54<Hf/d<3.08, 5019<Re<25096 and 3478<Rer<8114 respectively. The theoretical model developed is validated by comparing with the available experimental data in the literature.
The effects of C/d, Re and Rer on the average Nusselt number(Nu) for the stationary and rotating heat sink system are in good agreement with the available data and the correlation equations of average Nusselt number(Nu) are also provided. The effects of Rer on the average Nusselt number(Nu) of a rotating heat sink with jet impingement, the results demonstrate that the heat transfer enhancement( is obvious in the case of smaller Re(Re=5019), but decreased with increasing Re.
In addition, after the validation of the numerical results, the optimization of this problem is also presented by using response surface methodology(RSM), full factorial experimental design and genetic algorithm(GA) method. Based on the results derived by the optimization, the optimum condition is in C/d=0, w/d=0.77 and Hf/d=3.08 for stationary and rotating pin-fins heat sink.

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