本論文以元素疊代（Element-by-Element）為基礎的投射有限元素流體解析法（projection finite element fluid analysis）為主，對於均勻紊流流過二維強制對流通道之散熱片的暫態流動及其傳熱現象進行分析。以EBE-PCG投射有限元素法取代以往有限元素法解無因次之Navier-Stokes Equation及能量方程式，乃是為了能減少矩陣的儲存量，及減少電腦上的計算時間。並且運用Large Eddy Simulation的紊流模式來模擬紊流流場，以前置處理之共軛梯度法（preconditioned conjugate gradient method）加以疊代而解出其速度場，壓力場和溫度場。
　　本文提供一套EBE-PCG數值模擬二維風道內強制對流之散熱片。目的在不同風向角、不同葉片密度及不同雷諾數下，求得通道流場中的速度場、壓力場及溫度場。研究結果顯示:
（1）紐賽數Nu、阻力係數CD與升力係數CL值會隨著雷諾數增加而 變大。
（2）低鳍片密度在低雷諾數下紐賽數Nu值要比高鳍片密度好。隨雷諾數增加，兩者的紐賽數Nu值會越來越接近。
（3）散熱片在風向角0度時比在風向角90度時，有較佳的散熱能力。

　This paper used Element-by-Element projection finite element for uniform turbulent flow in a 2D forced convection channel with heat sinks. Using Element-by-Element finite element preconditioned conjugate gradient method replaces the traditional finite element method for the non-dimensional Navier-Stokes Equation and Energy Equation. It can reduce matrix storage and computational time. Using large eddy simulation method turbulent model simulates turbulent flow with preconditioned conjugate gradient method for iterating process to obtain velocity field, pressure filed, and temperature field.

This paper offered a set of EBE-PCG numerical simulation method to simulate 2D heat sinks in a forced convection channel. The main purpose of this study is to find velocity field, pressure filed, and temperature field under different flow angle, different fin densities and different Reynolds number. The results show:

（1）The Nusselt number, the drag coefficient and the lift coefficient will increase with increasing Reynolds number.

（2）The Nusselt number at a low fin density is better than a high fin density under the low Reynolds number, and both of the Nusselt number will be getting close with increasing Reynolds number.

（3）The heat sinks have better heat dissipation ability in 0 degrees of the flow angle than in 90 degrees of flow angle.

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