本文主要針對侷限衝擊噴流之共軛熱傳做數值模擬，並採用Li及Garimella (2001) 實驗數據來分析穩態二維、紊流流場與熱傳的數值模擬以驗證理論模式之可行性。本文紊流統御方程式乃是以控制體積法為基礎，配合有限差分法及冪次法則來離散成差分方程式。對於紊流的結構則是以 紊流模式配合牆函數來描述。並以SIMPLE運算法則求解壓力-速度結合的問題。
本文的參數包含噴口口徑 (d=3~6mm)，紊流雷諾數 (Re=4000~23000)，噴口至加熱片的距離 (H/d=2~4)，工作介質為水。本文中氣-液自由表面的幾何形狀是由疊代的方式來決定。本文以速度向量圖與紊流層次來表示在侷限流場之迴流現象，噴嘴出口噴流的發展，以及沿著衝擊表面流體的發展。結果顯示，除了雷諾數Re，噴口至加熱表面的間距(H/d)對於溫度分佈及紐賽數均有顯著的影響。 之預測方面，再加熱片段的表面上熱傳係數低估超過100﹪，此低估預測相信是由於在此區域紊流動能的低估所致。

This study presents the numerical simulation of conjugate heat transfer of confined impinging jet, based on the experiment results of Chin-Yuan Li and Suresh V. Garimella (2000). The numerical simulation of steady, two dimensional, turbulent flow and heat transfer is adopted to test the accuracy of the theoretical model. The turbulent-governing equation are resolved by Control-Volume based finite-different method with power-low scheme, and the well-known turbulence model and its associate wall function to describe the turbulent structure. The SIMPLE algorithm is adopted to solve the pressure-velocity coupling.
The parameters studied include orifice diameter d=3~6mm, turbulent flow Reynolds number Re=4000~23000, and orifice to heat-source spacing H/d=2~4, and the working medium is water. The geometry of the free surface was determined iteratively. Velocity vector contour and turbulence levels are presented to describe the flow field in the recirculation pattern in the confined outflow, the development of the jet after exiting the nozzle and the development of the flow along the impingement surface. It is found that in addition to jet Reynolds number (Re), and orifice to heated surface spacing (H/d) have significant influence on temperature distribution and Nusselt number (Nu).Quantitatively， predictions underestimate the surface heat transfer above the heated surface by more than 100﹪. This underprediction is believed to be due to the underprediction of turbulent kinetic energy in that region.

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