不同流體在傾斜角度之封閉矩形空間中二維自然對流現象研究

Study of 2D Natural Convection Heat Transfer in a Inclined Rectangular Enclosure Filled with Different Fluids

鄭鴻斌(Hong-Bin Zheng)

國立虎尾科技大學/工程學院/機械與機電工程研究所/碩士(2007年)

摘要

本文以數值模擬分析與實驗量測方式探討不同流體在封閉矩形空間中自然對流熱傳導現象。運用Jou[9]所建立之Fortran程式數值分析矩形空間中之2D流場分析。實驗所用之理論模型，為一邊為冷卻端另一邊為加熱端，其餘邊界皆為絕熱壁，在理論模型關係式中，將空氣、純水、混合流體(水跟乙二醇)隨著溫差、體積百分比變化之熱傳率效應以及不同傾斜角度列入考慮，數值模擬主要考慮參數範圍為：葛拉秀夫數(Gr=103~106)；普蘭特數(Pr=0.71、6.2、62.4)分別為空氣、純水、混合流體；奈米流體為奈米銅加入水跟乙二醇的混合溶液；傾斜角度(0°~360°)；實驗量測考量有限溫差下隨著傾斜角度(0°、45°及315°)於不同流體之自然對流現象。並以雷射觀察其不同流體於傾斜角度下之自然對流流線場。

並列摘要

The problem of two-dimensional steady state natural convection heat transfer in a rectangular enclosure filled with different fluids has been investigated numerically and experimentally. Use fortran of Jou[9] set up to 2D flow field analyse. It’s about putting the air, water, mixture fluids(water/EG) in a rectangular enclosure container which has two sides. One of it is Cooling Surface, another is Heating Surface, and others are Adiabatic Surfaces. In the numerical formulation, the effects of variable heat transfer of the fluids associated with temperature and gravity. The numerical simulations have been undertaken for the pertinent dimensionless parameters in the following ranges: the Grashof number Gr=103~106; the Prandtl number, Pr=0.71、6.2、62.4, It is air, water, mixture fluids(water/EG); degree(0°~360°); experimental consideration limited temperature difference along with angle of tilt (0°, 45°and315°) of natural convection phenomenon to air, water, mixture fluids. The experimental result is by laser watching stream function.

參考文獻

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