封閉盒中不同位置之阻礙物對熱質對流的影響與探討

Investigation of thermosolutal convection in an enclosure with obstacle inside at different locations

蔡宏源(Hung-Yuan Tsai)

指導教授 ： 王立文

元智大學/工程學院/機械工程學系/碩士(2008年)

https://doi.org/10.6838/YZU.2008.00076

摘要

本研究主要是藉由實驗方法來探討一個左，右為銅板，上下為壓克力塊之封閉盒。並且在密閉盒中設置一個阻礙物，觀察由溫度梯度與濃度梯度所引起的熱質自然對流現象。本次的實驗區域，利用其幾何形狀與邊界條件的設計，使得在實驗中可以觀察到不同位置之阻礙物在密閉盒中對於流場的影響，並針對相關無因次參數來探討密閉區域內的流場結構。
實驗工作流體為濃度0.05M的硫酸銅水溶液(CuS04+H2SO4+H2O)。溫度梯度是由兩個不同溫度的恆溫水槽來維持，濃度梯度則利用電化學系統來建立，於左，右兩銅板加上電壓，使其成為不同電極造成濃度梯度。
流場的觀察是採用雷射光暗影法(shadowgraph)，並且以相機拍照紀錄，以利分析。並對流場做溫度量測及濃度分佈的量測。有系統的探討對相關無因次參數Grm、Grt與質傳遞率Sh值對其流場結構的影響，並對不同位置之阻礙物與不同溫度之銅板之流場現象做觀察。並改變流場順逆向與傾斜角度。

關鍵字

封閉盒 ； 熱質對流 ； 阻礙物

並列摘要

The purpose of the study is to investigate thermosolutal convection due to the combined temperature and concentration gradients in an square enclosure. The enclosure consists of adiabatic horizontal wall and differentially heated vertical walls, but it also contains an obstacle block at different locations .The aim of the study is to delineate the effect of such a block and inclination angle on the flow fields.
In order to visualize the flow, the shadowgraph technique is used. Electrical measurements will be used to obtain mass transfer rates and to infer a Sherwood number.
To understand the flow structure, the temperature distribution and concentration distribution are investigated. Finally, the correlations between Sherwood number and solutal concentration Grashof number and thermal Grashof number are also needed to be analyzed.

並列關鍵字

enclosure ； thermosolutal ； obstacle

參考文獻

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