本文主要以數值模擬方式探討無因次加熱段長度、冷卻段中心位置距水平段之無因次高度與迴路寬高比等幾何參數對內含懸浮相變化微粒之矩型熱虹迴路熱傳特性影響。迴路係由加熱段、冷卻段及其間隔之絕熱段所組成；下方水平段置有一均勻等熱通量 之加熱段，其長度為 ，而於迴路右方垂直段的上方置有一等溫 冷卻段，其長度為 。數值模擬所考慮相關參數及其範圍為：PCM 微粒體積濃度 、修正萊利數 、修正次冷參數 、修正史蒂芬數 、管壁熱傳導係數比 、無因次管壁厚度 、迴路寬高比 、無因次加熱段長度 及冷卻段中心位置距水平段之無因次高度 。數值結果顯示考慮以上三個幾何參數其中以改變加熱段長度對內含懸浮相變化微粒之矩型熱虹迴路熱傳特性有顯著的影響。

This study aims, via numerical simulations, to investigate the effects of geometric parameters, including the length of heated section, the mean relative elevation of the cooled section, and the aspect ratio of the loop, on the heat transfer characteristics of phase-change-material (PCM) suspensions in a rectangular loop of thermosyphon. The loop is composed of a heated section, a cooled section, and two adiabatic sections between them. The loop is heated uniformly by a constant heat flux over the length of the bottom horizontal leg and cooled isothermally over the length of the upper portion of the right vertical leg at a constant temperature . Numerical simulations have been undertaken for the pertinent dimensionless parameters in the ranges as follows：volumetric fraction of PCM particles , the modified Rayleigh number , the modified subcooling factor , the modified Stefan number , the thermal conductivity ratio of wall to the suspending fluid , the dimensionless wall thickness , the aspect ratio of rectangular loop , the dimensionless length of heated section and the dimensionless mean relative elevation of the cooled section to the bottom horizontal leg . Among the three geometric parameters considered, numerical results clearly indicate that variation of the length of the heated section can exert significant effects on the heat transfer characteristics of PCM suspensions in a rectangular loop of thermosyphon.

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