混水角对强迫对流混水过程影响的熵产数值分析

Numerical analysis of entropy production about the effect of mixwater angle on forced convection mixwater process

以两入口流速相同情况下强迫对流混水过程这一物理问题为研究对象,采用计算流体力学、数值传热学理论进行数值计算,分析讨论了对流混水角在30°、45°、60°、90°条件下速度、温度、熵产的分布以及变化关系。计算、分析结果表明:熵产主要分布在两根进水管的交汇区域,及混水后的出水管区域,最大值发生在混水交点处,而两进口支管区域熵产较小;粘性熵产中壁面熵产平均值占粘性熵产总和平均值的98.22%,传热熵产中壁面熵产平均值占传热熵产总和平均值的99.23%。在熵产中"壁面熵产"占绝对比重,内部熵产可忽略。不可逆传热熵产占熵产比重较大,混水角度90°熵产最小,最优混水角度为90°。

With physical problems about forced convection mix-water process as the research object when two inlet have the same velocity,the paper used computational fluid dynamics and numerical heat transfer theory to carry on numerical calculation,analyzed and discussed the entropy production speed,temperature,the distribution and variation relationship when convection mix-water angle was at 30°,45°,60°and 90°.The results showed that the entropy production mainly distributed in the intersection of two inlet pipes junction area and the outlet pipes area after water mixed,the maximum occurred in mix-water intersection place,but two import tubes regional entropy production was smaller;the average of wall entropy production got 98.22% of the sum sticky entropy production in the sticky entropy,and the average of wall entropy production got 99.23% of the sum heat transfer entropy production in the heat transfer of entropy production.In entropy production the ＂wall of entropy production＂ accounted for absolute proportion,internal entropy production can be ignored.The irreversible heat transfer entropy production took greater proportion of the entropy production,the entropy production was smallest when the mix-water angle was at 90 °,so the optimal mix-water angle was at 90 °.