板式换热器流动与传热特性的数值研究

Numerical study on flow and heat transfer characteristics of a plate heat exchanger

建构了与BR0.015F型人字形波纹板式换热器实际结构、尺寸完全相同的冷热双流道物理模型,采用Fluent软件开展了数值仿真,通过改变该换热器的波纹节高比l/h、波纹倾斜角β和流道内流体流动形态,分析了其流动和传热特性,明晰了板片结构参数的变化对流动和传热特性的影响,最终获得了压降与换热最佳时的结构参数.结果表明:板式换热器的l/h越小时,其换热越好且流阻越小,l/h=2.4时的换热效果最佳且流阻最小;随着β的增大,其换热效果增强,但其流阻亦增大,β=45°时的同功耗换热效果最佳;单边流的流动与传热特性均优于对角流.

A cold＆amp;hot dual-fluid-channel physical model whose geometry and sizes are completely the same as those of a real BR0 .015 F-type herringbone corrugated plate heat exchanger was set up and numerical simulation was carried out based on Fluent Software .The flow and heat transfer characteristics of the exchanger was analyzed after changing its ratio l/h of normal corrugated pitch to corrugated height ,corrugated inclination angle βand fluid flow pattern in the fluid channel , the effects of variation of plate geometric parameters on its flow and heat transfer characteristics were known and the geometric parameters that have the optimal effect of pressure drop as well as heat transfer were obtained .The result shows that the smaller the l/h of the plate heat exchanger ,the stronger the heat transfer effect as well as the smaller the flow resistance and the heat transfer effect is strongest as well as the flow resistance is smallest at l /h=2.4;the heat transfer effect enhances as well as the flow resistance increases by increasing βand the heat transfer effect is best with the same power consumption at β=45＆#176;;both flow and heat transfer characteristics of a single-side flow are superior to those of a diagonal flow .