一种混沌C型几何流动混合耦合电磁热特性数值分析

Numerical analysis of mixed characteristics of chaotic C-type geometric flows coupling electromagnetic thermal characteristics

为克服传统管式反应器混合效率差和传统加热方式传热速率低而导致的反应器性能限制,本文提出了一种基于混沌对流强化的管式微波反应器,即采用混沌C型几何管道,通过COMSOL软件对流体混合过程和微波加热过程分别进行多物理仿真模拟,探究低雷诺数(Re)下流体混合特性和电磁热特性。分析得出:当Re≥15时,混沌C型管道内出现明显混沌流动,通过增加雷诺数可以提高涡流强度,以促进均匀混合;混沌C型几何周期数的增加会产生更多的扰动数,不断改变流体运动方向,从而提高传热性能;混沌管道内电场分布较平面管道更复杂,微波能量利用率更高;依据雷诺数和功率分析混合和电磁热特性二者耦合的相关性,初步揭示了二者耦合机理。

In order to overcome the reactor performance limitations caused by the poor mixing efficiency of traditional tubular reactors and the low heat transfer rate of traditional heating methods,a tubular microwave reactor using the chaotic C-type geometric pipe was proposed.The mixing and electromagnetic thermal characteristics of fluid at low Reynolds number(Re)were simulated by COMSOL software,respectively.The results were as follows:When Re≥15,chaotic flow appeared obviously in chaotic C-type pipe,and eddy current intensity could be increased by increasing Reynolds number to promote uniform mixing;The increase of chaotic C-type period number would produce more disturbance number and constantly change the direction of fluid movement,thus improving the heat transfer performance;The electric field distribution in chaotic pipe was more complex than that in planar pipe,and the microwave energy utilization rate was higher;Based on Reynolds number and power analysis of the correlation between mixing and electromagnetic thermal characteristics,the coupling mechanism of the two was initially revealed.