水平液固循环流化床换热器传热性能研究

Heat transfer performance of horizontal liquid-solid circulating fluidized bed heat exchanger

通过对管内插入Kenics静态混合器的水平液固循环流化床换热器进行数值模拟和实验研究,考察了静态混合器扭率对颗粒分布、传热性能和流阻性能的影响。结果表明:水平管内安装Kenics静态混合器的扭率越小,管内颗粒分布均匀距离越长。当雷诺数在10 000—45 000之间,扭率为1.5,2.5,4,6的Kenics静态混合器的综合性能评价指标PEC均大于1,说明了水平流化床换热器插入Kenics静态混合器能够改善传热。当流速大于1.5 m/s,在2 m长的水平流化床换热器内安装一个扭率为1.5的Kenics静态混合器能够达到改善颗粒分布和提高传热性能的效果。

The horizontal liquid-solid circulating fluidized bed heat exchanger with Kenics static mixer was studied by numerical simulation and experimental research. The effects of Kenics static mixer with twist rate on the particle distribution,heat transfer performance and flow resistance performance were studied by experiments and numerical simulation. The results show that the particle distribution uniform distance decreases with the increase of the Kenics static mixer with twist rate. The performance evaluation criteria of Kenics static mixer with twist rate Y = 1. 5,2. 5,4,6 are over 1 in the range of Reynolds number 10 000-45 000,which indicates that the horizontal fluidized bed heat exchanger with Kenics static mixer can enhance heat transfer. Installing a Kenics static mixer with twist rate Y =1. 5 in a 2 m-long horizontal fluidized bed heat exchanger can achieve the effects of improving particle distribution and heat transfer performance,when the velocity is more than 1. 5 m / s.