螺旋翅片管防磨和防积灰特性的试验研究

应用三维颗粒动态分析仪（PDA）对气固两相流绕流螺旋翅片管进行了防磨和防积灰的实验研究。实验结果表明在翅片之间，固相颗粒密度和主流速度呈抛物线规律分布。颗粒密度和速度的这种分布规律降低了固体颗粒对翅片壁面的撞击能量，从而减轻了翅片和基管的磨损。随着来流速度和来流密度的提高，迎风面区域磨损加剧，其他区域基本不受影响。实验数据还表明，螺旋翅片的导流作用使得迎风面的滞点处产生一个轴向速度，这和光管有着本质的区别。此速度的存在有利于减轻积灰。

Experimental Study on Anti-abrasion and Anti-ash-deposition Property of Spirally Finned Tubes

An experimental study on anti-abrasion and anti-ash-deposition property of spirally finned tubes,in a solid-gas two phase flow,was undertaken with the help of a three dimensional dynamic analyzer(PDA).Test results show that,between adjacent fins,the distribution of particle concentration and of the main stream flow are of parabolic shape,whereby the impact energy of the solid particles hitting the fins is being reduced and thus the abrasion of the fins,and also that of the mother tube walls alleviated.The abrasion of windward zones intensifies with increasing incident velocity and the fluid's density,while the remaining parts are basically unaffected.Test results moreover indicate that an axial flow velocity is formed at windward stagnant points,due to the guiding effect of the spirally wound fins;in fundamental contrast to the property of bare tubes.This velocity also helps to diminish ash deposition.Figs 5,table 1 and refs 4.