两种不同入口形式的旋风分离器内流动分布的对比研究

Study on Gas Flow in Tangential Inlet and Spiral Inlet Cyclone Separator

采用试验测量与数值模拟相结合的方法对直切式和蜗壳式旋风分离器内气相流动的三维流场进行了对比研究。雷诺应力湍流模型对流场的计算结果与五孔球探针的测量结果基本相符。研究结果表明:蜗壳式与直切式分离器内的流场均呈现非对称性,涡壳式分离器内的流场相对较对称;蜗壳式和直切式分离器入口环形空间顶部的滞留层厚度分别为4mm和10mm,蜗壳式分离器环形空间最大速度出现在180°附近,直切式在45°附近。蜗壳式进口更适宜造旋,分离空间内切向速度比直切式大,气流旋转强度高。直切式分离器的排尘口处旋转气流的摆动幅度更大,容易产生返混夹带,从而影响分离效率。

The numerical simulation and experimental measurement of the gas flow is presented by CFD technique to characterize the performance of two type of cyclones with the tangential inlet and spiral inlet. The simulation result based on the Reynolds stress model is in good agreement with the measured result probed by the five orifice pilot tube. The gas flow filed is asymmetric both in tangential inlet and spiral inlet separator, the relative symmetry in spiral inlet separator is good. Compared with flow in the tangential inlet separator, the laminar flow in annular space of spiral inlet separator is smaller, the thickness of laminar in tangential inlet separator and spiral inlet separator is 10mm and 4 mm respectively ,and the maximum velocity in annular section of tangential inlet separator apparent at 45°, spiral inlet separator at 180°. The tangential velocity is bigger in spiral inlet separator than that in the tangential separator.