A novel swirl jet nozzle for spray cooling tower was proposed and designed,numerical simulation of two-phase flow inside the nozzle was carried out by Fluent,and flow rate of inlet water and injected air with different inlet pressures were measured experimentally.A good agreement was obtained between experimental data and simulation results,the maximum relative error was less than 10％,thus correctness of numerical simulation was verified.Subsequently,simulation results of internal flow field of the nozzle with different structural parameters were obtained by this method,the effects of spiral angle of twisted tape,diameter and length of mixing tube and length of diffusion tube on air jet performance and flow characteristic of the nozzle were investigated and structural optimization of the nozzle was obtained.The simulation results show that,in order to obtain the best jet performance and ensure a large outlet speed,the optimum range of spiral angle locates between 35° and 45°,the diameter of mixing tube is 2.5 to 3 times of throat diameter (d),the length of mixing tube is 4.5 to 7 times of d and the length of diffusion tube is 1.5 to 4.5 times of d.%提出并设计了一种应用于喷雾冷却塔的新型旋流引射喷嘴,利用Fluent软件对喷嘴内部流场进行两相流数值模拟,并实验测量了不同压力下的进水流量和引射空气流量,实验数据与模拟结果具有较高的吻合度,最大相对误差低于10％,验证了数值模拟的准确性.随后利用该方法得到了不同结构参数下喷嘴内部流场的仿真值,重点研究了旋流片螺旋升角、混合管直径和长度以及扩散管长度对喷嘴空气引射性能与流动特性的影响规律,从而对喷嘴结构进行优化.模拟结果表明:为使喷嘴取得最佳的引射性能,同时保证较大的出口速度,旋流片螺旋升角的最优取值范围为35°-45 °,混合管直径为2.5-3倍喉嘴直径d,混合管长度为(4.5-7)d,扩散管长度为(1.5-4.5)d.
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