高压低耗散新型喷嘴的设计及数值仿真研究

针对热镀锌车间内吹环喷嘴吹扫钢管内部多余锌粒时耗气量大、出口速度低、冲击力小等问题,设计一款高压低耗散的新型喷嘴,喷嘴内轮廓线采用四次B样条曲线,出口采用椭圆形设计。基于流体力学的基本方程和S-A湍流模型,建立了吹扫射流的数学模型。分析不同入口压力条件下,入射角为30°、45°、60°、90°时,射流对管壁的打击力,并研究喷嘴出口与管口距离的变化对打击力的影响。结果表明:B样条喷嘴冲击到壁面的压力、喷嘴速度和气帘宽度均大于传统的锥直形喷嘴,吹扫效果明显提高。

Design and Numerical Simulation of a New Nozzle with High Pressure and Low Dissipation

Taking the air purged nozzle in the galvanized steel pipe purging system as the research object, the mathematical model of the purge jet was established, the inner contour line was described by quartic B spline curve, and the exit of the nozzle was described by ellipse shaped section. Based on the S-A turbulence model, the Fluent software was used to simulate the slot nozzle flow field. In order to study the influence of the incident angle and purge distance on the purge flow field, the impact force at the inlet angles of 30°, 45°, 60°, and 90° under different inlet pressures was analyzed. The influence of purge distance change on the impact force was studied.The results show that the pressure hitting the wall, the jet velocity and the gas curtain width of the designed nozzle are greater than that of the traditional nozzle and the sweeping effect is improved.