真空喷射射流流场的Fluent模拟分析

为了对真空射流流场进行研究,应用Fluent软件并基于VOF(volume of fluid)方法、k-ε标准湍模型及PISO算法,对不同喷口直径及入射压力的直射式锥型流道喷嘴的射流流场速度和湍流运动分布进行了数值模拟分析.结果表明:1)入口压力相同,喷嘴直径越大,射流与周围介质间的速度梯度越大,可促进射流的扩散和液滴破碎后的尺寸均匀分布;2)喷嘴直径一定,入口压力在10~15 MPa内,射流湍流强度分布达到最佳状态,射流流场较好;3)如果不考虑材料的溶解性,相对于三氯甲烷和四氯化碳,丙酮作为溶剂时的液体喷射雾化效果较好,适于制备质量较好的高分子薄膜.

Numerical Simulation of the Vacuum Spray Jet Flow Based on Fluent Analysis

This paper investigated the velocity and turbulence distribution of the cone nozzle jet flow field spraying into a vacuum chamber under different nozzle diameters and injection pressures.The simulations were carried out by using the Fluent software based on the volume of fluid method,the standard k-ε turbulence model and the PISO(pressure implicit with splitting of operators) arithmetic.The results show that the jet flow and velocity gradient increase with increasing nozzle diameter,and it is helpful to improve jet spray quality with size uniform distribution after jet diffusion and drop breakup.When the nozzle diameter is constant,the jet turbulence intensity distribution achieves the optimum condition within 10～15 MPa,and the flow field is better than that under any other pressures.Compared with chloroform and carbon tetrachloride solvents,acetone shows better flow distribution and atmospheric effect if neglecting the solubility of the polymer materials.