弯管扭转切换区流场分析

PREDICTION OF FLOW FIELDS AT TRANSITION AREA BETWEEN TWIST PIPES

当前对于单段弯管内部流场的演变与发展情况已有众多研究结果 ,可是对于多段弯管组合下的流动情况分析并不多 ,特别是对于多段不同弯曲半径的弯管组合 ,其管段间过渡区域的流动体现了不同Dean数流动的组合 ,对于Dean数占主导地位的二次流动而言该数的变动对整个流动都会产生较大的影响 .本文使用数值计算的方法分析了弯管特殊组合形式下管段过渡区域的流场演变情况 ,并分析了不同边界条件下该区域流场变动对内部流体微团运动可能产生的影响 .结果显示 ,使用不同曲率的弯管进行组合 ,产生的流场对截面上的物质运动促进作用最明显 .

Numerical modeling was performed to investigate the mixing effects of flow in pipes consisting of bends with same or different curvatures. The mixing at the transition area between different bends will cause disturbance in fluid flow. Flow rate (case change of Reynolds number) and curvatures of the bends (case change of Dean number) will take different effects in the development of secondary flow. The results show that a change in Dean number created in varying curvature bends cause significant influence on the flow.