摘要
流体流经弯曲通道在其截面上会产生二次流现象,而黏弹性流体和牛顿流体有着不同的流动特性,流体的黏弹性对弯管内二次流能起到强化作用。为了探究黏弹性流体对弯管内二次流的影响因素,课题组采用FLUENT软件对弯曲通道中黏弹性流体的二次流特性进行数值模拟,流体的黏弹性通过UDF来实现;研究了魏森贝格数Wi、溶质黏度比β以及管道的几何结构对黏弹性流体二次流强度的影响。模拟结果表明:Wi数对弯道中的二次流强度存在非单调关系;流体的黏性越大,管内主流速度越大,从而加强管道内二次流效应;通道的几何结构如曲率比、弯道的个数对二次流都有较大的影响,曲率比越大,管内二次流越强。弯管内二次流的研究,对工程中利用弯管来加强对流和换热有一定参考意义。
Fluid flowing through a curved channel will produce a secondary flow phenomenon on its cross-section.Viscoelastic fluid and Newtonian fluid have different flow characteristics.The viscoelasticity of the fluid can strengthen the secondary flow in the bend pipe.In order to explore the influence factors of the viscoelastic fluid on the secondary flow in the bend pipe,the FLUENT software was used to numerically simulate the secondary flow characteristics of the viscoelastic fluid in the bend pipe,and the viscoelasticity of the fluid was realized by UDF.The effects of Weisenberg number Wi,solute viscosity ratioβ,and pipe geometry on the strength of the secondary flow of viscoelastic fluid were studied.The simulation results show that there is a non-monotonic relationship between the Wi number and the intensity of the secondary flow in the pipe.The greater the viscoelasticity of the fluid,the greater the velocity of the main flow in the pipe,thereby enhancing the secondary flow effect in the pipe.The geometric structure of the channel such as the curvature ratio and the number of bends have a greater impact on the secondary flow.The greater the curvature ratio,the stronger the secondary flow in the pipe.The study of secondary flow in bend pipe has certain reference significance for strengthening convection and heat transfer by using bend pipe in engineering.
作者
刘唐京
王企鲲
邹赫
LIU Tangjing;WANG Qikun;ZOU He(School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)
出处
《轻工机械》
CAS
2022年第1期1-6,18,共7页
Light Industry Machinery
基金
教育部博士点基金资助项目(20113120120003)。