曲率对环形浅液池内热毛细-浮力对流的影响

为了了解曲率对水平温度梯度作用时环形浅液池内热毛细-浮力对流的影响,采用有限容积法进行了非稳态二维数值模拟。环形液池外壁被加热,半径为40 mm;内壁被冷却,半径分别为20和10 mm;液池内的流体为0.65cS t的硅油,其P r为6.7,液层厚度为0.5~1.5 mm。模拟结果表明,当水平温度梯度较小时,两种曲率下的流动均为稳态流动,随着温度梯度的增加,流动将会失去其稳定性,转化成各种振荡流动;流动转化的临界温差与曲率有关,模拟计算的临界温差与实验结果吻合较好。

Effect of curvature on thermocapillary-buoyancy convection in shallow annular pool

In order to understand the influence of curvature on thermocapillarybuoyancy convection in a differentially heated annular pool with the outer heated cylinder(r_o=40 mm) and the inner cooled cylinder(r_i=20 mm or 10 mm),conducted a series of unsteady twodimensional numerical simulations with the finitevolume method.The pool was filled with the 0.65cSt silicone oil(Prandtl number Pr=6.7),which depth is from 0.5 to 1.5mm.Results show that both of the flows with different curvature are stable at the small temperature difference.With the increasing of the temperature difference,the simulation can predict oscillatory flows.The critical temperature difference depends on the curvature of annulus.It is found that there is a good agreement between the simulation and experiment results on the critical temperature difference.