Abstract: The influence of rod diameter d/D and center-to-center spacing ratio S/D on the forced convective heat transfer and flow drag for two isothermal cylinders in tandem arrangement are numerically investigated using a finite volume method for the three-dimensional channel. The working fluid is the eutectic alloy GaInSn. The convective heat transfer is much stronger as rod diameter decreases and as center-to-center spacing ratio increases. The overall increment of heat transfer decreases with the increase of center-to-center spacing ratio and rod diameter. Moreover, the overall increment of heat transfer fluctuates when the center-to-center spacing ratio is less than the critical value S/D=4. The overall increment of heat transfer is 22.3%—25%, and the system drag (including the rod and cylinder drags) is reduced by 40% at d/D = 0.1 and S/D≥5, indicating that the utilization of small rod to disturb the fluid can enhance the heat transfer and reduce the drag.

Key words: rod, heat transfer, overall increment of heat transfer, flow, drag, convection

摘要： 以圆柱上游布置扰动体的双钝体绕流模式为研究对象，通过有限体积法数值研究了Reynolds数Re=1000时钝体直径比（d/D）、间隙率（S/D）对双钝体系统传热性能和系统阻力的影响规律。结果表明，小直径扰钝体对系统的对流换热更为有利，且系统的对流换热随间隙率的增大而递增。以等直径双钝体（d/D=1）系统为基准，总换热增长量（HI）随间隙率和扰动体直径的增大而减小，且间隙率小于临界值（S/D=4）时换热增长量波动比较明显。当d/D=0.1，S/D≥5时，系统的换热增长量为22.3%～25%，且此时系统的流动阻力可减小约40%，这表明上游小直径扰动体的利用在增强系统换热性能的同时也减小了系统的阻力。

关键词: 扰动体, 换热, 换热增长量, 流动, 阻力, 对流