论文部分内容阅读
基于管内核心流强化传热的概念,在管内层流充分发展段的核心流内分层填充多孔介质,并建立流动与传热的数学模型。数值模拟结果表明:与光管相比,填充金属多孔介质后,管内核心流的温度更均匀,而边界流的温度梯度更大,全场平均协同角低于36o,壁面与流体之间的换热显著增强;此外,对于提出的两种型式的强化传热管,为提高其性能评价准则值,宜在速度较高的管内核心流内填充孔隙率相对较低,而在速度梯度较大的核心流内填充孔隙率相对较高的多孔材料。
Based on the concept of enhanced heat transfer in the core flow in the tube, the porous media is layered in the core flow of the fully developed laminar flow and the mathematical model of flow and heat transfer is established. The numerical simulation results show that the temperature of the core flow in the tube is more uniform than that of the light pipe when the metal porous medium is filled, while the temperature gradient of the boundary flow is larger. The average synergy angle of the whole field is less than 36 °. In addition, for the proposed two types of enhanced heat transfer tubes, in order to improve the performance evaluation criteria, it is appropriate to fill the core flow with relatively high velocity in the relatively low porosity, while in the larger velocity gradient The core stream is filled with a porous material of relatively high porosity.