论文部分内容阅读
本文基于计算流体力学软件FLUENT采用大涡模拟方法(LES)及Smagorinsky-lilly亚格子模型,对空冷岛扁平管外翅片空间的流动与换热特性进行了三维瞬态湍流数值模拟。计算结果表明大涡模拟方法能较好地模拟空冷岛扁平管外翅片空间的瞬态流动特性,能够捕获更多的流场细节信息。可得出流场中温度、压力、涡量等各参数的瞬态变化特性以及翅片空间尾流区瞬态三维涡的发展演化过程,更好地预测多尺度湍流。为进一步揭示扁平管温度场和流场的协同关系以及大型空冷系统多尺度输运规律和非线性尺度效应机理打下基础。
Based on LES and Smagorinsky-Lilly sub-lattice models, FLUENT (Computational Fluid Dynamics) software is used to simulate the three-dimensional transient turbulent flow and heat transfer characteristics of the outer fin space of the flat tube. The results show that the large eddy simulation method can simulate the transient flow characteristics of the outer fin space of the flat tube of air-cooled island and capture more detailed information of the flow field. The transient characteristics of temperature, pressure and vorticity in the flow field and the evolution and evolution of the transient three-dimensional vortex in the wakespace of the fin space can be obtained and the multi-scale turbulence can be predicted better. It lays the foundation for further revealing the synergic relationship between the temperature field and the flow field of the flat tube and the multi-scale transport law and the nonlinear scale effect mechanism of the large-scale air-cooling system.