纵向涡产生器几何形貌与纵向涡特性及对流换热关系研究

Seeking effective means of heat transfer enhancement has an extremely signifigance which is one of the important research directions of the energy saving and emsissions reducing technologies. Introducing longitudinal vortex generators on the heat transfer surface is an effective heat transfer enhancement method.The heat transfer is enhanced by using the longitudinal vortex generators, and the flow resistance increases observably at the same time. To enchance heat transfer and decrease the flow resistance becomes a very urgent and important task, still there is extremely necessary to make great effort on this problem, althought it has been studying for a long time and put into many researchers' efforts. If the structure of the longitudinal vortex generator that can enhance heat transfer greatly but without causing a substantial increase of the flow resistance could be discovered, heat transfer enhancement capacity would be further improved. It’s very necessary to further reveal the relationship between the structure of the longitudinal vortex generator and vortices intensity, vortices attenuation, heat transfer characteristic and flow resistance characteristic on the basis of existing studies. In this project, coupling the vortex generators geometry and attack angle into vortex generators morphology parameters for the idea to carry out two studies, the numerical simulation and experimental methods are used: to establish the descriptive procedure of the vortex generators morphology parameters which can determine the longitudinal vortices characteristics, the heat transfer and the flow resistance characteristics generated in the heat transfer channels; to seek the influence of the vortex generators morphology parameters on vortices intensity, vortices attenuation, heat transfer characteristic and flow resistance characteristic. The goal of this project is to reveal the relationship between the geometrical structure of longitudianl vortex generators and their longitudinal vortices characteristics. The results of this project will have great importance not only on providing deep insight on the longitudinal vortices characteristics and its heat transfer enhancement mechanism, but also on providing a theoretical basis and the underlying data on optimizing the the geometrical structure of longitudianl vortex generators, thereby this project has high academic value and broad application prospects.

寻求强化传热的有效手段是节能减排，提高能源利用率的重要研究方向之一，具有重要的意义。在换热表面设置纵向涡产生器是一种有效的强化传热措施。如果找到能够显著增强传热而不引起阻力大幅度增加的纵向涡产生器结构,可进一步提高强化传热能力。从而在现有研究基础上，进一步揭示纵向涡产生器结构与涡强度、涡衰减、传热特性及阻力特性的关系非常必要。项目以把涡产生器的几何形状和攻击角耦合成涡产生器形貌参数为思路，采用数值分析和实验相结合的方法开展两方面研究:（1）建立决定纵向涡特征、传热性能及压力损失性能的涡产生器形貌描述方法；（2）寻求涡产生器形貌参数对涡特征、传热性能及压力损失性能影响规律。目标在于揭示纵向涡产生器几何形貌与其所产生纵向涡特征的关系。项目结果可增进对纵向涡特征及其强化传热机理的认识，还可为优化纵向涡发生器几何形貌提供了理论依据和基础数据，具有较高的学术价值和较广泛的应用前景。

寻求强化传热的有效手段是节能减排，提高能源利用率的重要研究方向之一，具有重要的意义。在换热表面设置纵向涡产生器是一种有效的强化传热措施。如果找到能够显著增强传热而不引起阻力大幅度增加的纵向涡产生器结构,可进一步提高强化传热能力。从而在现有研究基础上，进一步揭示纵向涡产生器结构与涡强度、涡衰减、传热特性及阻力特性的关系非常必要。项目以把涡产生器的几何形状和攻击角耦合成涡产生器形貌参数为思路，采用数值分析和实验相结合的方法开展两方面研究:（1）建立决定纵向涡特征、传热性能及压力损失性能的涡产生器形貌描述方法；（2）寻求涡产生器形貌参数对涡特征、传热性能及压力损失性能影响规律。通过深入细致研究获得的主要学术进展是：获得了涡产生器的几何形状因子Sf，实验研究了不同工况下带涡产生器的圆管管翅式换热器流动与传热特性，获得了形状因子Sf与传热性能及阻力特性有关的经验关联式。获得了换热通道二次流强度无量纲数Se和Nu的分布，揭示了纵向涡产生器几何形貌与其所产生纵向涡特征的关系。项目研究结果不仅可以增进对纵向涡特征及其强化传热机理的认识，还可为优化纵向涡发生器几何形貌提供了理论依据和基础数据。