金属丝网强化余热回收烟气换热器的试验与数值研究

Experimental and Numerical Research on Metal Wire Mesh Enhanced Waste Heat Recovery Exhaust Heat

为探究金属丝网强化元件在余热回收烟气换热器中的应用可行性及其性能表现,对嵌有金属丝网的通道的流动与换热性能开展试验与数值研究。对嵌入不同孔隙率金属丝网的通道进行了试验研究,基于FLUENT软件进行了模拟计算和流场分析,并分析了丝网高度对流动和传热性能的影响。结果表明,相比于传统平直翅片,嵌入金属丝网后通道综合性能指标最大提高58%。综合性能随孔隙率的提高先增后减,0.945为最佳孔隙率。同时,使用高度与流道高度一致的金属丝网,可以获得最佳综合性能。在相同压力损失下,金属丝网通过均匀流体温度、破坏边界层可以比平直翅片通过增加传热面积获得更好的综合性能,证明了金属丝网作为烟气换热器强化元件的可行性。

In order to explore the feasibility and performance of metal wire mesh reinforcement elements in waste heat recovery exhaust heat exchangers,experimental and numerical studies on the flow and heat transfer performance of channels embedded with metal wire mesh were conducted.Experimental research was conducted on channels embedded with metal wire mesh with different porosities.Simulation calculations and flow field analysis were conducted based on FLUENT,and the influence of wire mesh height on flow and heat transfer performance was analyzed.The results show that compared to traditional flat fins,the comprehensive performance index of the channel after embedding the metal wire mesh is improved by a maximum of 58%.The comprehensive performance first increases and then decreases with the increase of porosity,with 0.945 being the optimal porosity.At the same time,using a metal wire mesh that is consistent with the height of the flow channel can achieve the best comprehensive performance.Under the same pressure loss,the metal wire mesh can achieve better comprehensive performance by uniform fluid temperature and breaking the boundary layer compared to flat fins by increasing heat transfer area,which proves the feasibility of using the metal wire mesh as a strengthening element for exhaust heat exchangers.