翅片参数对小型转子发动机端盖传热特性影响

The Influence of Fin Parameters on the Heat Transfer Characteristics of the End Cover of a Small Rotary Engine

为了探究小型风冷转子发动机散热翅片参数与端盖传热特性之间的关系。基于流体力学理论与传热学理论,建立了整机冷却散热的流固耦合三维仿真模型,对具有不同散热翅片参数的发动机进行了数值模拟,研究了翅片的高度、长度、厚度及翅片间隙对端盖表面的换热能力和综合性能的影响。结果表明,随着翅片高度的增加,端盖表面的换热能力先提高后降低,但综合性能评价指标不断减小。翅片长度小于10mm时,适当的增加翅片长度可提高换热能力。此外,随着翅片间隙与翅片厚度的增加,端盖表面的散热能力持续增强、综合评价指标不断提高。该研究可为小型风冷转子发动机端盖散热翅片的优化设计提供理论支持。

To investigate the relationship between the fin parameters and the heat transfer characteristics of the end cover for a small air-cooled rotary engine.Based on the theory of fluid mechanics and heat transfer,a three-dimensional fluid-solid cou-pling simulation model of the cooling and heat dissipation for the whole machine was established,and numerical simulations were conducted for engines with different fin parameters to study the effects of fin height,length,thickness and fin spacing on the heat transfer capacity and comprehensive performance of the end cover surface.The results show that with the increase of fin height,the heat transfer capacity of the end cover surface first increases and then decreases,but the comprehensive performance evaluation index keeps decreasing.When the fin length is less than 10mm,increasing the fin length appropriately could improve the heat transfer capacity of the end cover surface.In addition,with the increase of fin spacing and fin thickness,the heat dissipa-tion capacity and the comprehensive evaluation index of the end cover surface are continuously improved.This study could provide theoretical support for the end cover fins optimal design of small air-cooled rotor engines.