| With the continuous development of microscale systems,more and more attention has been paid to microscale heat exchange in the fields of electronic chips,and microchannel heat transfer has become a research hotspot as an effective heat exchange method in the field of microscale.In this paper,the finite volume method is used to simulate the heat flow field of microchannels under the action of finned spoiler by dynamic grid technology,and relevant conclusions are analyzed.Firstly,the microchannel model under the action of the finned spoiler is established,the ANSYS Meshing software is used for meshing,the Fluent simulation software is used to verify the mesh independence,the model is verified,and the microchannels under the action of the finned spoiler with periodic motion are numerically simulated,and the flow field and temperature field of the microchannel under different motion frequencies of the spoiler are analyzed in detail.The friction coefficient fr and the comprehensive evaluation factor PEC change periodically with the flow time,and their periods are the same as those of the spoiler.With the increase of the movement frequency of the spoiler,the comprehensive evaluation factor PEC also increased,and the PEC increased by 30% compared with the smooth microchannel under the working conditions of Re=50 and f=50Hz,indicating that the effect of the finned spoiler had a positive effect on the comprehensive heat transfer of the microchannel.Secondly,the effects of the length,number and rotation center position of finned spoilers on the flow heat transfer of microchannels were studied,and the single-factor control method was used to simulate and analyze them sequentially.The study of spoilers of different lengths found that with the increase of spoiler length,the overall heat transfer performance of microchannels gradually increased,and the heat transfer efficiency gradually increased.With the increase of the number of finned spoilers,the Nu of the microchannel increased the trend,but the friction coefficient fr changed on the contrary and showed a gradual decreasing trend,and the optimal number of spoilers in the microchannel was determined by comprehensively considering the heat transfer effect and resistance brought by the number of spoilers.In the simulation study of the three rotation center positions of the spoiler,it is found that the rotation center position of the finned spoiler has a greater influence on the resistance in the microchannel,which is mainly reflected in the change of friction coefficient fr,when the swing angle of the spoiler reaches a maximum of 60°,the flow section of the fluid in the microchannel is the smallest,and the fr also reaches the maximum value,and with the increase of the distance of the rotation center position from the starting point,the disturbance of the flow field is gradually enhanced.Finally,the shape of the microchannel is changed,and the parameters such as the number,length,and rotation center position of the spoiler with better heat exchange effect are selected,and on this basis,the flow heat transfer of the triangular ribbed microchannel and the corrugated plate microchannel is studied,and the changes of the flow field and temperature field are analyzed and compared and analyzed,and it is found that the heat transfer effect of the corrugated plate microchannel is stronger than that of the triangular rib microchannel under the same working conditions,but at the same time,the resistance of the corrugated plate microchannel is greater,and the influence of flow and heat transfer is comprehensively considered.Using the comprehensive evaluation factor PEC as the standard,the comprehensive performance of triangular ribbed microchannels was considered to be better.In this paper,the dynamic grid technology is used to realize the numerical simulation of the heat flow field of microchannels under the action of finned spoilers,and the change law of flow field and temperature field inside microchannels is obtained,which has reference and guiding significance for the subsequent research of turbulent microchannels. |
