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针对多孔夹层圆柱壳的主动散热性能以及等效热导率的计算问题,通过推导多孔结构的等效热导率和主动散热状态下的稳态温度控制方程,在对流换热条件下,计算了考虑主动散热后所折减的等效热导率,及其与结构相对密度和流体流速之间的关系。采用考虑主动散热的等效热导率,计算结构瞬态温度分布,并与有限元结果进行对比。同时,计算了夹层圆柱壳相对密度和结构散热性能的关系以及最大散热性能相对应的最优相对密度和最优杆件厚度。通过瞬态温度分布结果与有限元结果对比,得到采用考虑主动散热的等效热导率所得结果与有限元结果吻合,说明了计算等效热导率方法的有效性,并且可以准确地计算瞬态温度分布;同时分析得到等效热导率随着流体流速的增大而减小,随着结构相对密度的增大而增大;在相同结构质量下,正方形和正六边形构型具有较好的主动散热性能。
Aiming at the problem of active cooling performance and equivalent thermal conductivity of porous laminated cylindrical shell, by calculating the equivalent thermal conductivity of porous structure and the steady-state temperature control equation under active cooling condition, Consider the equivalent thermal conductivity reduced by active heat dissipation and its relation to the relative density of the structure and the fluid flow rate. Taking into account the equivalent thermal conductivity of active cooling, the transient temperature distribution of the structure is calculated and compared with the finite element results. At the same time, the relationship between the relative density of the mezzanine cylindrical shell and the thermal performance of the structure and the optimal relative density and the optimum thickness of the rod corresponding to the maximum thermal performance were calculated. By comparing the transient temperature distribution results with the finite element results, the equivalent thermal conductivity considering active heat dissipation is obtained and the results are in good agreement with the finite element results. It shows that the method of calculating equivalent thermal conductivity is effective and can calculate the instant At the same time, the equivalent thermal conductivity decreases with the increase of the fluid velocity and increases with the increase of the relative density of the structure. Under the same structural mass, the square and regular hexagonal configurations have better thermal conductivity Good active thermal performance.