航空管壳式换热器在振动耐久性仿真中刚度等效方法研究

Research on Stiffness Equivalent Method of Shell and Tube Heat Exchanger in Vibration Durability Simulation

管壳式散热器为振动故障易发系列产品之一,振动耐久性仿真技术是分析、解决该产品故障问题的有效手段。由于管壳式散热器通常包含数百乃至上千根散热管,如果直接采用原模型进行模拟,将产生近千万的网格和大量接触,计算规模巨大,计算机硬件要求极高,且前处理工作繁杂,效率低下。这些问题严重制约了散热器整体仿真分析的有效开展。本文通过对管壳式散热器芯体刚度等效进行研究,提出了在仿真分析中的芯体刚度等效方法,并推导得出了芯体等效参数的计算公式,然后通过验证,芯体等效后的固有频率与原芯体最大误差在5%以内,且模态振型与原芯体振型基本吻合,而在仿真计算和前处理工作效率方面,芯体等效后比等效前分别提高了8倍和9倍。

Shell-and-tube radiators are one of a series of products prone to vibration failures.Vibration durability simulation technology is an effective means to analyze and solve the failure problems of this product.Because shell-and-tube radiators usually contain hundreds or even thousands of heat dissipation tubes,if the original model is directly used for simulation,nearly ten million grids and a large number of contacts will be generated,the calculation scale is huge,the computer hardware requirements are extremely high,and the pretreatment work is complicated and the efficiency is low.These problems seriously restrict the effective development of the overall simulation analysis of the radiator.In this paper,through the research on the core stiffness equivalence of shell-and-tube radiator,the core stiffness equivalence method in simulation analysis is proposed,and the calculation formula of core equivalent parameters is derived.Then,through verification,the maximum error between the natural frequency after core equivalence and the original core is within 5%,and the modal shape is basically consistent with the original core shape.In terms of simulation calculation and pretreatment work efficiency,the core after equivalence is increased by 8 times and 9 times respectively.