电热驱动Bimorph微执行器对流系数估算方法研究

摘要

A method of estimating the convection coefficient at microscale is presented in this paper,based on the modeling and experimental data of a microfabricated electrothermal bimorph actuator. In this method,an analytical heat transfer model of the electro-thermal bimorph actuator is established first. Then the model is used to analyze the temperature distribution and extract the convection coefficient from measurement data. The convection coefficient obtained by this method matches the experimental result within 8.1%,which validates the rationality of this method.%随着电热驱动MEMS器件尺寸进一步缩小，传统热对流系数的取值已无法满足微系统分析建模需求。针对电热型Bimorph结构的MEMS微镜驱动器，通过分析其温度分布，并以其平均温度为参考指标建立简单热阻和对流热阻分段模型，推算出微尺度下精确的对流系数，提高了微执行器设计模型的驱动性能。经理论计算和实验测试验证，对流系数值的误差在8.1%以内，满足实际设计需求，验证了该方法的合理性和可行性。