基于Simscape物理仿真的发动机热管理系统及控制特性研究

Research on engine thermal management system and control characteristics based on Simscape physical simulation

文章基于Simscape一维物理仿真软件,使用热流体模型和热力模型分别模拟冷却液的流动和热量的传递,开发一套包括散热器、离心水泵、蓄液罐和发动机管段传热模块的发动机热管理系统仿真模型。通过修改模块代码,将单根传热管道模块改编成多管段的管带式散热器模块和发动机管段传热模块。与实验数据对比验证,模型的散热器传热系数和发动机出口水温的最大误差均不超过10%。在此模型基础上,建立水泵挡位控制和散热器风扇启停调节系统,使发动机出口温度在发动机发热量阶跃变化的情况下,上下波动不超过2 K。该研究为热管理系统一维物理仿真和控制策略研究提供了新方法。

Based on Simscape one-dimensional physical simulation software,this paper developed a simulation model of engine thermal management system,including radiator,centrifugal pump,liquid storage tank and heat transfer module in engine pipe section,using thermal fluid model and thermal model to simulate coolant flow and heat transfer respectively.The mass energy conservation and heat transfer equations of the thermal fluid pipeline module were modified through the source code and adapted into the belt radiator module and the heat transfer module in engine pipe section.Compared with experimental data,the maximum error of the model is verified to be less than 10%in terms of radiator heat transfer coefficient and engine outlet water temperature.On the basis of this model,a pump gear control system and a radiator fan start-stop regulation system were established to make the engine outlet temperature fluctuate less than 2 K under the step change of engine heat.It provides a new method for the research on one-dimensional physical simulation and control strategy of thermal management system.