Modeling And Simulation Of Vehicle Thermal Management System

Vehicle thermal management system include: engine cooling system, lubricationsystem, intake and exhaust system, air-conditioning system and other thermo flow systemsin the vehicle. The performance of the vehicle thermal management system may affect thevehicle dynamic performance, fuel economy performance and ride comfort performance.This thesis focuses on automotive air-conditioning system and engine cooling systemin the vehicle thermal management system. The working of the air-conditioning systemand cooling system are introduced at first, then, an Automotive Air-Conditioning Modelicamodel library and an Engine Cooling Modelica model library are established based onModelica programming language. These two libraries are used in a vehicle thermalmanagement system simulation together with a Powertrain Modelica model library, inorder to study the coupling relationship among engine cooling system, automotiveair-conditioning system and powertrain system.The article reviews both of domestic and foreign research status of automotiveair-conditioning simulation, cooling system simulation and vehicle thermal managementsystem simulation. And then a new refrigerant thermodynamic calculation model and anovel one-dimensional discrete heat exchanger model for air conditioning system areproposed based on Modelica. These new refrigerant model and heat exchanger model areused to set up a complete Automotive Air-Conditioning Modelica model library includingevaporator, condenser, compressor, thermostatic expansion valve, cabin and othercomponent models. Some of the key component models in the model library are validatedby experimental data. Similarly, an Engine Cooling Modelica model library includingengine, radiator, water pump, thermostat and other componet models is built, and partlyvalidated. Finally, a vehicle thermal management system model including the two thermoflow system and the powertrain system is established. Then a simulation underECE_EUDC_Low condition is taken, and some conclusions about the couplingrelationship among these sub-systems in the thermal management system are givenaccording to the simulation results.