【摘要】 本文基于MATLAB/Simulink仿真平台,建立了某型柴油活塞发动机冷却系统的一维仿真模型,研究了冷却系统对环境温度、气缸散热量等参数的敏感性,并分析了节温器对冷却系统敏感性及冷启动过程中动态特性的影响.结果表明,节温器对流量的分配和调节作用可以有效地增强系统对外部扰动的适应能力,使系统的工作更加稳定;对冷却系统参数的敏感性分析,可用于研究系统的工作特性,为系统的设计和运行控制提供依据;节温器的时间常数对冷却系统的动态特性影响显著,较小的时间常数有利于保证发动机的稳定工作.更多还原

【Abstract】 A one-dimensional numerical model of the diesel engine cooling system is established based on MATLAB/Simulink.The sensitivities of the cooling system to the parameters,such as the environment temperature,heat rejection rate,etc.,are investigated,and the effects of the thermostat on the sensitivities and the dynamic characteristic of the cold starting process are analyzed.The results show that the distribution and regulation function of the thermostat on the coolant flow rate can enhance the adaptability of the cooling system to the external disturbances effectively and can make the system work more stable.The sensitivity analyses of the cooling system helps us to understand the system characteristics and can be treated as a foundation of the design and control of the cooling system.The time constant of the thermostat has a great influence on the dynamic characteristic of the cooling system and a thermostat with smaller time constant is of great benefit to the working stability of the engine cooling system.更多还原