铁路客车空调负荷的非稳态计算方法研究

Research on Unsteady Calculating Method for Train Air-conditioning Loads

采用反应系数法以非稳态传热的方式计算铁路客车空调负荷,在对列车通过围护结构传入车内的热量、通过玻璃窗进入车内的太阳辐射热量、人体散热量、室外新风带入室内的热量和照明散热量分别进行计算之后,建立了状态空间模型。进而应用状态空间法求取了车壁的反应系数,通过热平衡分析得到了得热量与空调负荷的传递函数系数值,用拉普拉斯变换法进行了验证,并编制了相应的计算机程序。研究表明,非稳态传热的计算方法能更好的反映铁路客车空调负荷形成的基本机理,有助于空调系统的精确设计、系统实时控制、能耗分析等多方面的研究,并值得地铁车辆、城市轻轨车辆借鉴。

The paper introduces the unsteady heat conduction method for calculating the loads of a passenger train by using reactive coefficient method. Statespace model was set up after calculating the heat conduction through the structure walls, the sun radiant heat conduction through the windows, the heat emitted by human beings, the heat brought into the train by fresh air and the heat emitted by lighting. Then the reactive coefficient of the train wall was obtained by applying statespace method, the transfer function values of heat and airconditioning loads were gained by heating balance analysis, validated by using Laplace transform, and the corresponding computer programs compiled. The study shows that the calculation method for unsteady conduction can reflect better the formative mechanism of the load of a passenger train, facilitating precise design of airconditioning system, real time system control, and energy consumption analysis, etc. The method can also be used for underground cars and urban rail cars.