基于Matlab的板式换热器动态特性建模与仿真

为了正确预测板式换热器的动态特性，在合理假设的基础上，根据流道和换热平板的质量、能量守恒方程，建立了无量纲动态仿真数学模型。考虑了流体沿流动方向的导热扩散特性、换热平板的金属蓄热以及沿径向的导热对出口温度瞬态响应的影响。基于Matlab的数值计算基础，对无量纲动态仿真数学模型的空间维变量的一阶导数项采用向后差分，二阶导数项采用中心差分，然后采用Matlab的ODE求解器进行求解，得到了阶跃扰动和频率扰动下的出口温度的响应曲线。

Dynamic Properties Modelling and Simulation of Plate Heat Exchanger Based on Matlab

In order to predict the dynamic properties of plate heat exchanger correctly,the dimensionless dynamic simulation mathematic modelling is established based on the reasonable hypothesis and according to mass and energy equation of the fluid passes and heat exchange plate.The influence of the heat conduction dispersion,heat storage and heat conduction of the heat plate in the longitudinal direction on the exit temperature's transient response is taken into account.Based on the numerical computation of Matlab,taking the backward difference to the first order space dimension of dimensionless dynamic simulation mathematic model and central difference to the second order,then using the ODE solver of Matlab,the response chart of exit temperature at the disturbance of step and frequency is obtained.