针对复杂换热网络MINLP问题,本文应用多维函数渐变法探索和分析了连续变量和整型变量引起的网络性能非线性和非凸特性。研究表明,当系统规模增大时,不但连续变量的叠加效应将增加系统的非线性,整型变量将使得非线性特性更为严重。 Aiming at the MINLP problem of complex heat exchange networks, this paper uses the multi-dimensional function gradient method to explore and analyze the non-linear and non-convex properties of network performance caused by continuous variables and integer variables. The research shows that when the system size increases, not only the additive effect of continuous variables will increase the nonlinearity of the system, but the integer variable will make the nonlinearity more serious.