混合制冷工质临界参数的最优化算法

An optimization algorithm for calculating the critical parameters of multicomponent mixture refrigerants

为了计算混合制冷工质的真实临界参数,采用热力系统平衡稳定性的Helmholtz自由能判据,建立了多元混合工质临界参数的热力学计算模型,提出了求解混合工质真实临界参数的非线性控制方程组的具有约束条件的最优化算法。经过对一些混合工质临界参数的实例计算结果与文献报导的实测数据的对比分析表明,该算法具有稳定收敛、预测精度较高的优点。当采用混合物中各纯组份的临界参数的线性组合来赋初值时,该算法具有很快的计算速度和较好的精度,完全可以满足工程实际计算、筛选及研发新混合工质的需要。

Aiming to calculate the true critical parameters of refrigerant mixtures, the Helmholtz free energy stability criterion for thermal systems is adopted to establish a calculation thermodynamic model of the true critical parameters. A novel optimization algorithm for calculating critical governing nonlinear equations also is developed. By comparing the calculated values and the reported experimental results, the optimization algorithm is shown to be stable and precise. If the linear combination of component critical parameters are used to as the iteration starting values, this algorithm is time-saving and precise, and it can meet the calculation needs of engineering applications, working fluids selection, and explorations for new mixture working fluids.