基于比拟思想的回热器热惯性表征及对 S-CO₂ 循环负荷变化速率的影响规律研究

In this paper, the S-CO₂ cycle dynamic model considering the thermal inertia of the recuperator is constructed. The flow inertia is characterized by the total channel volume and the fluid volume flow. The heat transfer inertia is characterized by the heat transfer quantity and the thermal conductivity. The dynamic performances of the S-CO₂ cycle under mass flow control and temperature control are compared. The changes of S-CO₂ cycle dynamic performance parameters such as real-time efficiency and load change rate with the key design parameters of the recuperator are analyzed. The mathematical expression of S-CO₂ cycle load change rate, fluid channel volume and thermal conductivity are fitted by multiple regression analysis method. The results show that the mass flow control is more effective. The efficiency loss is 0.72% and the load change rate is 10 %/min. When V=1.5V₀ and kA=0.5kA₀, the load change rate of S-CO₂ cycle is the highest, which is 11.32 %/min.