回热加热器是火电厂热力系统的重要设备,其运行性能直接影响机组的经济性。本文对纯凝结段回热加热器的动态特性进行了理论模拟与实验研究。将纯凝结段回热加热器按结构划分为蒸汽控制容积、给水控制容积、换热管金属控制容积、外壳金属控制容积等四个控制容积,并分别建立连续方程和能量方程,从而得到回热加热器的动态模型。本文对蒸汽压力瞬态减小工况开展了数值模拟研究,并进行了实验验证,结果吻合较好。
Feedwater heater is an important device in thermodynamic system of power plant, and its operating performance affects the efficiency of the units directly. Focusing on the dynamic behavior of heater, the numerical solutions and experimental researches are presented in this paper. The heater was departed into four control volumes: shell, steam outside the tubes, heat transfer tubes and water inside the tubes. After mass and energy balance equations were given for each part, the dynamic model was established. Finally, the theory results were verified with experimental ones in the steam pressure reduction condition, and the results were almost coincidence.