Simulation Modeling And Dynamic Characteristic Research Of Dual-Pressure Heat Recovery Steam Generator

Energy is the major driving force of national economic development.For the sustainable and stable development of the society,it is necessary to make rational use of resources and transform the utilization of traditional energy into the utilization of efficient and sustainable energy.Heat recovery steam generator is one of the most common and effective means for waste heat utilization,and multi-pressure heat recovery steam generator has been widely used in integrated energy system.Compared with single pressure heat recovery steam generator,the composition of multi-pressure heat recovery steam generator is more complicated.Moreover,it is of great significance to study the dynamic operation characteristics of multi-pressure heat recovery steam generator,which can make use of waste heat and improve the utilization efficiency of the system energy.In this paper,the double-pressure heat recovery steam generator of an integrated energy system was taken to explore dynamic operation characteristics.The dynamic mathematical model of those typical components(economizer,evaporator and superheater)were established based on energy conservation equation,mass conservation equation and heat transfer equation.Then,Fortran was used to write the dynamic simulation model algorithm of each subsystem.Results show that the error between the calculated value and the designed value of the model is less than 1%.The dynamic response characteristics of drum pressure,drum water level,steam temperature,steam flow,and steam pressure were investigated by adding 10 % step disturbance of flue gas temperature,flue gas flow,feed water flow,and feed water temperature,respectively.Simulation results show that the disturbance of flue gas temperature and flue gas flow had a greater influence on the parameters of the high-pressure system,while the disturbance of feed water flow and feed water temperature had a greater influence on the parameters of the low-pressure system.Finally,three optimization algorithms(Genetic,Particle swarm,and Gravitational search)were employed to calculate the perform parameters,and the optimal value of each output parameter was obtained.The efficiency of heat recovery steam generator is81.25%.After optimizing the temperature value of the intermediate node,the maximum efficiency of the heat recovery steam generator is 83.32%(Genetic),83.37%(Particle swarm),and 83.45%(Gravitational search),respectively.In addition,it can be concluded that Gravitational search optimization algorithm has better effect than other optimization algorithms for the heat recovery steam generator.