Modeling And Dynamic Simulation For The Marine Supercharged Boiler Steam-Water System

At present, simulation of supercharged boiler working is still in an initial stage at home. The supercharged structure is complicated, whose dynamic mathematical model has nonlinear and multi-parameter coupled characteristic. In the simulation system development of marine steam power plant, the simulation research of marine supercharged boiler plays a key function to the entire unit dynamic characteristic. The main work of this article is to establish the dynamic mathematical model for the marine supercharged boiler steam-water system and to carry out dynamic simulation research in different perturbation.In order to obtain suitable simulation model for some marine supercharged steam-water system, this article has studied steam-water system single-phase region and two-phase region dynamics characteristic on the basis of fundamental physical laws. The thesis has separately established single-phase region distributed parameter dynamics model and lumped parameter dynamics model, as well as two-phase region lumped parameter dynamics model and lumped parameter dynamics model in distributed parameter. On the basics of analysis and compare well-bad points above two methods, in view of the marine supercharged boiler single-phase pipe and two-phase evaporation region characteristics, the supercharged boiler single-phase pipe(economizer, superheater) uses the lumped parameter modeling method, two-phase evaporation region uses lumped parameter in distributed parameter modeling method, which has simplified for several links(steam drum, water wall, and so on). On the basis of the dynamic mathematic model above-mentioned, a four-stage Runge-Kutta time integration scheme is implemented to drive the solution to a stable state; the code for the steam-water system simulation model has been realized using the C++ language. Using the simulation model, this article has carried on dynamic simulation experiment to steam drum pressure, the water level, the steam-gas temperature etc. important target on the different perturbation situation, which are load change, water supply change and so on. The experimental result conforms to both the basic rule and process mechanism of the steam-water system, and has accurately reflected the marine supercharged boiler steam-water system dynamic response characteristic, as while as has proved that the model which is established by this article is rational and precise.Moreover, based on the topic research content, this article also has conducted certain research to the thermodynamic property of working substance and the visualization modeling, which will be more consummated in later work.