Engineering Thermal Analysis Of Sic Refractory Brick Wall For Supercharged Boiler

As a general power device, supercharged boiler has the advantage of high efficiency and high reliability. Material and structure of supercharged boiler fireproof brick wall have a major impact on boiler performances. Temperatureshift can result in heat stress because brick wall components constrain each other but have different heat expansion coefficients. Overlarge heat stress may destroy the brick wall components and then the main body of boiler. For this reason, people had paid great attention to this and a lot of research work about supercharged boiler fireproof brick wall was carried, it is significant to ensure boiler wall in good condition and safety running for the work.This dissertation deals with the study of carborundum fireproof brick wall of supercharged boiler for vessels. Combined with thermophysics performances of carborundum fireproof brick wall gained by tests, 3D solid model and finite element model of fireproof brick wall are set up based on heat transfer theory and finite element principles. Transient temperature field distributions with different heating rates and temperature reduction conditions under several liner and unliner start modes are simulated, and the temporal change of brick wall components temperature field is shown. What's more, temprature viration laws of some typical components are contrasted and analyzed.In the matter of heat stress analysis, heat stress is cuculated based on transient temperature field date, and the maximum transient heat stress which changes along with variation of time under different working conditions is gained. Heat deformation and swell increment during the boil runing process are caculated and the effecting law of carborundum fireproof brick wall thermophysics performance parameters on brick wall temperature field and heat stress field is analyzed, which provides guidance for brick wall design and carborundum brick study.From the therotical simulation, it can be concluded that, the higher the heating rates, the bigger the maximum heat stress, and the offside heat transfer coefficient have little impact on maximum transient heat stress while the inside heat transfer coefficient have remarkable impact on maximum transient heat stress. The thermoanalysis results combined with carborundum brick performance tests will do much help to determine boiler starting mode, heating rate and temperature reduction conditions in order to guarantee the safety of fireproof brick wall and even the boiler.