Numerical Simulation And Experimental Study On Dynamic And Combustion Characteristics Of 410T/H Six-corner Tangential CWS And Oil Boiler With A High Length-width Ratio

The Nation's Economic and Commercial Committee illuminate: in the No.15 layout plan that our nation shall economize and substitute combustible oil 16 million tons, among which the combustible oil substituted shall get 12.62 million tons, accounting for 78.9%. Spirited by the guide of oil substituted by coal, Maoming Thermal Power Station decided to retrofit the 410T/h boiler from combusting oil to combusting CWS, which is emphasized by the Nation's Economic and Commercial Committee, Provincial Economic Committee and the YueDian Company. At the same time, the project was listed as one of the Nation's No.2 important technical reconstruction "Two high and one Good" projects.We are facing many difficulties during the reconstruction, such as we have no instructions and experiences on the same unit boiler retrofitted to combust CWS from oil in the world, which is the special structure of six-corner tangentially firing with a high length-width ratio. Therefore, the systemic study on the project is seriously needed. Based on reconstruction of the Maoming Thermal Power Station 410T/h boiler from combusting oil to CWS, we carry out numerical simulations and experimental studies on dynamic and combustion characteristics in the furnace of the boiler of this type in detail, which will provide experimental and theoretical foundation for the six-corner tangentially firing boiler with a high length-ratio ratio and the technology of substitution of CWS for oil, etc.Firstly, we carry out cold model experimental, field black furnace test and numerical simulation on aerodynamic field in a high length-width ratio, six-corner tangential boiler. Through the study we get knowledge about principal rotation flow, secondary vortex flow, the velocity near the furnace wall, the outlet velocity misalignment, and the influence of the tangential or counter-tangential arrangement overfire air over the flow field in the furnace.Different from the ordinary quadrangular arranged boiler, hexagonal-arranged burner boiler with a high length-width ratio is unsymmetrical structure, which will influence the aerodynamic field variously. On the basis of model experiment and numerical simulation, a study on aerodynamic field in the boiler during absent-angle running has been carried out. The influence of each burner jet upon the central flow field and the velocity deviation of the front wall flue gas have been investigated in detail, the rules of in-boil aerodynamic field when absent-angle running have been discovered. Through analyzing and comparing the aerodynamic field when partial...