Analysis Of Flow Field Inside A Flue Gas Turbine And Numerical Investigation Of Impeller Erosion And Heat Transfer Of A Flue Gas Turbine

As one branch of turbo-machinery, a flue gas turbine, which belongs to the category of gas turbine, is a power machine propelled by flue gas. In the current catalytic cracking equipment of petrochemical enterprise, flue gas turbine plays a very important role in energy conservation and environment protection. Very similar to the working principles of gas turbine and steam turbine, in the flue gas turbine the moving blades are propelled by the flue gas and then rotate to generate power. The flue gas is one kind of gas with high temperature and pressure, which is the production from the combustion of some poisonous or harmful gas in the process of chemical manufacture. So, full use of the flue gas has a great meaning for energy conservation and pollutants release reduction.Unlike other general working medium for gas turbine, besides the character of high temperature, there is some amount of solid catalytic particles within the flue gas, which asks for high level design and manufacture of blades considering safe operation. Also, for cooling the rotor impeller and avoid gas ingestion to the cavity between stator and rotor, there must be some coolant flowing in the cavity. All these properties make the flow inside the flue gas turbine really complicated, hence high efficiency and high reliability are the important points of the research for flue gas turbine.The research in this paper is based on practical projects of a petrochemical enterprise and focuses on the following aspects:numerical investigation of the flow field inside a flue gas turbine and optimization of nozzles; numerical investigation of impeller erosion caused by coolant inside a flue gas turbine; numerical investigation of conjugate heat transfer between coolant and rotor impeller of a flue gas turbine. After the analysis, a deep understanding of the inner flow of the flue gas turbine has been produced. Based on the analysis, optimization of nozzles has been accomplished to improve overall performance of the flue gas turbine, which has been proved available in practical use. Combining the theory of two-phrase flow, the erosion at the sharp angle of impeller is due to the exist of both the catalytic particles and the coolant. The analysis of the erosion extent caused by different mass flow of the coolant has also been accomplished. For the research of conjugate hear transfer between coolant and impeller, the temperature of impeller and the flow field of coolant have been analyzed, which finally proves the excellent design of the new sealing.