Study On The Effect Of Water Jet On Plasma Ignition And Combustion Process

At present, thermal power plays a leading role in the development of electric power in China. Large capacity, high parameter arid environmental protection have been a major tendency of power plant, in which efficiency and environmental protection have become the primary task of the thermal power technology. As a new, efficient and environmental ignition technology, plasma ignition and stable combustion technology has received extensive attention. In order to give full play to the characteristics of plasma ignition technology, improve combustion efficiency and promote low-volatile coal ignition and burn, this thesis discusses about a new combustion technology-Plasma Ignition Technology after water jet. A detailed research about numerical simulation of this new ignition is presented in this paper.Based on the coal combustion dynamics and the theory in coal pyrolysis and gasification, numerical value in the process of water jet on plasma ignition and combustion is calculated with the help of plasma heat transfer characteristics, the FLUENT software together with appropriate mathematical model.According to the character of plasma generator anode, fit two equations to express temperature and velocity. As the boundary of plasma inlet, we compile the source code through the C language, and loaded the code into FLUENT. The turbulence model uses the standard k-εturbulence model to simulate gas transport; turbulent combustion model chooses mixture-fraction/PDF; and radiation model is the P-1 radiation model; pyrolysis model (Volatile analysis model) chooses the two-competing-rates; coke combustion model uses the kinetics/diffusion-limited.After simulation, the mass distribution of the internal temperature and other gaseous products (CO, H2, O2, CO2 and H2O) in the water jet on plasma ignition and combustion process. Compared with the data from traditional plasma ignition combustor, the new combustion technology is analyzed, and some effects caused by the new burner are discussed. Analysis and study mainly from the following considerations:(1) Effect of water jet on the combustion chamber temperature field;(2) Effect of water jet on the CO and H2 production; (3) Effect of water jet on the combustion products like CO2 and H2O. By the changes in cross section of the ignition burner, the average CO and H2 concentration and the average temperature of export section curves of the ignition combustor are gained. At the same time, consider the followed factors:(1) The relationship between the production of CO and H2 and the amount of water jet; (2) The relationship among coal elements, the production of CO and H2, and the amount of water jet. Then we will get the the best amount of water spray in the highest yield of H2 and CO, and the other parameters.