Numerical Simulation And Calculation On High Pressure Combustion Of Gas Turbine In Integrated Gasification Combined Cycle With Reheat

Integrated gasification combined cycle power generation technology has played a more important role in the field of thermal power generation because it is clean and highly efficient. How to use the energy more efficiently and environmentally is a significant target in the field of combined cycle power generation. Improving air compression ratio can effectively improve the efficiency of the present combined cycle. Syngas is burned in high pressure if the compression ratio is improved. But there are few relatively research about high pressure syngas combustion at present. In this paper, on the basis of home and abroad gas turbine design experience and combined with the technology of low swirl combustion, a new syngas combustion chamber of low swirl gas turbine combustor was preliminary designed. Numerical simulation are used to study the characteristics of syngas high pressure combustion, such as flame shape, temperature distribution, flow field and pollutant emissions. The aim of this paper is to understand syngas combustion mechanism in the condition of high pressure and to master the burning and pollutant emissions law.On one hand, a new syngas combustion chamber of low swirl gas turbine combustor was preliminary designed in this paper. The combustion chamber adopt partial diffusion combustion model. The fuel flow into the flame tube through the central hole of the low swirler. While the air was rejected into the flame tube through the low swirler channel outside the central hole burning with fuel. The FLUENT software was used to simulate the combustion chamber and the cold flow of syngas combustion was studied by numerical simulation to verify the rationality of the burner structure.On the other hand, the numerical simulation of syngas combustion with high pressure were carried out in different conditions, including different pressure, different power as well as different equivalent ratio. Through investigating the characteristics of syngas high pressure combustion, such as flame shape, temperature distribution, flow field and pollutant emissions to master the burning and pollutant emissions law. Result shows that with the increase of the pressure, length of flame becomes shorter and then to be stable. At the same time, the maximum flame temperature raised rapidly at first and then to be a fixed temperature. While the NOx emissions had upward trend with pressure increasing. Besides, with the increase of power, flame length became longer and the width became wider, the NOx emission had downward trend. Low- speed flow field area became more and more obvious, which is beneficial to improve the combustion stability. Finally, when the ratio of equivalent rose, the Low- speed flow field gradually weakened and even disappeared in the end. So the combustion stability was reduced with the increase of equivalent ratio. To sum up, the level of pollutant emissions was low. Which showed that the new syngas combustion chamber of low swirl gas turbine combustor can effectively reduce the NOx emission.