Numerical Simulation Of Trapped Vortex Combustor With Inclined Struts

Based on the published research, this paper proposes a new aerodynamic structure, and studied the turbulent flow and combustion characteristic of TVC under such structure by numerical simulation.In order to validate the advantage of TVC with inclined struts, compared the characteristic of TVC with and without inclined struts by numerical simulation. The results show that though the total pressure loss is increased by inclined struts, the combustion efficiency is obviously increased with adding inclined struts. After adding inclined struts, the total pressure loss increased from 4.4% to 7.7%, but the combustion efficiency increased from 69.33% to 99.8%. Inclined struts can still enhance the mixing effect in combustor by analyzing the characteristic of TVC under coordination field.In order to optimize the structure of the TVC with inclined struts, numerical simulation of TVC with different position of guide vane, number and the inclined angles of inclined struts. The results show that the length of guide vane in vortex and the distance between guide vane and the front wall of vortex have little effect on the characteristic of the combustor. With the increasing of distance between guide vane and the inlet wall, mainstream gas rounded inclined struts, hindering the flow, which increases the total pressure loss is, the maximum value of the total pressure loss is 8.5%. At the same time, the combustion efficiency increases, the highest value is 99.84%. With increasing the number of inclined struts, the combustion efficiency and total pressure loss increase, the temperature coefficient of the combustor exhaust first decreases and then increases. The ratio of width and height of trapped vortex should be in around 1. When the ratio is small, the size of the vortex in the cavity of the combustion chamber is too small. When the ratio is large, the vortex size increases, it is not conducive for gas which has been mixed combustion to flow out of the vortex area and it has disadvantage for combustion in primary zone.The inlet velocity has little effect on the combustion efficiency of TVC with inclined struts, but it has a great effect on total pressure loss(when the inlet velocity is 60m/s,the total pressure loss is 10.45%). Inclined angles of inclined struts has a great effect on total pressure loss, the maximum value is 9.1%, and the minimum value is 7.1%.After determining the optimal structure, numerical simulation on combustor withdifferent influence factor to study the characteristic of combustion and flow of TVC based on the optimal structure.