Numerical Simulation On The Characteristics Of Turbulent Flow Of Advanced Vortex Combustor With Disc Blunt Body

To improve the stability combustion and reduce the pollutant emission of the gas turbine combustor, Ramgen developed a new concept for gas turbine combustor:Advanced vortex combustor(AVC). Because of the characteristics of having a special way of flame stabilization, a high combustion efficiency and low pollutant emission, AVC has been paid attention to widely. The technology is still in the exploratory stage. The numerical simulation of turbulent flow under cold and combustion conditions has been carried out in this paper.To investigate the best relationship of bluff-body structural parameters, the influence of disc bluff-body structural parameters on the cold flow field and the total pressure loss in the outlet of AVC has been studied, and the results show that the vortex in cavity can be the most stable and the pressure loss can be the least when structural parameter is R1=35mm,R2/R1=0.6,S1/R1=0.8. Compared with the radius of a blunt body and concave cavity length, the thickness of the bluff body of combustion chamber has little effect on total pressure loss.On the basis of the best structural parameter of AVC(R2/R1=0.6,S1/R1=0.8), adding a third disc blunt body forming the three blunt body dual cavity AVC. The numerical simulation under cold condition has been carried out to get the best structural parameters of the third blunt body. Studies suggest that when S2/R1=0.8、R3/R1=0.6, AVC has advantages of good flow field, stable combustion, lower total pressure loss. Vortex after Blunt body is associated with blunt body radius, the greater radius, the greater vortex, and smaller relationship with the third blunt body thickness.The effect of incoming velocity on flow field of the combustor is studied with the best relationship of bluff-body structural parameters. The results show that with the increase of the incoming velocity, the total pressure loss increases. The vortex keeps stable with different incoming velocities. AVC has a good performance of stabilize the flame in cavity. Stable combustion with lower pressure drop can be achieved with appropriate incoming velocity.Based on numerical simulation under cold condition of three disc blunt body AVC, take methane as fuel, the characteristics of turbulent combustion is numerically simulated, to study on AVC by changing equivalence ratio, inlet temperature and velocity. The results show that influence of inlet velocity on the three disc blunt body AVC is small, and choice of combustion scheme of improving the inlet temperature and selecting low equivalence ratio like this, turbulent combustion under the premixed condition on AVC is very profitable.