Effect of the Primary Hole Parameters on Combustion Performance of Dual-Stage Swirl Model Combustor

A numerical simulation on the model combustor of dual-stage axial swirler and primary hole was carried out by Fluent. We compared and analyzed the effects of different geometric parameters and layout of the primary hole on the combustion efficiency, total pressure recovery coefficient, Outlet Temperature Distribution Factor (OTDF) and NOx emission of the model combustor under the same flow distribution, the same area and axial position of the primary hole. The results show that the different geometric structure and circumferential layout of the primary hole have an influence on the penetration depth of the transverse jet in the combustor, affecting the distribution of oil and gas and the range of high temperature zone, making the performance of the combustor change greatly. Among the three structural schemes, the structural layout with the largest number of the primary holes and the smallest diameter (model-3) has the worst performance, and the structural schemes with larger diameter (model-1) and medium diameter (model-2) show similar performance. Under various working conditions, the combustion efficiency and outlet temperature distribution coefficient of model-1 are better, and the NOx emission of model-2 is relatively lower.