氨氢融合燃气轮机燃烧室数值模拟研究

To achieve carbon-neutral operation of gas turbines while maintaining zero carbon emissions and high combustor performance, ammonia-hydrogen blended combustion technology was adopted to evaluate the combustion and emission characteristics of ammonia-hydrogen blended fuel in a 6 MW-scale gas turbine combustor. A geometric model was constructed based on the actual combustor configuration, dis-cretized with polyhedral meshes and local refinement in the primary zone. Numerical simulations were performed for ammonia cracking ratios ranging from 0% to 40% using the Reynolds-avereged Navier-Stokes (RANS) approach coupled with the flamelet-generated manifold (FGM) model. Key performance parameters including flow field structure, combustion efficiency, outlet temperature uniformity, pressure loss and pollutant emissions were systematically analyzed. Results indicate that the RANS-FGM method achieves satisfactory accuracy in predicting NO_x emissions, with a mean error below 20% . The ammonia cracking ratio significantly influences combustion behavior, increasing the ratio enhances hydrogen content, which effectively promotes ammonia oxidation and improves overall performance. At cracking ratios of 20% to 25%, combustion efficiency exceeds 99%, unburned ammonia volume fraction remains below 3. 5 × 10 ^{- 4}, and NO volume fraction is around 3. 76 × 10 ^{- 4}. Optimal outlet temperature distribution uniformity is achieved with overall temperature distribution factor (OTDF) as low as 0. 216, while the total pressure loss remains stable at approximately 0. 035. A recommended range of ammonia cracking ratio of 20% to 25% enables clean and efficient combustion with relatively high economic feasibility.