Multi-stage Axial Compressor Internal Flow Field Analysis And Design Optimization

This article is funded under the National973Project and combined with steel enterprise energy needs. In the steel industry, because of the changes in the steel production process and the seasons, the axial compressor are often in the condition of variable running state. So the compressor with a better variable conditions performance is needed. In order to adapt to the modern fast-paced, high-efficiency production requirements, we need to accelerate the speed of feeding the blast furnace equipment, thus requires a higher pressure ratio.Three-dimensional viscous flow filed numerical simulation was carried out for a13-stages axial-compressor in this paper. For the flow separation at the corner of the first stage stator blade suction side is more serious, this article will focus on the analysis of positive curved stator impact on compressor performance. The results show that optimization modification can significantly improve the pressure ratio, adiabatic efficiency and surge margin of the13-stage compressor, while stage matching good, but it can also increase the risk of instability at the root of the third stage rotor blade.In addition, by analyzing the influence of stator hub gap on the aerodynamic performance, we find that computation with stator hub gap and end wall rotation can obviously improve aerodynamic performance and compressor stability, because that both the moving direction of the end wall and the leakage flow direction is opposite with the separation vortex direction at the corner of the stator blade suction side. In the stationary end wall boundary conditions, flow characteristics improve as the gap increases; In the rotating end wall boundary conditions, when the gap is increased to a certain extent, flow characteristics decrease as the gap increases.In the new multi-stage compressor design process, in order to shorten the design cycle, increase design reliability and reduce design costs, compressor zero-staging is an effective way to increase both the pressure ratio and the mass flow rate. Based on the original13-stage axial-compressor, zero-staging is used to improve the design pressure ratio in this paper. Calculated to determine the final design through iterative, the original13-stage axial-compressor mass flow successfully improved by9.5%, the pressure ratio increased by18%.Through the numerical simulations and the above analysis, we can conclude that the resultant compressor met the new working condition requirements with good match operating characteristics. The zero stage improved the base compressor operating characteristics and stability.