Based on the theory developed by Moors and Greitzer, a new simplifying approximation, which takesinto account the influence of higher harmonics of rotating waves, is proposed in this paper to get a simplified model of...Based on the theory developed by Moors and Greitzer, a new simplifying approximation, which takesinto account the influence of higher harmonics of rotating waves, is proposed in this paper to get a simplified model of post stall transients in axial compression systems. This approximation leads to a set ofthree simultaneous nonlinear first order partial differential equations. The further investigation of poststall behavior for different response modes of instabilities (rotating stall and/or surge), recoverability,prestall period during stall inception, and the effect of compression system parameters on them canbe carried out by this model and has been discussed in detail in the present paper. It has been foundthat stall inception exhibits a large prestall period in the region with small slope of compressor characteristic, and in this region, final throttle setting, compressor characteristic and time-lag parametershave a strong influence on the period. The inertia parameters of blade rows have a strong influenceon the recoverability of compression systems and the blockage of stall cell at recovery point. Somequalitative comparisons with available experimental results and experience are made, and it shows thatthe proposed model is very simple and reliable.展开更多
Post stall behaviors of a single stage compression system are studied theoretically and experimentally in this paper. A one dimensional nonlinear model, which is able to describe the dynamically post stall behavio...Post stall behaviors of a single stage compression system are studied theoretically and experimentally in this paper. A one dimensional nonlinear model, which is able to describe the dynamically post stall behaviors of the compression system, is applied to simulate the post stall behaviors digitally. The stall types, i.e. , rotating stall and surge, are determined. The variations of annular average parameters while the compression system goes into stall are also calculated exactly. The post stall behaviors are measured on the single stage compressor test rig. The measurement shows that rotating stall and surge appear under different conditions. On the basis of experiments, it is found that the post stall behaviors are influenced remarkably by some factors, such as rotation speeds, construction type and size of the exhaust duct. Good agreement between the simulation and experiments proves that this modeling technique is valid for simulating the post stall behaviors.展开更多
文摘Based on the theory developed by Moors and Greitzer, a new simplifying approximation, which takesinto account the influence of higher harmonics of rotating waves, is proposed in this paper to get a simplified model of post stall transients in axial compression systems. This approximation leads to a set ofthree simultaneous nonlinear first order partial differential equations. The further investigation of poststall behavior for different response modes of instabilities (rotating stall and/or surge), recoverability,prestall period during stall inception, and the effect of compression system parameters on them canbe carried out by this model and has been discussed in detail in the present paper. It has been foundthat stall inception exhibits a large prestall period in the region with small slope of compressor characteristic, and in this region, final throttle setting, compressor characteristic and time-lag parametershave a strong influence on the period. The inertia parameters of blade rows have a strong influenceon the recoverability of compression systems and the blockage of stall cell at recovery point. Somequalitative comparisons with available experimental results and experience are made, and it shows thatthe proposed model is very simple and reliable.
文摘Post stall behaviors of a single stage compression system are studied theoretically and experimentally in this paper. A one dimensional nonlinear model, which is able to describe the dynamically post stall behaviors of the compression system, is applied to simulate the post stall behaviors digitally. The stall types, i.e. , rotating stall and surge, are determined. The variations of annular average parameters while the compression system goes into stall are also calculated exactly. The post stall behaviors are measured on the single stage compressor test rig. The measurement shows that rotating stall and surge appear under different conditions. On the basis of experiments, it is found that the post stall behaviors are influenced remarkably by some factors, such as rotation speeds, construction type and size of the exhaust duct. Good agreement between the simulation and experiments proves that this modeling technique is valid for simulating the post stall behaviors.
