Research On Flow Characteristics Of Turbineplenum Chamber And The Vortex-reducer With Bafflers

To analyze the effect of vortex-reducers with bafflers, high-speed rotating experimental system without and with reducers was designed. Numerical calculations on static strength of rotation model, leakage rate of labyrinth seal and uniformity of gas supply were carried out. It was found that strength of experimental structure met the stress of 45 forging steel. The first order critical speed of the rotating system was 5359 r/min, while the second order critical speed was over the range of experimental condition.Based on the study of offtake structure, the flow characteristics of typical turbine plenum chamber were investigated experimentally, which had four air intakes and 125 exit holes located in two lines. Experiments were carried out to get the mass flow rate, distribution of outflow and the flow resistance coefficient. The ratio of inlet pressure to outlet pressure, chamber height were changed in experiments, then the flow characteristics of turbine plenum varying with these parameters were achieved. It was found that the holes directly facing the entrance had the maximum flow rate, while flow rate decreased greatly in the region very near those holes. The minimum outflow rate was observed in the holes located at the middle region between inlet holes. Except the holes at these specific positions, the mass flow rate through other holes was almost the same. Experiment’s results showed that the maximum and minimum mass flow rates were only 9.34% and 3.29% of the total flow. With the increasing of inlet pressure and chamber height, the mass flow rate going through turbine plenum chamber increased linearly, while the distribution of outflow didn’t change. According to the experiment’s data, the effect of chamber height was obviously faint compared with inlet pressure. Finally correlation equations about flow resistance were concluded, which took into account the inlet flow conditions and geometrical parameters.