| The real size model of straight-through labyrinth seal in areo-engine was used in this thesis. Experimental and numerical studies were carried out to investigate the characteristic of flow and windage heating at rotational and static states.All the experiments were carried out in a high speed rotating facility built in AVIC GTE. Pressure ratio (1.05～3.0), rotational speed (0～12000r/min), Reynolds number(1500～25000) and sealing clearance(0.45mm～1.0mm) were changed to study the flow characteristics,pressure distribution and windage heating. The discharge coefficient, temperature rise varying with these parameters was concluded from the experimental results. Based on the experiments, CFD numerical simulations were applied furthermore. The influence of different turbulence models on computational results is also compared. The detailed distributions of pressure,velocity and temperature in straight-through labyrinth seal were gotten.With research work above accomplished, main results are shown as follows:(1) Both in static and rotational states, discharge coefficient increases with the increase of pressure ratio and increases when the relative sealing clearance increases. The discharge coefficient is more sensitive to geometry size than to pressure ratio.(2) When the rotational speed increases, the discharge coefficient is reduced. There exists a certain Reynolds number value and the rotational speed has't evident effects on discharge coefficient when the Reynolds number in experiments is higher than this value.(3) Discharge coefficient reduces with the decrease of Reynolds number. And this trend seems to be more distinct in low Reynolds number cases than higher Reynolds number cases.(4) An engineering correlation equation for straight-through labyrinth seal is obtained and it fits the experimental results very well.(5)With the increasing of pressure ratio,Reynolds number and relative sealing clearance, the temperature rise is reducing. And it increases when increasing rotational speed. |
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