Modares Mechanical Engineering

Modares Mechanical Engineering

The numerical investigation of stator tip sealing with honeycomb on axial flow compressor performance.

Authors
Mohammad Valizadeh 1
Mohsen Behnia 2
Alireza Shahrabi Farahani 2
1 Research of Department of Compressor/ Turbotec Company, Tehran, Iran
2 Turbotec, Tehran, Iran
Abstract
In axial flow compressor there is a gap between stationary and rotating members since the stator vane is fixed at the casing and the shaft is rotating at the root. Also, the pressure increases when the air flows through the stator vanes. Therefore, due to pressure increase and existence gap under vanes, the leakage is inevitable in the stator tip. This leakage can change the flow pattern near the stator tip, which causes more separation. Therefore the loss has been increased so it adversely effects on performance. In this paper, the effect of stator tip sealing with honeycomb on compressor performance is investigated. For this purpose, the 9th stage of a ten-stage compressor is examined in two cases of solid wall and sealing with honeycomb. The numerical results have good agreements with experimental results. The results show that by reduction of leakage at stator tip, the size and depth of tip corner separation decreased significantly leading to loss reduction. Also the effect of the leakage on flow angles shows that to have more accurate analysis of compressor performance, it is necessary to be considered the stator tip leakage. On the other hand, according to same effect of honeycomb on reducing stator tip leakage than solid wall, here the honeycomb roles as an abradable material to prevent direct contact between rotor and stator. Also in analysis of stage the honeycomb can be replaced with solid wall model.
Keywords
Gas Turbine
Axial Flow Compressor
Stator Tip Leakage
honeycomb
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Modares Mechanical Engineering
Volume 18, Issue 2
April 2018
Pages 127-134