Analysis of an Auxetic Casing Structure for Tip Clearance Control under Various Temperature and Pressure Conditions

摘要

Using transient Finite Element Analysis, the expansion behavior of a double-walled gas turbine compressor casing including an auxetic inner structure is investigated fundamentally to further improve the tip clearance between the rotor and the inner casing wall during all operating conditions. Therefore, a parameter study is conducted loading the inner casing structure by increasing first the pressure and afterwards the temperature level. In the evaluation part, the radial displacement of the inner wall was focused because this parameter directly influences the tip clearance. In order to compare the results, a reference casing without any auxetic structure was modeled and analyzed. The results show that definitely more flexibility can be achieved, adjusting the radial displacement with inner structural thermopneumatic load variations and verify the potential for improvement when using auxetic structures for compressor casing application.