Analysis, design and manufacturing of solarised gas turbine compressor

[摘要] ENGLISH ABSTRACT: An existing three-dimensional fluid mechanical design of a compressor is reviewedand compared to mean-line simulation results obtained using the Comp-Aero® compressor design code. Mean-line simulation results give a compressortotal-to-static pressure ratio of 3.2. The three-dimensional CFD analysis performedusing ANSYS CFX® calculates a total-to-static pressure ratio of 3.4.This is an increase of 31% from the pressure ratio of the currently installedcompressor (2.6). ANSYS Mechanical® is used to perform finite element analysesfor deformation, stress and vibrational behaviour. The maximum calculatedaxial deflection is 0.24 mm. The calculated maximum equivalent stress is218 MPa. All vibration modes occur at frequencies higher than the operatingspeed of the compressor. The first damped frequency occurs at 837 Hz whichrepresents and over-speed condition of 9.24%. Over-speed simulations to 110%operating speed calculate a maximum stress in the impeller of 264 MPa. Thisis 1.8 times less than the yield strength of Aluminium 7075 which was usedto manufacture the part. Axial forces due to the increased outlet pressure ofthe compressor are calculated. The total load on the angular contact bearingincreased from 376 N, as experienced with the old compressor, to 955 N whenusing the new compressor. The new impeller and diffuser are designed usingthe Autodesk Inventor® CAD program. The components are machined usingfive- and three-axis computer-aided milling.

[发布机构] Stellenbosch University