No.6 M501G Compressor Development

MHI has developed the "G" series; a new gas turbine for the next generation. The G series is a 1500°C class air cooled gas turbine, which has been in operation since 1997.
Controlled Diffusion Airfoils (CDA), designed by Computational Fluid Dynamics (CFD) code, were incorporated into the "G" series gas turbine from the 1st stage to the 8th stage.
In designing the compressor, the latest 3-D compressor blade design system was used.
The overall flow field and performance were calculated by in-house throughflow code, which incorporates all of the experimental data and performance data of the production gas turbine.
To assure the readiness of the new technology when applied to large production engines, several verification steps were planned and carried out successfully.
The first step was researching the CDA to acquire the fundamental cascade data, which included work range from choke to stall, loss coefficient characteristics and turning angle characteristics, as a function of the inlet flow angle.

MF-211 GAS TURBINE

The second step was the rotating model test of the 1st stage of the MF221 gas turbine compressor, which is a half scale model of the M501G compressor. The test was carried out and comparisons were made with the conventional compressor, which was designed using Double Circular Arc airfoils (DCA) for the rotor blades and NACA 65C airfoils for stator vanes, employing the same velocity triangles. The superiority of CDA for efficiency and operating range over those of conventional airfoils was confirmed through this test.

The third step was the design of the MF221 compressor, which is MHI's first gas turbine compressor incorporating CFD designed CDA.
The full-load shop test of the MF221 gas turbine was successfully performed in July 1994.

M-501G GAS TURBINE

Using data measured from the MF221, the design of the M501G compressor was refined.
Takasago verification plant for the M501G gas turbine in early 1997.