Designing the blades in the first stage of a small-scale gas turbine compressor operating under transonic conditions and conducting aerodynamic and structural analyses

Karabulut H., YILDIRIM E.

JOURNAL OF POLYTECHNIC-POLITEKNIK DERGISI, cilt.29, sa.4, 2026 (ESCI)

Özet

The production of gas turbines is currently carried out by a few organizations worldwide. Gas turbines are among the most essential requirements of the aviation and defense industries, and Turkiye has accelerated its gas turbine development efforts in recent years. In this study, a mathematical model was synthesized and applied for the design of the rotor and stator blades that form the compressor stage of an axial flow gas turbine. This model is based on determining the geometry of the camber line and fitting an aerofoil onto it. In the application section of the study, a simulation program was prepared and the applications of the developed mathematical model were carried out. Using realistic inputs, rotor and stator blades with a camber line that is a circular arc were designed. The forces and stresses acting on the designed blades were calculated and analyzed in terms of strength. It was observed that stresses were predominant in determining the cross-section of the rotor blades, while aerodynamic conditions were predominant in determining the cross-section of the stator blades. The analysis showed that the effect of forces, other than the centrifugal force arising from the high speed rotation of the rotor, on the stresses in the rotor blades was negligible. A detailed examination was conducted on a sample blade with a camber line radius of 20 cm, a circumferential speed of 300 m/s, a gyration radius of 25 cm, an angle of attack of 30 degrees, a yield stress of 280 MPa, and a maximum thickness of 3.2 mm. When the mass flow rate is 10 kg/s, the flow around the blade occurs entirely at subsonic speeds. The stress safety factor of the blade was determined to be around 1.66.The remainder of the study examined the viscous flow around the sample rotor blade, some characteristics of which are given above, using a package program. Boundary layer separation was observed in the last 35% of the blade's suction surface.