Design and Testing of a Controlled Diffusion Airfoil Cascade for Industrial Axial Flow Compressor Application

Abstract

Similarly as in jet engine development, modern design methods are used today to improve the performance of industrial compressors. In order to verify the loading limits, a cascade profile representative for the first rotor hub section of an industrial compressor has been designed by optimizing the suction surface velocity distribution using a direct boundary layer calculation method. The blade shape was computed with an inverse full potential code and the resulting cascade was tested in a cascade windtunnel. The experimental results confirmed the design intent and resulted in a low loss coefficient of 1.8% at design condition and an incidence range of nearly 12° (4% loss level) at an inlet Mach number of 0.62.

Study on the behavior of streamwise vortices formed between leading edge tubercles in a compressor cascade

“…The scaling method in the spanwise direction with periodicity conditions is validated in the following section. The numerical method mentioned above was validated in a linear cascade built with the controlled diffusion airfoil (Steinert et al, 1991). This cascade is similar to the baseline cascade investigated in the study, in terms of the loading and flow phenomenon.…”

Numerical loss analysis in a compressor cascade with leading edge tubercles

“…A linear cascade constructed with the controlled diffusion airfoil (Steinert et al, 1991) was simulated to validate the numerical method mentioned above. The loading and flow phenomenon in this cascade was similar to the investigated cascade in the paper.…”

Inlet Flow Angle Determination of Transonic Compressor Cascades

“…The operation of the tunnel in the subsonic range is described in detail by Steinert, Eisenberg, Starken (1990).…”

“…By varying the inlet flow angle of the cascade SKG-FVV2.2 (Steinert, Weber, Starken 1984 andWeber et al 1987 Gradient d13 1 /dM s versus inlet Mach number of a supgrcritical airfoil velocities, the inlet Mach number may be determined from the measured surface Mach number at this chord position because the velocity here is independent from the inlet flow angle. Ahead of this point, the surface Mach number changes linearly with the inlet flow angle.…”

“…The test results confirmed t o practicability of this method. (Steinert, Eisenberg, Starken 1990). The inlet periodicity may be checked either by traversing with a single probe or by mounting several probes in the inlet reference plane, where the inlet velocity is measured by sidewall static taps.…”