Numerical Investigation of Transonic Axial Compressor Rotor With Leading‐Edge Tubercles

ABSTRACT The efficiency of a jet engine heavily depends upon the efficiency of its compressor. This study investigates the impact of leading‐edge tubercles on a transonic axial compressor. For this purpose, a CFD analysis has been performed for NASA Rotor 37. The method of investigation is based on the numerical solution of steady‐state, three‐dimensional Navier–Stokes equations using k‐ ω ‐SST (Shear Stress Transport) turbulence model. The accuracy of simulations is ascertained by comparing the numerical data with the available experimental data. Several configurations are considered by changing different tubercle parameters: amplitude, wavelength, and span‐wise location of the tubercles on the rotor blade. The results indicate an increase in efficiency for all the configurations considered for the modified rotor as compared to the corresponding baseline rotor with a maximum increase of 0.52%. The improvement in efficiency can be attributed to the higher outlet pressure achieved by the modified blade, which is 1.91% greater than that of the baseline blade. Mach number contours show that the location of the shockwave has been moved further downstream in the optimized case. Furthermore, new vortices are observed to be generated near the middle of the chord on the suction side of the tubercle model. Vortices formation has resulted in the redirection of the surrounding flow in an axial direction. Simultaneously, it has also contributed to loss which is associated with temperature increase. However, pressure gain at the outlet accomplished by redirection of flow outweighs the drawbacks of loss associated with temperature increase thus reducing the overall losses.