Experimental study of the effect of tangential swirling injection on diffuser effectiveness

The experimental data on studying the tangential swirling injection effect on the effectiveness of a conical diffuser with an aperture angle of 18° and the expansion ratio equal to four are presented. It has been indicated that the effect becomes maximal for a given diffuser at an insignificant initial thickness of the boundary layer, when the injected jet swirling angle is 15° and the relative injection rate is 7.7%, as a result of which the pressure increases from 0.48 to 0.79 if the injected jet energy is taken into account.