Improving the Performance of Regenerative Blower

Regenerative machines are those machines that can allow high heads at small flow rates and performance curves with very stable features. Unfortunately the efficiency of regenerative blowers are not high it is usually less than 50 % thus this book aims to study the effect of inlet blade angle and blades number for improving efficiency by minimizing the losses as much as possible. An incidence loss is one of these losses that appears usually at the blade inlet regions. The increase of angle of attack (AOA) leads to the increase of the incidence loss (Shock loss). Since decreasing the effect of the shock losses and vortices could be obtained by changing the inlet blade angle and the blade numbers the present work focuses on the study of the effect of inlet blade angles of (90⁰ 115⁰ 125⁰ and 135⁰) and blades numbers of (21 31 41 and 51) on the performance of regenerative blower at different rotational speeds of (1000 2000 and 3000 rpm). The investigations are carried out analytically using two different 1-D models experimentally and numerically by the CFD.