Load split design strategy of tandem stators in a highly loaded micro axial compressor

Abstract

To investigate the load split (LS) effects on the performance and flow mechanisms of a cantilevered tandem stator in a highly loaded micro axial compressor, three typical tandem blade schemes were thoroughly studied from multiple perspectives using steady-state numerical simulations. The results show that in the LS design of the tandem blades, the trade-off effects between highly and lowly loaded conditions are essential to achieve superior overall performance. The gap jet serves a pivotal function in leakage flow behaviors, acting as a vital link between the leakage flow from the front blade (FB) and rear blade (RB). Furthermore, the mixing effects between the front blade wake and gap jet is one of the main entropy generation sources in the tandem stators. In addition, the spanwise LS distribution remarkably affects the load distribution of the stator in spanwise direction by altering the body force. Specifically, in the tandem stators with lower LS, the overall load near the hub is smaller, but in the range of the midspan and near the casing, the overall load on both the rotor and stator is increased. The former increases overall efficiency, while the latter triggers an earlier stall near the rotor tip.