Leakage effects on the performance characteristics of a regenerative blower for the hydrogen recirculation of a PEM fuel cell

Due to their compactness, lightness and low manufacturing costs, regenerative blowers are considered as interesting and suitable machines for hydrogen recirculation in Proton Exchange Membrane (PEM) fuel cells (FC) for automotive applications. In this paper, the experimental performances of a hydrogen regenerative blower with backward-oriented vanes are presented for different impeller-casing clearance values, in order to better investigate the influence of leakages on the head and efficiency characteristics of the machine. A 1D theoretical model, already proposed by the authors in previous works, has also been applied to the machine, in order to better interpret the result obtained during the experimental activity.