Influence of rotor profile geometry on the performance of an original low-pressure gerotor pump

•Novel design concept for gerotor pump featuring radial ports is introduced and discussed.•Theoretical analysis on the influence of rotors profiles on pump performance is needed.•Considered geometries for lobes profiles are: traditional circular, narrow and enlarged ellipse.•Benefits and issues of each solution are presented and discussed.•Asymmetric lobe concept is introduced and its merits assessed.

Gerotor pumps are a common choice for low-pressure fluid systems, such as fuel or lubricating oil distribution. Starting from a patented solution, gerotor devices featuring radial ports are presented and discussed: major sizing constraints due to low-pressure operation are defined and their influence over rotor profile geometry assessed. In order to maximize the pump displacement, a comparison between several profile geometries is set up: circular, elliptic and asymmetric lobes are presented and mathematically described using a simple unified approach, while the comparison indexes are defined and discussed. Pros and cons of each geometry type are finally assessed.