| 摘要 |
Described herein is a device comprising: a chamber wall comprising outer and inner surfaces, wherein the inner surface encloses a lobed chamber with a plurality of lobes and the inner surface comprises segments of arcuate surfaces, each of the segments of arcuate surfaces being tangent with its immediate neighboring segments, and wherein the chamber wall further comprises channels connecting the outer surface and the inner surface of the chamber wall and/or channels through an end surface of the chamber wall; a lobed piston configured to translate along a circular path relative to the chamber wall, the outer surface of the piston and the inner surface of the chamber wall engaged during translation; and holes fluidly connected to the lobed chamber and configured to allow fluid discharge from the lobed chamber through the holes and to prevent fluid flow into the lobed chamber through the holes. |
