A Study Work on Lobe Pump

Lobe pump rotor profiles radius of base circle, addendum circle and root circle are closely connected with pressure angle. The change of pressure angle has some effect on lobe pump performance. This paper focuses on two-dimensional profile lobe pump and introduces involute rotor profiles and pressure angle parameter equation. We used geometry and two rotor mesh characteristics to establish lobe pump models of different pressure angles. Monitored the lobe pump’s pressure and velocity of input and output cross section. We used the K-Epsilon turbulence model and the dynamic meshes to compute the two-dimensional turbulence flow field of the lobe pump and obtained the pressure and velocity pulsation picture of different models and speeds. The results show with increasing pressure angle, the velocity of output decreases. The fluctuation of velocity is kept almost constant. When the pressure angle is 45°, the lobe pump has good comprehensive properties. The increasing of rotor speed makes the output flow and the oil absorption pressure increase. But the pressure fluctuation is acute. The lobe pump has vortex and leakage phenomenon in work progress. It will cause energy losses and decrease efficiency.