A new synchronal rotary multiphase pump(SRMP)is proposed and its structural characteristics and working principle are described. With the dynamic model established for the key moving parts

the dynamic characteristics of the pump and the influence of main structural parameters on the dynamic performance are investigated. The power input of a prototype of the SRMP is tested experimentally. The results show that the pump has the advantage of simple structure and smooth running. The relative angular velocity between the rotor and the oil cylinder is less than 10% of the rotor angular velocity. The forces on the pump slide vane decrease with the decrease of the relative eccentricity and the slenderness ratio. The loads on bearings decrease with the increase of the relative eccentricity or the decrease of the slenderness ratio. Additionally in the working pressure range of 0.5-2.5 MPa

the deviation of the power input tested and calculated is in the range of 17.3%-35.1%

the friction loss in the prototype occupies a large part of the total power consumption. It seems that the pump needs to be improved further.