Modeling of Crescent‐Type Internal Gear Pumps Considering Gear Radial Micromotion

Abstract

This paper presents a numerical modeling approach for investigating crescent‐type internal gear pumps (CIGPs) considering radial micromotions of both gears. The modeling approach couples a lumped parameter pressure solver on the bulk fluid domain, with a transient computational fluid dynamics film simulator based on transient gap geometries solved from the gear loading forces. Simulation results on a commercial unit shows that for a wide range of operating conditions, the model gives volumetric efficiency predictions with errors less than 2 % comparing to measurements. To highlight the importance of considering radial micromotions, the paper also provides the results achieved assuming nominal position for both gears.

Research of the Meshing Performance of New Concave-convex Ball Teeth

“…Hydraulic pump as the core power element of the hydraulic system, its performance largely determines the working performance of the hydraulic system, is one of the most important research direction in modern hydraulic transmission [6]. Internal gear structure applied to water hydraulic pumps can significantly reduce the volume and weight of the water hydraulic pump itself, the structure is simple and compact [7], but the physicochemical properties of water and mineral oil are very different, to the design of water hydraulic internal gear pumps bring a lot of difficult problems, the need for a series of key technologies such as material matching, friction and wear and processing and manufacturing of in-depth research [8]. Harbin Institute of Technology to Japan Fujikoshi (NACHI) IPH oil hydraulic internal gear pump as a prototype, the pump axial and radial gap sealing device according to the physical and chemical properties of water re-design and manufacture, the development of a water-hydraulic internal gear pump, the results show that in the working pressure of 4MPa, the pump volumetric efficiency of 88%, the overall efficiency of 68%, 6.3MPa volumetric efficiency of 85%, total efficiency of 74% [9]; Zhejiang University proposed a new type of involute internal gear pair, the gear pair with full tooth profile and external gear tooth profile conjugate internal gear, and for the physicochemical properties of water, the design of the water lubrication hydrostatic support, but processing and manufacturing prototype experimental results and theoretical volumetric efficiency is a large difference, failing to meet the design requirements [10].…”