0D models of axial piston pumps/motors

Since 1999, different types of axial piston machines have been studied using lumped-parameter models developed in the AMESim environment (currently Simcenter Amesim). A customized component library was created to properly simulate the specific geometry of the machine. The model is fully parametric, and all geometric quantities, derived from input data, are automatically evaluated by the simulation code. At the start of each simulation, parameters are first checked for geometric consistency. Particular care was taken in calculating the flow passage areas: in this respect, the dimensions and number of kidney-shaped slots, relief grooves, and defining angles can all be varied at will.

In addition to hydraulic quantities, the simulation model also evaluates the forces exchanged within the pump. More specifically, the entire pump unit is broken down into its constituent components (swash plate, slippers, pistons, barrel, and so on), and rotational and translational equilibrium conditions are expressed for each of them along the three axes of a Cartesian reference frame.

Figure 1 shows the pump model with three displacement controls (absolute and differential pressure limiters, and torque limiter).

Figure 1

Figure 2 shows the user-friendly interface for setting the geometric parameters of swashplate axial piston pumps. A similar interface is available for defining the parameters of the port plate.

Figure 2

Figure 3 shows a pump mounted on the old test rig used for the experimental validation of the simulation model, while Figure 4 presents the delivery pressure ripple at two different angular speeds.

Figure 3

Figure 4

More analyses and details are available in:

CORVAGLIA A, RUNDO M, 2018: Comparison of 0D and 3D Hydraulic Models for Axial Piston pumps

MANCO' S, NERVEGNA N, LETTINI A, COLELLA L, 2003: Simulation of a split delivery pump

LETTINI A, COLELLA L et al. 2003: Studio e simulazione numerica del limitatore di coppia ...

MANCO' S, NERVEGNA N, LETTINI A, GILARDINO L, 2002: Advances in the simulation of axial piston pumps

GILARDINO L, MANCO' S, NERVEGNA N, VIOTTO F, 1999: An experience in simulation: the case of a ...