Gerotor Pump CFD Simulation, ANSYS Fluent Training

A pump is a mechanical device for moving and transferring all liquids from one place to another. In this way, by increasing the pressure, pumps cause liquids to move to a higher height (by increasing the head) and even lower (such as tanks). The pump takes mechanical energy from an external source, such as a motor, and transfers it to the fluid passing through it.

As a result, the energy of the fluid increases after leaving the pump.

The energy transfer to the pump fluid is done in two dynamic and displacement methods. Therefore, pumps are divided into positive displacement pumps and dynamic or non-positive displacement pumps. Positive displacement pumps are divided into two groups: rotary (such as gear, lobe, and vane) and reciprocating (piston and diaphragm).

One of the most common pumps to increase the hydraulic power of a fluid is a gerotor pump. Gerotor pumps move liquids using gears.

Gerotor pumps consist of two gears that rotate in the same direction, so one gear is inside the other. When two gears make contact with their teeth, fluid is trapped. Now, when the teeth are separated from each other due to rotation, high-pressure fluid is rotated through the ribs to the outlet.

Gerotor pumps are similar to internal gear pumps, with one difference. Gerotor pumps are internal gear pumps without a crescent.

In this project, we simulated the water flow inside a gerotor pump. We aim to model the rotation of two gears inside the pump. The gears’ rotation changes the fluid’s behavior in the pump momentarily. So, the mesh of the computing domain deforms over time.

The problem numerically simulates the Gerotor Pump using ANSYS Fluent software.
We design the 2-D model with the Design Modeler software.
We mesh the model with ANSYS Meshing software, and the element number equals 511,82.
We perform this simulation as unsteady (Transient).
We use the Dynamic Mesh Model to define deforming and moving zones.
We use the user-defined function (UDF) to define the rotational motion of gears.
You can read more about this simulation and order its comprehensive training video by clicking on the link below: