Modelling a propeller pump or a fan with Heliciel: export to Mecaflux Pro3D

To model a propeller pump or a fan with Heliciel, you design the ducted propeller in the software, then export it to Mecaflux Pro3D: the pump becomes a pressure-versus-flow-rate curve, which is used to find the operating point of a network connected to it. The export is started with the menu entry Export pump/Fan to Mecaflux Pro3D.

In this page:

1: Propeller pumps and axial fans

Axial flow pumps, of the propeller pump type, are suited to producing high flow rates. The fans of machine chip suction systems, air extraction systems, circulators, axial pumps or jet skis are of this type: axial propeller pumps. The page on axial pumps and water jets and the one on ventilation describe these machines.

Heliciel allows the design of this type of pump. The software provides the performance, the optimum twist and the 3D IGES file of the blade shapes, ready to be inserted into mechanical design software (see the page on the 3D exports of the propeller).

2: Operating point of a fluid network

The operating point of an aeraulic or hydraulic fluid system is resolved by the intersection of two curves: the pressure loss curve of the network as a function of the flow rate, and the pressure curve of the pump as a function of the flow rate. The pressure losses of a network grow roughly as the square of the flow rate; the pressure of a propeller pump, for its part, decreases as the flow rate increases. The two curves cross at one point: the real flow rate of the system, with the corresponding pressure.

The characteristics of a pump are therefore edited in the form of a pressure curve, that is the pressure delta between upstream and downstream of the pump. The Mecaflux Pro3D software uses the data of this curve to resolve the operating point of a fluid network.

3: The export to Mecaflux Pro3D

The export tool to Pro3D exports the propeller, of the propeller pump or fan type with the fairing option checked, in the Mecaflux Pro3D pump format. You thus find the operating point of a network connected to the pump. A few conditions apply:

A window Export pump to Mecaflux Pro3D opens. It shows the nominal flow rate (in m³/h) and the nominal rotation speed of the propeller. In it, you set the flow rate range (minimum and maximum flow rate) over which the pump curve will be calculated. The button to export to Mecaflux Pro3D in .pomp format (pumps or fans) then writes the file. If the propeller cavitates at the nominal flow rate, Heliciel tells you: cavitation must be avoided before the export.

To go further, we can see the page on modelling a hydroelectric turbine, or check the strength of the blade before building the pump.