Pump Sizing

The Centrifugal (Rotodynamic) Pump Model offers the option of Sizing a pump. By entering either a volumetric of mass flow rate, the total developed pressure is calculated and displayed in the Pump Summary section of the Output Window . By inputting a flow at a pump, determining the pump size requirements is straightforward. The Walk Through Examples have an example of using AFT Fathom to size a pump.

Pump Sizing with a Flow Control Valve

Using the sizing feature on a pump (fixing the flow rate) with a Flow Control Valve (which also fixes flow rate) downstream results in a Reference Pressure error - the system no longer has a unique solution. While the pump is being sized, the control valve must be temporarily defined as a Constant Pressure Drop Control Valve to avoid these errors. Read more about this in Role of Pressure Junctions - Detailed Discussion.

Suggest Pump

Once you have sized a pump you can use Suggest Pump, opened from Library Menu > Suggest Pump or the Output Toolbar, to find an actual pump that meets the requirements.

The Suggest Pump window allows you to specify search criteria and to select the libraries you want to search. Search criteria includes pump head, NPSH and BEP proximity. You can sort the pumps by proximity to operating head, BEP or alphabetically.

Once one or more pumps that meet your criteria have been identified, you can quickly view a composite curve for a pump by selecting it in the table and clicking the Show Pump Curve button.

In addition, you can pass operating point data to Internet hosted pump supplier websites which use Intelliquip™ Selector.

For an example of pump sizing in Fathom, see the "Sizing a Pump" example in the Fathom Example Help file.