Pumps are commonly used the transfer of liquid. The pump unit operation has one inlet and one outlet.
Either the absolute outlet pressure or the pressure increase must be specified. The outlet temperature is calculated from an energy balance. Either the power consumption or the pump efficiency must be specified. Power consumption and pump efficiency are related for an incompressible fluid by:
where L is the total liquid flow in m3/s, η denotes the efficiency of the pump and W the power adsorbed in J/s.
Power consumption can be specified directly or as an energy inlet stream.
If power consumption is not specified via an energy inlet stream, an energy outlet stream can be connected that will receive a value for the power consumed by the compressor.
The total liquid flow is taken as the total flow. If phases other than liquid phases are present, a warning is produced. The total volumetric flow is determined from the total molar flow multiplied by the average molar liquid volume; vapor phases are ignored in volume determination and the unit will fail in case the feed only contains vapor.
Volume is determined using the thermodynamic that apply to the inlet port.
For a gas flow, use a compressor unit operation.