Positive Displacement Compressor

Positive Displacement compressors/blowers can be considered to provide a fixed flow for steady state analysis. The positive displacement compressor/blower allows for a fixed flow to be defined in a straightforward manner.

To model a positive displacement compressor/blower, select the Positive Displacement option on the Compressor Model tab of the Compressor/Fan Properties window.

Parameter

Volumetric Flow Rate - Fix the volumetric flow rate at the inlet of the compressor/blower. Due to compressibility effects, the outlet volumetric flow rate may differ.
Mass Flow Rate - Fix the mass flow rate through the compressor/blower.

Fixed Condition

Fixed Flow Rate - The value and unit of the fixed flow amount.
Nominal Efficiency - A fixed efficiency, useful to calculate power requirements.

The Compressor/Fan Properties window is shown with the Compressor model set to Positive Displacement Compressor.

Figure 1: Positive Displacement Compressor/Blower Model