Note: this link has been obsoleted by the GunnsGasFan link. We recommend using that link instead. This link has been deprecated and gives deprecated warnings during compilation and run-time initialization.

This extends GunnsFluidPotential with a simplified model of a fluid impeller. This is basically GunnsGasFan without the impeller performance curve, power & torque model. Pressure created does not depend on flow rate, so this is equivalent to a GunnsGasFan with a flat performance curve, i.e. its curve coefficients 1-5 all equal to zero. It retains the Affinity Laws governing the effect of spin speed and inlet density on pressure.

Use this link in lieu of the more complicated GunnsGasFan or GunnsLiquidCentrifugalPump when you need a more idealized impeller model and do not need to send torque back to a dynamic motor model. This can be used in either gas or liquid systems, but it lacks a liquid cavitation model.

This link should not be used for positive displacement (constant-volume) pumps such as pistons, etc. For those types of pumps, use the appropriate displacement pump link instead.

This link models isentropic expansion and convection heat transfer between the fluid and the fan/pipe wall, similar to other pipe & HX links. This link does not modify the mixture of the fluid passing through it.

This link has the same connection rules as GunnsFluidPotential. Multiple impellers can be staged in any combination, either in parallel or series, and in sympathetic or opposing directions. However, they do not interact with each other in a realistic way.

Port Connection Rules (These are limitations on the port connection to nodes that the link enforces in run-time):

• Same as GunnsFluidConductor.

Other Rules (These are extra rules you should always try to follow):

• Same as GunnsFluidPotential.

Configuration Data Parameters:

• maxConductivity: Same as GunnsFluidPotential.
• expansionScaleFactor: Same as GunnsFluidConductor.
• referenceDensity: Same as GunnsGasFan.
• referenceSpeed: Same as GunnsGasFan.
• thermalLength: Same as GunnsFluidValve.
• thermalDiameter: Same as GunnsFluidValve.
• surfaceRoughness: Same as GunnsFluidValve.

Input Data Parameters:

• malfBlockageFlag: Same as GunnsFluidConductor.
• malfBlockageValue: Same as GunnsFluidConductor.
• sourcePressure (default = 0, must >= 0): This defines the pressure the impeller will create at the referenceDensity and referenceSpeed values. Pressure varies with speeed and density by the fan Affinity Laws.
• motorSpeed: Same as GunnsGasFan.
• wallTemperature: Same as GunnsFluidValve.

• This link is avoids most of the potential stability problems with GunnsGasFan, but it is still susceptible to the negative inlet pressure problem (see the Common Problems in GunnsGasFan).

• N/A