modelPumpMech
Centrifugal pump with mechanical connector for the shaft
Extends from BaseClasses.PumpBase (Base model for centrifugal pumps), Icons.Water.PumpMech.
Information
This model describes a centrifugal pump (or a group of Np pumps in parallel) with a mechanical rotational connector for the shaft, to be used when the pump drive has to be modelled explicitly. In the case of Np pumps in parallel, the mechanical connector is relative to a single pump.
The model extends PumpBase
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Integer | Np0 (from PumpBase) | 1 | Nominal number of pumps in parallel |
| SI.Volume | V (from PumpBase) | 0 | Pump Internal Volume |
| Boolean | CheckValve (from PumpBase) | false | Reverse flow stopped |
| Boolean | allowFlowReversal (from PumpBase) | system.allowFlowReversal | = true to allow flow reversal, false restricts to design direction |
| SI.Acceleration | g (from PumpBase) | Modelica.Constants.g_n | |
| SI.VolumeFlowRate | q_single0 (from PumpBase) | w0/(Np0*rho0) | Nominal volume flow rate (single pump) |
| SI.Height | head0 (from PumpBase) | dp0/(rho0*g) | Nominal pump head |
| Real | d_head_dq_0 (from PumpBase) | (flowCharacteristic(q_single0*1.05) - flowCharacteristic(q_single0*0.95))/(q_single0*0.1) | Approximate derivative of flow characteristic w.r.t. volume flow |
| Real | d_head_dn_0 (from PumpBase) | 2/n0*head0 - q_single0/n0*d_head_dq_0 | Approximate derivative of the flow characteristic w.r.t. rotational speed |
| SI.Power | W_eps (from PumpBase) | 1e-8 | Small coefficient to avoid numerical singularities |
| NonSI.AngularVelocity_rpm | n_eps (from PumpBase) | 1e-6 | |
| Characteristics | |||
| Boolean | usePowerCharacteristic (from PumpBase) | false | Use powerCharacteristic (vs. efficiencyCharacteristic) |
| Units.LiquidDensity | rho0 (from PumpBase) | 1000 | Nominal Liquid Density |
| NonSI.AngularVelocity_rpm | n0 (from PumpBase) | Nominal rotational speed | |
| Medium.MassFlowRate | w0 (from PumpBase) | Nominal mass flow rate | |
| SI.Pressure | dp0 (from PumpBase) | Nominal pressure increase | |
| External inputs | |||
| Boolean | use_in_Np (from PumpBase) | false | Use connector input for the pressure |
| Initialisation | |||
| Medium.MassFlowRate | wstart (from PumpBase) | w0 | Mass Flow Rate Start Value |
| Medium.SpecificEnthalpy | hstart (from PumpBase) | 1e5 | Specific Enthalpy Start Value |
| Choices.Init.Options | initOpt (from PumpBase) | system.initOpt | Initialisation option |
| Boolean | noInitialPressure (from PumpBase) | false | Remove initial equation on pressure |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| FlangeA | infl (from PumpBase) | ||
| FlangeB | outfl (from PumpBase) | ||
| Modelica.Blocks.Interfaces.IntegerInput | in_Np (from PumpBase) | Number of parallel pumps | |
| Modelica.Mechanics.Rotational.Interfaces.Flange_a | MechPort |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Medium.ThermodynamicState | inletFluidState (from PumpBase) | Thermodynamic state of the fluid at the inlet | |
| ThermoPower.System | system (from PumpBase) | System wide properties | |
| Medium.MassFlowRate | w_single (from PumpBase) | Mass flow rate (single pump) | |
| Medium.MassFlowRate | w (from PumpBase) | Np*w_single | Mass flow rate (total) |
| SI.VolumeFlowRate | q_single (from PumpBase) | Volume flow rate (single pump) | |
| SI.VolumeFlowRate | q (from PumpBase) | Np*q_single | Volume flow rate (total) |
| SI.PressureDifference | dp (from PumpBase) | Outlet pressure minus inlet pressure | |
| SI.Height | head (from PumpBase) | Pump head | |
| Medium.SpecificEnthalpy | h (from PumpBase) | Fluid specific enthalpy | |
| Medium.SpecificEnthalpy | hin (from PumpBase) | Enthalpy of entering fluid | |
| Medium.SpecificEnthalpy | hout (from PumpBase) | Enthalpy of outgoing fluid | |
| Units.LiquidDensity | rho (from PumpBase) | Liquid density | |
| Medium.Temperature | Tin (from PumpBase) | Liquid inlet temperature | |
| NonSI.AngularVelocity_rpm | n (from PumpBase) | Shaft r.p.m. | |
| Integer | Np (from PumpBase) | Number of pumps in parallel | |
| SI.Power | W_single (from PumpBase) | Power Consumption (single pump) | |
| SI.Power | W (from PumpBase) | Np*W_single | Power Consumption (total) |
| SI.Power | Qloss (from PumpBase) | 0 | Heat loss (single pump) |
| SI.PerUnit | eta (from PumpBase) | Pump efficiency | |
| SI.PerUnit | s (from PumpBase) | Auxiliary non-dimensional variable | |
| SI.Angle | phi | Shaft angle | |
| SI.AngularVelocity | omega | Shaft angular velocity |
Revisions
- 5 Jul 2004
by Francesco Casella:
Model restructured by using inheritance. Adapted to Modelica.Media. - 15 Jan 2004
by Francesco Schiavo:
ThermalCapacity and CheckValve added. - 15 Dec 2003
by Francesco Schiavo:
First release.