modelCompressor_EN12900
Compressor model according to standard EN12900
Information
The Compressor_EN12900 model represents the compression of a fluid in a scroll compressor according to standard EN12900. It is a lumped model. It is characterized by two flow connector for the fluid inlet and outlet and by a mechanical connector for the connection with the electric driver.
The assumptions for this model are:
- No dynamics ( it is considered negligible when compared to the one characterizing the heat exchanger).
- No thermal energy losses to the environment
- Mass flow and consumed power are calculated with a polynoms as a function of the saturation temperature of the corresponding inlet and outlet temperature
Modelling options
In the General tab the following option is availabe:
- CPmodel: it allows to select one of the different available scroll compressor characteristics.
Polynomial expression
In the EN12900 standard, the compressor consumption and the mass flow rate are expressed as a function of the evaporation and condensation temperatures with the following equations:
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.SIunits.Frequency | N_rot | 50 | Compressor frequency |
| Initialization | |||
| Modelica.SIunits.MassFlowRate | M_dot_start | 0.02 | Nominal Mass flow rate |
| Modelica.SIunits.Pressure | p_su_start | 2.339e5 | Inlet pressure start value |
| Modelica.SIunits.Pressure | p_ex_start | 1.77175e6 | Outlet pressure start value |
| Modelica.SIunits.Temperature | T_su_start | 293.15 | Inlet temperature start value |
| Medium.SpecificEnthalpy | h_su_start | Medium.specificEnthalpy_pT(p_su_start, T_su_start) | Inlet enthalpy start value |
| Medium.SpecificEnthalpy | h_ex_start | Medium.specificEnthalpy_pT(p_ex_start, Medium.saturationTemperature(p_ex_start) + 50) | Outlet enthalpy start value |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Interfaces.Fluid.FlangeA | InFlow | ||
| Interfaces.Fluid.FlangeB | OutFlow |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Medium.ThermodynamicState | vaporIn | Thermodynamic state of the fluid at the inlet | |
| Medium.ThermodynamicState | vaporOut | Thermodynamic state of the fluid at the outlet - isentropic | |
| Real | epsilon_s | Isentropic Efficiency | |
| Real | epsilon_v | Volumetric efficiency | |
| Modelica.SIunits.Volume | Vs | Swept Volume | |
| Real | rpm | ||
| Modelica.SIunits.Power | W_dot | ||
| Modelica.SIunits.VolumeFlowRate | V_dot_su | ||
| Modelica.SIunits.MassFlowRate | M_dot | ||
| Medium.Density | rho_su | ||
| Medium.SpecificEntropy | s_su | ||
| Medium.SpecificEnthalpy | h_su | ||
| Medium.SpecificEnthalpy | h_ex | ||
| Medium.AbsolutePressure | p_su | ||
| Medium.AbsolutePressure | p_ex | ||
| Medium.SpecificEnthalpy | h_ex_s | ||
| Medium.Temperature | T_cd | ||
| Medium.Temperature | T_ev | ||
| Real[3] | results |
Contents
| Name | Description |
|---|---|
| Medium | |
| CPmodel |