Compressor models

class PythonModel.compressors.ReciprocatingCompressor(parameters)

Bases: object

Object for reciprocating compressor model based on Jin (2002): H. Jin. Parameter estimation based models of water source heat pumps. PhD Thesis. Oklahoma State University. Stillwater, Oklahoma, USA. 2012.

Parameters:
  • pisDis – Piston displacement (m3/s).
  • cleFac – Clearance factor (-).
  • etaEle – Electro-mechanical efficiency (-).
  • PLos – Constant part of the power losses (W).
  • pDro – Pressure drop at compressor suction and discharge (Pa).
  • dTSup – Degree of superheating (K).
get_DischargePressure(pCon)

Evaluate the discharge pressure (Pa).

Parameters:pCon – Condensing pressure (Pa).
Returns:Discharge pressure (Pa).
Usage: Type
>>> com = ReciprocatingCompressor([0.00162, 0.069, 0.696, 100.0, 99.29e3, 9.82])
>>> '%.1f' % com.get_DischargePressure(1.879e6)
'1978290.0'
get_Power(vSuc, ref, pDis, pSuc, TSuc, **kargs)

Evaluate the power input to the compressor.

Parameters:
  • vSuv – Suction specific volume (m3/kg).
  • ref – Refrigerant model.
  • pDis – Discharge pressure (Pa).
  • pSuc – Suction pressure (Pa).
  • TSuc – Suction temperature (K).
Returns:

Power input to the compressor (W).
Usage: Type
>>> import refrigerants
>>> ref = refrigerants.R410A()
>>> com = ReciprocatingCompressor([0.00162, 0.069, 0.696, 100.0, 99.29e3, 9.82])
>>> '%.2f' % com.get_Power(0.0288, ref, 1978290.0, 983710.0, 292.97)
'1765.63'
get_RefrigerantMassFlowRate(vSuc, ref, pDis, pSuc, TSuc, **kargs)

Evaluate the refrigerant mass flow rate.

Parameters:
  • vSuv – Suction specific volume (m3/kg).
  • ref – Refrigerant model.
  • pDis – Discharge pressure (Pa).
  • pSuc – Suction pressure (Pa).
  • TSuc – Suction temperature (K).
Returns:

Refrigerant mass flow rate (kg/s).
Usage: Type
>>> import refrigerants
>>> ref = refrigerants.R410A()
>>> com = ReciprocatingCompressor([0.00162, 0.069, 0.696, 100.0, 99.29e3, 9.82])
>>> '%.8f' % com.get_RefrigerantMassFlowRate(0.0288, ref, 1978290.0, 983710.0, 292.97)
'0.05358166'
get_SuctionPressure(pEva)

Evaluate the suction pressure.

Parameters:pEva – Evaporating pressure (Pa).
Returns:Suction pressure (Pa).
Usage: Type
>>> com = ReciprocatingCompressor([0.00162, 0.069, 0.696, 100.0, 99.29e3, 9.82])
>>> '%.1f' % com.get_SuctionPressure(1.083e6)
'983710.0'
get_SuctionTemperature(TEva)

Evaluate the suction temperature.

Parameters:TEva – Evaporating temperature (K).
Returns:Suction temperature (K).
Usage: Type
>>> com = ReciprocatingCompressor([0.00162, 0.069, 0.696, 100.0, 99.29e3, 9.82])
>>> '%.2f' % com.get_SuctionTemperature(283.15)
'292.97'
initialGuessParameters(Q_nominal, P_nominal, TSou_nominal, TLoa_nominal, ref, CoolingMode)

Initialize guess parameters for calibration of the heat pump model.

Parameters:
  • Q_nominal – Nominal heat pump capacity (W).
  • P_nominal – Nominal power input (W).
  • TSou_nominal – Source-side water temperature at nominal conditions (K).
  • TLoa_nominal – Load-side water temperature at nominal conditions (K).
  • ref – Refrigerant model.
  • CoolingMode – Boolean, True if heat pump is in cooling mode.
Returns:

A list of parameters to the compressor model, a list of tuples of the bounds of the parameters (min, max) for the calibration routine.
modelicaModelPath()
Returns the full path to the compressor model in the Buildings
library.
Returns:Full path to the compressor model in the IBPSA library.
Usage: Type
>>> com = ReciprocatingCompressor([0.00162, 0.069, 0.696, 100.0, 99.29e3, 9.82])
>>> com.modelicaModelPath()
'IBPSA.Fluid.HeatPumps.Compressors.ReciprocatingCompressor'
printParameters()

Prints the value of the model parameters.

reinitializeParameters(parameters)

Reinitializes the compressor using new parameters.

Parameters:
  • pisDis – Piston displacement (m3/s).
  • cleFac – Clearance factor (-).
  • etaEle – Electro-mechanical efficiency (-).
  • PLos – Constant part of the power losses (W).
  • pDro – Pressure drop at compressor suction and discharge (Pa).
  • dTSup – Degree of superheating (K).
class PythonModel.compressors.ScrollCompressor(parameters)

Bases: object

Object for scroll compressor model based on Jin (2002): H. Jin. Parameter estimation based models of water source heat pumps. PhD Thesis. Oklahoma State University. Stillwater, Oklahoma, USA. 2012.

Parameters:
  • volRat – Volume ratio (-).
  • v_flow – Nominal Volume flow rate (m3/s).
  • leaCoe – LEakage coefficient (kg/s).
  • etaEle – Electro-mechanical efficiency (-).
  • PLos – Constant part of the power losses (W).
  • dTSup – Degree of superheating (K).
get_DischargePressure(pCon)

Evaluate the discharge pressure (Pa).

Parameters:pCon – Condensing pressure (Pa).
Returns:Discharge pressure (Pa).
Usage: Type
>>> com = ScrollCompressor([2.362, 0.00287, 0.0041, 0.922, 398.7, 6.49])
>>> '%.1f' % com.get_DischargePressure(1.879e6)
'1879000.0'
get_Power(vSuc, ref, pDis, pSuc, TSuc)

Evaluate the power input to the compressor.

Parameters:
  • vSuv – Suction specific volume (m3/kg).
  • ref – Refrigerant model.
  • pDis – Discharge pressure (Pa).
  • pSuc – Suction pressure (Pa).
  • TSuc – Suction temperature (K).
Returns:

Power input to the compressor (W).
Usage: Type
>>> import refrigerants
>>> ref = refrigerants.R410A()
>>> com = ScrollCompressor([2.362, 0.00287, 0.0041, 0.922, 398.7, 6.49])
>>> '%.2f' % com.get_Power(0.025, ref, 1.879e6, 1.083e6, 289.64)
'2940.26'
get_RefrigerantMassFlowRate(vSuc, pDis, pSuc, **kargs)

Evaluate the refrigerant mass flow rate.

Parameters:
  • vSuv – Suction specific volume (m3/kg).
  • pDis – Discharge pressure (Pa).
  • pSuc – Suction pressure (Pa).
  • TSuc – Suction temperature (K).
Returns:

Refrigerant mass flow rate (kg/s).
Usage: Type
>>> com = ScrollCompressor([2.362, 0.00287, 0.0041, 0.922, 398.7, 6.49])
>>> '%.6f' % com.get_RefrigerantMassFlowRate(0.025, 1.879e6, 1.083e6)
'0.107687'
get_SuctionPressure(pEva)

Evaluate the suction pressure.

Parameters:pEva – Evaporating pressure (Pa).
Returns:Suction pressure (Pa).
Usage: Type
>>> com = ScrollCompressor([2.362, 0.00287, 0.0041, 0.922, 398.7, 6.49])
>>> '%.1f' % com.get_SuctionPressure(1.083e6)
'1083000.0'
get_SuctionTemperature(TEva)

Evaluate the suction temperature.

Parameters:TEva – Evaporating temperature (K).
Returns:Suction temperature (K).
Usage: Type
>>> com = ScrollCompressor([2.362, 0.00287, 0.0041, 0.922, 398.7, 6.49])
>>> '%.2f' % com.get_SuctionTemperature(283.15)
'289.64'
initialGuessParameters(Q_nominal, P_nominal, TSou_nominal, TLoa_nominal, ref, CoolingMode)

Initialize guess parameters for calibration of the heat pump model.

Parameters:
  • Q_nominal – Nominal heat pump capacity (W).
  • P_nominal – Nominal power input (W).
  • TSou_nominal – Source-side water temperature at nominal conditions (K).
  • TLoa_nominal – Load-side water temperature at nominal conditions (K).
  • ref – Refrigerant model.
  • CoolingMode – Boolean, True if heat pump is in cooling mode.
Returns:

A list of parameters to the compressor model, a list of tuples of the bounds of the parameters (min, max) for the calibration routine.
modelicaModelPath()
Returns the full path to the compressor model in the Buildings
library.
Returns:Full path to the compressor model in the IBPSA library.
Usage: Type
>>> com = ScrollCompressor([2.362, 0.00287, 0.0041, 0.922, 398.7, 6.49])
>>> com.modelicaModelPath()
'IBPSA.Fluid.HeatPumps.Compressors.ScrollCompressor'
printParameters()

Prints the value of the model parameters.

reinitializeParameters(parameters)

Reinitializes the compressor using new parameters.

Parameters:
  • volRat – Volume ratio (-).
  • v_flow – Nominal Volume flow rate (m3/s).
  • leaCoe – LEakage coefficient (kg/s).
  • etaEle – Electro-mechanical efficiency (-).
  • PLos – Constant part of the power losses (W).
  • dTSup – Degree of superheating (K).
set_ModelicaParameters(simulator, suffix='')

Set parameter values for simulation in dymola.

Parameters:
  • simulator – Simulator object (BuildinsPy)
  • suffix – String to add at the end of parameter names.
Returns:

Simulator object (BuildingsPy)