modelPolynomialEngineEfficiency
Extends from PartialEngineEfficiency (Based model used by all models describing engine efficiencies).
Information
This model contains a calculation procedure for engine efficiency models (for more information, please check out AixLib.Fluid.Movers.Compressors.BaseClasses.PartialCompression). The calculation procedures based on a polynomial approach are presented below.
Implemented approaches
Actually, four polynomial approaches are implemented in this package.
To add further calculation procedures, just add its name in AixLib.Fluid.Movers.Compressors.Utilities.Types
and expand the if-structure.
| Reference | Formula | Refrigerants |
Validity ncompressor
|
Validity Πpressure
|
|---|---|---|---|---|
| JahningEtAl2000 |
ηeng = a1 +
a2*exp(pInl)^b2
|
Generic model |
Generic model
|
Generic model
|
| DurprezEtAl2007 |
ηeng = a1 + a2*π + a3*π^2 + a4*π^3 + a5*π^4
+ a6*π^5 + a7*π^6
|
Generic model |
Generic model
|
Generic model
|
| KinarbEtAl2010 |
ηeng = a1 + a2*π + a3*π^2
|
Generic model |
Generic model
|
Generic model
|
| Engelpracht2017 |
ηeng = a1 + a2*π + a3*π^2 + a4*n*π + a5*n^2
+ a6*π^2*n + a7*π*n^2 + a8*n^3 + a9*π^2n^2 + a10*π*π^3 +
a11*n^4
|
Generic model |
0 - 120
|
1 - 10
|
References
I.D. Jähnig, D. Reindl and S.A. Klein, S. A. (2000): Semi-empirical method for representing domestic refrigerator/freezer compressor calorimeter test data.
M.-E Duprez, E. Dumont and M. Frère (2007): Modelling of reciprocating and scroll compressors. In: International Journal of Refrigeration 30(5), S. 873–886
E. Kinab, D. Marchio, P. Rivière and A. Zoughaib (2010): Reversible heat pump model for seasonal performance optimization. In: Energy and Buildings 42(12), S. 2269–2280
M. Engelpracht (2017): Development of modular and scalable simulation models for heat pumps and chillers considering various refrigerants. Master Thesis
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | useIseWor (from PartialEngineEfficiency) | false | = true, if isentropic work is used to compute compressor's power consumption |
| Modelling approach | |||
| Types.EnginePolynomialModels | polyMod | Types.EnginePolynomialModels.DurprezEtAl2007 | Chose predefined polynomial model for flow coefficient |
| Real[:] | a | Multiplication factors for each summand | |
| Real[:] | b | Exponents for each summand | |
| Integer | nT | size(a, 1) | Number of terms used for the calculation procedure |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Efficiency | epsRef (from PartialEfficiency) | Ratio of the real and the ideal displacement volume | |
| Modelica.Units.SI.Volume | VDis (from PartialEfficiency) | Displacement volume | |
| Real | piPre (from PartialEfficiency) | Ratio of compressor's outlet and inlet pressure | |
| Modelica.Units.SI.Frequency | rotSpe (from PartialEfficiency) | Compressor's current rotational speed | |
| Medium.ThermodynamicState | staInl (from PartialEfficiency) | Thermodynamic state at compressor's inlet | |
| Medium.ThermodynamicState | staOut (from PartialEfficiency) | Thermodynamic state at compressor's outlet | |
| Modelica.Units.SI.Temperature | TAmb (from PartialEfficiency) | Ambient temperature | |
| Modelica.Units.SI.Efficiency | etaEng (from PartialEngineEfficiency) | Overall engine efficiency | |
| Real[nT] | p | Array that contains all coefficients used for the calculation procedure | |
| Real[2] | corFac | Array of correction factors used if efficiency model proposed in literature differs from efficiency model defined in PartialCompressor model |
Revisions
- October 20, 2017, by Mirko Engelpracht:
First implementation (see issue 467).