modelPowerIsentropicEfficiency

Model describing flow isentropic efficiency on power approach

Extends from PartialIsentropicEfficiency (Based model used by all models describing isentropic efficiencies).

Information

This model contains a calculation procedure for isentropic efficiency models (for more information, please check out AixLib.Fluid.Movers.Compressors.BaseClasses.PartialCompression). The calculation procedures based on a power approach are presented below.

Implemented approaches

Actually, one power approache is 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.

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Reference Formula Refrigerants Validity ncompressor Validity Πpressure
MendozaMirandaEtAl2016 ηise = a1 * π^b1 * (nref/n)^b2 * (n^3*Vdis/dhise^1.5)^b3 * (1/((Tinl+ToutIse)/2-Tout))^b4 R134a,R450a,R1324yf,R1234ze(E) 0 - 50 1 - 6

References

J.M. Mendoza-Miranda, A. Mota-Babiloni, J.J. Ramírez-Minguela, V.D. Muñoz-Carpio, M. Carrera-Rodríguez, J. Navarro-Esbrí and C. Salazar-Hernández (2016): Comparative evaluation of R1234yf, R1234ze(E) and R450A as alternatives to R134a in a variable speed reciprocating compressor. In: Energy 114, S. 753–766

Parameters

TypeNameDefaultDescription
Modelling approach
Types.IsentropicPowerModelspowModTypes.IsentropicPowerModels.MendozaMirandaEtAl2016Chose predefined power model for flow coefficient
RealaMultiplication factor for generic power approach
Real[:]bExponents for each multiplier
IntegernTsize(b, 1)Number of terms used for the calculation procedure
Reference properties
Modelica.Units.SI.MolarMassMRef0.1Reference molar wheight
Modelica.Units.SI.FrequencyrotSpeRef9.334Reference rotational speed

Components

TypeNameDefaultDescription
Modelica.Units.SI.EfficiencyepsRef (from PartialEfficiency)Ratio of the real and the ideal displacement volume
Modelica.Units.SI.VolumeVDis (from PartialEfficiency)Displacement volume
RealpiPre (from PartialEfficiency)Ratio of compressor's outlet and inlet pressure
Modelica.Units.SI.FrequencyrotSpe (from PartialEfficiency)Compressor's current rotational speed
Medium.ThermodynamicStatestaInl (from PartialEfficiency)Thermodynamic state at compressor's inlet
Medium.ThermodynamicStatestaOut (from PartialEfficiency)Thermodynamic state at compressor's outlet
Modelica.Units.SI.TemperatureTAmb (from PartialEfficiency)Ambient temperature
Modelica.Units.SI.EfficiencyetaIse (from PartialIsentropicEfficiency)Overall isentropic efficiency
Real[nT]pArray that contains all coefficients used for the calculation procedure
Real[2]corFacArray 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).