modelPolynomialVolumetricEfficiency

Model describing volumetric efficiency based on polynomial approach

Extends from PartialVolumetricEfficiency (Based model used by all models describing volumetric efficiencies).

Information

This model contains a calculation procedure for volumetric 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, eigtht 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.

"Polynomial approaches" border="1" cellspacing="0" cellpadding="2" style="border-collapse:collapse;">
Reference Formula Refrigerants Validity ncompressor Validity Πpressure
DarrAndCrawford1992 ηvol = a1 + a2*n - a3*epsRef*(ρinlIse/ρinl-1) - a4*n*(ρinlIse/ρinl-1) R134a 40 - 75 3 - 10
Karlsson2007 ηvol = a1*Tinl*π + a2*π + a3 + a4*Tinl + a5*n + a6*n^2 R407c No information No information
KinarbEtAl2010 ηvol = a1 + a2*π Generic model Generic model Generic model
ZhouEtAl2010 ηvol = 1 + a1 - a2*π^(1/κ) Generic model Generic model Generic model
Li2013 ηvol = ηvolRef * (a1 + a2*(n/nref) + a3*(n/nref)^2) R22,R134a 30 - 120 4 - 12
HongtaoLaughmannEtAl2017 ηvol = a1 + a2*(n/nref) + a3*(n/nref)^2 + a4*π + a5*(n/nref)*π + a6*(n/nref)^2*π + a7*π^2 + a8*(n/nref)*π^2 + a9*(n/nref)^2*π^2 + a10*pout + a11*(n/nref)*pout + a12*(n/nref)^2*pout - a13*pinl - a14*(n/nref)*pinl - a15*(n/nref)^2*pinl + a16*pinl*pout + a17*(n/nref)*pinl*pout + a18*(n/nref)^2*pinl*pout + a19*(n/nref)^3*pinl*pout + a20*(n/nref)^4*pinl*pout - a21*pinl^2 - a22*(n/nref)*pinl^2 - a23*(n/nref)^2*pinl^2 - a24*(n/nref)^3*pinl^2 - a25*(n/nref)^4*pinl^2 Generic model Generic model Generic model
Koerner2017 ηvol = a1*π^b1 R410a 50 - 120 1 - 10
Engelpracht2017 ηvol = a1 + a2*((π-c1)/c2) + a3*((Tinl-c3)/c4)*((π-c1)/c2) + a4*((Tinl-c3)/c4) + a5*((n-c5)/c6) + a6*((n-c5)/c6)^2 Generic model 0 - 120 1 - 10

References

J.H. Darr and R.R. Crawford (1992): Modeling of an Automotive Air Conditioning Compressor Based on Experimental Data: ACRC Technical Report 14. Publisher: Air Conditioning and Refrigeration Center. College of Engineering. University of Illinois at Urbana-Champaign.

F. Karlsson (2007): Capacity Control of Residential Heat Pump Heating Systems. In: PhD thesis

R. Zhou, T. Zhang, J. Catano, J.T. Wen, G.J. Michna, Y. Peles, and M.K. Jensen, M. K. (2010): The steady-state modeling and optimization of a refrigeration system for high heat flux removal. In: Applied Thermal Engineering 30(16), S. 2347–2356

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

W. Li (2013): Simplified steady-state modeling for variable speed compressor. In: Applied Thermal Engineering 50(1), S. 318–326

Q. Hongtao, C.R. Laughman, D.J. Burns and S.A. Bortoff, (2017): Dynamic Characteristics of an R-410A Multi-split Variable Refrigerant Flow Air-conditioning System. In: IEA Heat Pump Conference 2017

D. Körner (2017): Development of dynamic compression heat pump models to evaluate promising refrigerants considering legal regulations. Master Thesis

M. Engelpracht (2017): Development of modular and scalable simulation models for heat pumps and chillers considering various refrigerants. Master Thesis

Parameters

TypeNameDefaultDescription
Modelling approach
Types.VolumetricPolynomialModelspolyModTypes.VolumetricPolynomialModels.Karlsson2007Chose predefined polynomial model for flow coefficient
Real[:]aMultiplication factors for each summand
Real[:]bExponents for each summand
IntegernTsize(a, 1)Number of terms used for the calculation procedure
Real[:]c{1}Coefficients used for correction factors if needed
Reference properties
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.EfficiencylamH (from PartialVolumetricEfficiency)Overall volumetric 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).