Modelon Library 4.1 is part of Modelon’s 2022.2 release.
- Added a compressor model TenCoefficientsCompressor parameterized by the 10 coefficients according to the AHRI-540 standard.
- Added a low fildeity model for a positive displacement compressor Modelon.ThermoFluid.LowFidelity.IsothermalDisplacementCompressor, parameterized by constant volumetric and isothermal efficiencies.
- In the existing positive displacement compressor model, Modelon.ThermoFluid.Compressors.PositiveDisplacementCompressor, added a compressor characteristic model that allow specifying constant volumetric, isentropic and mechanical efficiencies.
- Medium interface GenericMedium has been extended with a sub-package "Stagnation", including models and functions to facilitate more rigorous compressible flow calculations.
- Added equations of state for ideal gases by Walsh & Fletcher for gas turbine engine calculations including dependency on air - burned fuel ratio.
- In IdealGas and RealGas templates, the isentropicExponent function was modified to compute the property from density, velocity of sound and pressure. The result differs from the previous expression only for RealGas.
- Added a function heatCapacityRatio to return the ratios of specific heats, cp/cv. For ideal gases, results are identical to isentropicExponent.
- Added a function compressibilityFactor to HomogeneousMedium interface, and an implementation of it in IdealGas and RealGas templates.
Added Interpolation Methods
Additional interpolation methods have been added to 1D tables (e.g. ModelonTable1D, ModelonTable1Ds). Three new cubic Hermite spline methods have been added:
- Fritsch-Butland interpolation: Smooth interpolation by cubic Hermite splines such that y preserves the monotonicity and der(y) is continuous, also if extrapolated.
- Steffen interpolation: Smooth interpolation by cubic Hermite splines such that y preserves the monotonicity and der(y) is continuous, also if extrapolated.
- Modified Akima interpolation: Smooth interpolation by cubic Hermite splines such that der(y) is continuous, also if extrapolated. Additionally, overshoots and edge cases of the original Akima interpolation method are avoided.
- Corrected errors in calculation of static head in LiquidReceiver and PhaseSeparator.
- Added start attribute to variable p_sat in DistributedTwoPhase channel component.
- Corrected an incorrect derivative annotation on function Modelon.Media.Templates.RealGas.setState_pTX.
- Added additional interpolation options for 1D tables.
Conversion of User Libraries
User libraries will automatically be converted from version 4.0. These conversions are made using the included conversion script: Modelon/Resources/Scripts/Convert_to_4.1.mos.