AirConditioning Library 1.22 is part of Modelon's 2021.2 release. New versions of Modelon's libraries are sold and distributed directly from Modelon, as well as approved resellers.
Version 1.22 contains the changes described below.
Build 1 (2021-06-10)
- Major improvements for media using spline-based table lookup (SBTL):
- All functions from the media interface are implemented, so that SBTL media can replace Helmholtz-energy based media in any model without changes to that model.
- Added derivatives, so that tools can generate analytic Jacobians.
- Increased range where media can be used.
- Improved robustness and better test coverage.
- Restructuring to reduce code duplication.
- Added two system examples with and A/C cycle transiently changing to heat pump operation by reversing the refrigerant flow direction.
System examples are found in the AirConditioning.Examples.HeatPumpMode package and differ in the TXV configuration. Note that it is possible to compile these with analytic ODE Jacobian for improved simulation performance.
- Added a four-way valve to simplify the modeling of reversing refrigerant flow direction. This can be found at AirConditioning.Valves.FourPortsValve.
- Added options for initial value propagation through connectors.
With this option enabled, user can define pressure/enthalpy difference for initialization; and the components would automatically propagate and calculate the inlet and outlet values depending on upstream or downstream choice. This has been implemented within two-phase components and example system models are provided in InitialValuePropagation.
See General Instructions:Initialization for more information.
- Added initialization value for Kv for valves in cycle initialization records with default value calculated from high and low pressure.
analyticInverseTfromhparameter in the AirTransport and AirTemperature models to compute temperature for given specific enthalpy and vice versa.
- Added derivative to functions h_T and h_T_low in ThermoFluidPro.Media.IdealGases.Common.
- Corrected the derivative annotations in ThermoFluidPro.Media.Air.MoistAir and ThermoFluidPro.Media.Air.NoncondensingAir.
- Added example model to illustrate the usage of Analytic Jacobians in the component level Evaporator_SBTL_AnalyticalJacobians.
- Added example model to illustrate the usage of Analytic Jacobians in the system level TXVCycleOnOff_0_flow_SBTL_AnalyticalJacobians.
- Added example model to illustrate the usage of Analytic Jacobians in the system model with air path models VapourCycleWithCabin_SBTL_AnalyticalJacobians.
- Changed calibration factors in InternalHX from parameter to input.
Library structure changes
- The function ThermoFluidPro.CommonFunctions.LogMean and its derivative have been removed and these have been converted to Modelon.ThermoFluid.HeatExchangers.Functions.logMean and Modelon.ThermoFluid.HeatExchangers.Functions.logMean_der instead.