Release Notes for Heat Exchanger Library 2.1
Heat Exchanger Library 2.1 is part of Modelon’s 2018.1 release.
New versions of Modelon libraries are sold and distributed directly from Modelon, as well as approved resellers.
- A new air side variant, StandAloneAirFlowLumpedDp, has been added for flattube heat exchangers. It contains a simplified pressure drop correlation, computing only a single channel pressure loss, instead of distributed loss correlations for all parallel air channel segments. This improves simulation performance and is recommended for homogeneous mass flow boundary conditions. The option cannot be used for heat exchangers simulated in a stack.
- A new dynamic testbench model, CoolerTransientsInputOnTable, with table based transient boundary conditions on file, was added for cross-flow (flat-tube) heat exchangers.
- An added experiment model for the heat transfer calibration workflow: EvaporatorCalibration.
- An added experiment model of a stack which applies the same conditions as found in TwoHXs. The new TwoHXs_AdditionalGrids example illustrates refinement of the flow segmentation by adding additional points in y and z directions. The example has 3 additional grid points in both, y and z direction.
- LiquidGasFinPlainCounter is a new liquid-gas counter-flow heat exchanger with a plain liquid side plate surface and finned gas side, used e.g. as water cooled charge air cooler.
- In testbench models, the constraining class of all signal source blocks is changed to SO, the base class for signal sources in the MSL in order to support flexible replacement, when extending from the template.
- Initial value parameters are added to Sources.Lumped component. In a mass flow source the initial pressure and in a pressure source the initial mass flow rate are intended to improve convergence of steady-state initialization of component tests.
- Name changes in summary records to follow naming convention
- The fin pressure drop correlations based on fanning friction factor, i.e. ReynoldsPowerLaw, KimBullard, ChangHsu and ManglikBergles, have been found to give incorrect results when computing mass flow rate from pressure drop in discretized gas channels. This affects the pressure drop on the hot side of charge air coolers, but not on the ambient side. This was fixed and the original correlation is kept as a deprecated class for backwards compatibility. Existing user models will automatically be converted to use the deprecated class with the included conversion script.
- The ChangHsu correlation for air side pressure drops was corrected for low Reynolds numbers below 150. Existing models using that correlation are converted to the deprecated class with the included conversion script in order to retain calibrated behavior.
Heat Exchanger Library 2.1 is based on Modelon Base Library 3.1 and Modelica Standard Library 3.2.2.