.Buildings.Fluid.Storage.Ice.BaseClasses.calculateLMTDStar

Information

This subroutine calculates the log mean temperature difference for the detailed ice storage unit. The temperature difference is non-dimensionalized using a nominal temperature difference of 10 Kelvin. This value must be used when obtaining the curve fit coefficients.

The log mean temperature difference is calculated using

T_lmtd^* = T_lmtd/T_nom

T_lmtd = (T_in - T_out)/ln((T_in - T_fre)/(T_out - T_fre))

where T_in is the inlet temperature, T_out is the outlet temperature, T_fre is the freezing temperature and T_nom is a nominal temperature difference of 10 Kelvin.

Interface

function calculateLMTDStar
  extends Modelica.Icons.Function;
  input Modelica.Units.SI.Temperature TIn "Inlet temperature";
  input Modelica.Units.SI.Temperature TOut "Outlet temperature";
  input Modelica.Units.SI.Temperature TFre = 273.15 "Freezing temperature of water or the latent energy storage material";
  input Modelica.Units.SI.TemperatureDifference dT_nominal = 10 "Nominal temperature difference";
  output Real lmtd "Normalized LMTD";
end calculateLMTDStar;

Revisions

• December 8, 2021, by Yangyang Fu:
  First implementation.