Function for Nusselt number in horizontal window cavity. The computation is according to TARCOG 2006, except that this implementation computes the Nusselt number as a function that is differentiable in the temperatures.
TARCOG 2006: Carli, Inc., TARCOG: Mathematical models for calculation of thermal performance of glazing systems with our without shading devices, Technical Report, Oct. 17, 2006.
function nusseltHorizontalCavityEnhanced extends Modelica.Icons.Function; input Buildings.HeatTransfer.Data.Gases.Generic gas "Thermophysical properties of gas fill" annotation( choicesAllMatching = true); input Real Ra(min = 0) "Rayleigh number"; input Modelica.Units.SI.Temperature T_m "Temperature used for thermophysical properties"; input Modelica.Units.SI.TemperatureDifference dT "Temperature difference used to compute q_flow = h*dT"; input Modelica.Units.SI.Angle til "Window tilt"; input Real cosTil(min = 0) "Cosine of the window tilt"; output Real Nu(min = 0) "Nusselt number"; end nusseltHorizontalCavityEnhanced;