This function evaluates the finite line source solution. This solution gives the relation between the constant heat transfer rate (per unit length) injected by a group of line sources of finite length H1 buried at a distance D1 from a constant temperature surface (T=0) and the average temperature raise over a group of N2 lines of finite length H2 buried at a distance D2 from the constant temperature surface. The finite line source solution is defined by:
where ΔT1-2(t,r1->2,H1,D1,H2,D2,N2) is the temperature raise over lines in group 2 after a time t of constant heat injection, r1->2 is the list of distance between all pairs of lines in groups 1 and 2, N1->2 is the number of distances, Q' is the heat injection rate per unit length, ks is the soil thermal conductivity and hFLS is the finite line source solution.
The finite line source solution is given by:
where αs is the ground thermal diffusivity and erfint is the integral of the error function, defined in AixLib.Fluid.Geothermal.Borefields.BaseClasses.HeatTransfer.ThermalResponseFactors.finiteLineSource_erfint. The integral is solved numerically, with the integrand defined in AixLib.Fluid.Geothermal.Borefields.BaseClasses.HeatTransfer.ThermalResponseFactors.finiteLineSource_Integrand_Equivalent.
function finiteLineSource_Equivalent extends Modelica.Icons.Function; input Modelica.Units.SI.Time t "Time"; input Modelica.Units.SI.ThermalDiffusivity aSoi "Ground thermal diffusivity"; input Modelica.Units.SI.Distance dis[n_dis] "Radial distance between borehole axes"; input Integer wDis[n_dis] "Number of occurences of each distance"; input Modelica.Units.SI.Height len1 "Length of emitting boreholes"; input Modelica.Units.SI.Height burDep1 "Buried depth of emitting boreholes"; input Modelica.Units.SI.Height len2 "Length of receiving boreholes"; input Modelica.Units.SI.Height burDep2 "Buried depth of receiving boreholes"; input Integer nBor2 "Number of receiving boreholes"; input Integer n_dis "Number of unique distances"; input Boolean includeRealSource = true "True if contribution of real source is included"; input Boolean includeMirrorSource = true "True if contribution of mirror source is included"; output Real h_21 "Thermal response factor of borehole 1 on borehole 2"; end finiteLineSource_Equivalent;