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Table 2 Value ranges and statistical distributions of the input parameters for the sensitivity analysis
Parameter | Unit | Value range | Distribution | ||
|---|---|---|---|---|---|
Min | Reference | Max | |||
Measurements | |||||
\(L_{BHE}\) | m | 70 | 100 | 150 | Normal |
\(d_{BHE}\) | m | 0.12 | 0.152 | 0.2 | Normal |
\(d_{po}\) | m | 0.025 | 0.032 | 0.04 | Normal |
Pipe material | |||||
\(\lambda _{p}\) | \({{\textrm{W}}\,{\textrm{m}}^{-1}\,{\textrm{K}}^{-1}}\) | 0.4 | 0.4 | 2 | Normal |
Refrigerant | |||||
\(\rho _{rf}\) | \({{\mathrm{kg\,m}}^{-3}}\) | 960 | 1052 | 1195 | Normal |
\(c_{rf}\) | \({{\mathrm{J \, kg}}^{-1} \,{\textrm{K}}^{-1}}\) | 3050 | 3795 | 4250 | Normal |
\(\lambda _{rf}\) | \({{\textrm{W}}\,{\textrm{m}}^{-1}\,{\textrm{K}}^{-1}}\) | 0.44 | 0.48 | 0.57 | Normal |
\(\mu _{rf}\) | \({{\textrm{kg}}\,{\textrm{m}}^{-1}\,{\textrm{s}}^{-1}}\) | 0.0016 | 0.0052 | 0.0108 | Normal |
Grout | |||||
\(\lambda _{gr}\) | \({{\textrm{W}}\,{\textrm{m}}^{-1}\,{\textrm{K}}^{-1}}\) | 0.6 | 2 | 4 | Normal |
\(c_{vgr}\) | \({{\mathrm{kJ \, m}}^{-3} \, {\textrm{K}}^{-1}}\) | 1610 | 1910 | 2210 | Normal |
Subsurface | |||||
\(n_{Peff}\) | – | 0 | 0.125 | 0.25 | Uniform |
\(\lambda _{s}\) | \({{\textrm{W}}\,{\textrm{m}}^{-1}\,{\textrm{K}}^{-1}}\) | 1 | 2.5 | 5 | Normal |
\(c_{vs}\) | \({{\mathrm{kJ \, m}}^{-3} \, {\textrm{K}}^{-1}}\) | 500 | 1700 | 3800 | Normal |
\(t_{aqf}\) | –* | 0 | 0.25 | 1 | Uniform |
\(z_{aqf}\) | –* | 0 | 0.25 | 1 | Uniform |
Initial and boundary conditions | |||||
\({\dot{V}}_{rf}\) | \({{\textrm{m}}^3 \,{\textrm{s}}^{-1}}\) | \(2.39 \cdot 10^{-4}\) | \(7.4\cdot 10^{-4}\) | \(1.24\cdot 10^{-3}\) | Uniform |
Q | MWh | 7.2 | 18 | 28.8 | Normal |
\(v_f\) | \({{\mathrm{m \, s}}^{-1}}\) | 0 | \(4.75 \cdot 10^{-7}\) | \(3\cdot 10^{-5}\) | Normal |
\(\Delta T_{geo}\) | \({{\mathrm{K \, m}}^{-1}}\) | 0 | 0.032 | 0.045 | Normal |
\(T_{geo}\) ** | K | − 4.64 | 0 | 4.44 | Normal |