Fig. 1. Design process of the vertical-type ground loop heat exchanger.
Fig. 2. Variation rate of GLHX length as a function of distance between boreholes.
Fig. 3. Variation rate of GLHX length as a function of radial pipe placement.
Fig. 4. Variation rate of GLHX length as a function of thermal conductivity.
Fig. 5. Variation rate of GLHX length as a function off low rate.
Fig. 6. Structure of a vertical-type GLHX.
Fig. 7. Temperature variation in TRT test.
Fig. 8. Thermal conductivity as a function of HDPE pipe conductivity.
Fig. 9. Thermal conductivity as a function of grout conductivity.
Fig. 10. Thermal conductivity as a function of ground conductivity.
Table 1. Design parameters
Table 2. Variation rate of GLHX length according to parameter's property
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