24 June 2014

A NEW APPROACH TO THE STUDY OF THE HYDROTHERMODYNAMIC SYSTEM “GROUND – BOREHOLE HEAT EXCHANGER – GROUND SOURCE HEAT PUMP”


ncreasing energy efficiency of the ground source heat pump (GSHP) systems is an important task for further development and implementation of this renewable energy technology for industrial and domestic heating and cooling. Achieving the higher efficiency, in
its turn, requires insight into thermodynamic interaction of all elements of GSHP systems.
The presented in the paper mathematical model of a strongly non-equilibrium thermodynamic
systems G – BHE – GSHP has been elaborated to describe the energy exchange between the ground, BHE and evaporator of GSHP. Based on this model a stationary problem of such
system operation has been solved. In particular, it is shown that the stationary energy exchange processes in the G – U-tube BHE – HP system is characterized by a unique
dimensionless parameter – the ratio of the thermal conductivity of the ground and brine. For a stationary case a one-parameter universal dependence of the amount of energy extracted
from the ground using U-tube BHE, which is essentially non-linear in length, was obtained. The physical interpretation of the received results is provided.