Sensible energy storage in aquifers: 2. Field experiments and comparison with theoretical results

Abstract

Ten successive in situ experimental investigations of hot water storage by a single well and a pair of wells (doublet) were conducted in 1976–1977 at Bonnaud, Jura, in a confined aquifer 2.5 m thick. The injected volumes ranged from 500–1700 m3. Temperature profiles were measured daily in 12 boreholes distributed along two perpendicular axes within 13 m of the injection well. Individual temperatures were measured by ten thermistors placed in the caprock. The results are discussed and used to calibrate two mathematical models. An axisymmetric model allows the calibration of average values of the parameters, while a three‐dimensional model is used to determine their spatial variation in the horizontal plane. The latter model leads to the identification of a nonhomogeneous transmissibility field which fully accounts for both hydraulic and thermal contour curves. The models, which were matched against particular experiments, proved accurate when simulating other periods. Evidence is given of the importance to the recovery ratio of thermal dispersion in the aquifer and of the water content of the caprock. In a final section, experimental results of single well storage at Bonnaud, Campuget, and Auburn are compared with general type curves derived in the companion paper. They prove to yield adequate predictions of water temperature during the production phases.