Volume 55

Exploring the Maximum Heat Extraction Potential of Super Long Gravity Heat Pipes in Hot Dry Rock Geothermal Reservoirs Dongxi Liu, Haiyan Lei, Chuanshan Dai

Abstract

Extracting heat from a deep geothermal reservoir in a clean and efficient manner has always posed a significant challenge in geothermal exploration. This paper presents a numerical study of the heat extraction performance of a perfect super-long gravity heat pipe (SLGHP) under the assumptions of either an infinitely large heat transfer coefficient inside the SLGHP or a constant phase change temperature throughout the SLGHP. As the phase transition temperature of the working fluid in the pipe may be higher than the temperature of the surrounding formation, it is necessary to eliminate the possibility of heat loss at the top of the SLGHP by setting it to zero or providing a fully thermally insulated boundary. The results show that the heat output and heat output per unit wellbore length increase linearly with well depth, and the greater the given geothermal gradient and formation thermal conductivity, the larger the heat output and heat output per unit wellbore length

Keywords hot dry rock, supper long gravity heat pipe, upper limit, heat extraction rate, simulation