Determination of pipe wall temperature in a slinky-coil ground heat exchanger

Abstract

Spiral heat exchanger's geometry is quite complicated which required the introduction of a number of assumptions when developing analytical relationships for modelling and designing these devices. Analytical models, related to the ring system not connected to each other, are simplified. In this work, simulation calculations of the exchanger pipe wall temperatures were carried out with many rings connected together by insulated pipe sections. The calculation results were compared with the results obtained from the simplified model. It was shown that the results obtained according to the exact and simplified model do not differ significantly from each other. A comparison of the analytical results with the experimental and numerical results was also carried out. Both own and other authors' results were used. The comparative tests confirmed the correctness of the analytical model in various configurations: for a single ring, for multi-ring and multi-row systems, and for different spatial orientation of rings.