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Indexed by:会议论文

Date of Publication:2015-10-20

Included Journals:EI、CPCI-S

Volume:146

Page Number:639-646

Key Words:tube heat exchanger; backfill material; shape-stabilized PCM

Abstract:Fluent software was used to simulate the heat transfer performance of the U-tube heat exchangers with backfill materials of shape-stabilized phase change materials (PCMs) and crushed stone concrete in this paper. The shape-stabilized PCMs refer to a mixture of decanoic acid and lauric acid that the mass concentration of decanoic acid is 60% with10% silica and 6% expanded graphite. It makes the shape-stabilized PCM has the coefficient of thermal conductivity of 1.528 W/(m.K) and the latent heat of 109.2 kJ/kg. After the simulation of the time for 12 hours, the heat exchange for unit borehole depth of backfilling with shape-stabilized PCM is 1.23 times of the heat exchange for unit borehole depth of backfilling with crushed stone concrete. And the influence radius of backfill materials of shape-stabilized PCM is 0.9 times of the influence radius of backfill materials of crushed stone concrete. So under same area of buried pipes region the shape-stabilized PCM backfill can get heat exchange is 1.37 times of crushed stone concrete backfill. In addition, the heat conductivity coefficient of PCMs has great influence on heat pump coefficient. (C) 2016 The Authors. Published by Elsevier Ltd.