In order to solve the frost-heaving safety problems of buried heat exchanger hydronic in ground-source heat pump

a mathematics mode1 and its contro1 equation were put forward according to heat transfer

filtration theory and mechanics of frozen soil

which is the couplings problem of temperature field

hydronic field and stress field. The temperature field

frost heaving displacement and stress distribution of ground-source heat pump in Daqing oilfield were simulated with finite elements method. The contrast and analyses are carried out according to the different soil depth

the different soil thermal conductivity in backfilled areas

the different spacing of tube foot. The results showed that the least temperature and heat affected zone in soil increases gradually with operating time. At the beginning of operation

the displacement of buried heat exchanger is small because the soil is not frozen. When the soil temperature reaches the phase temperature

soil volume increases in size

and then buried tube deforms. When soil temperature exceeds between -0.75℃ and -0.30℃

buried tube doesnt deform.