Abstract
Themiddle-deepgeothermalsourceheatpumpsystemisanewheating
technology.Comparedwiththetraditionalshallowburiedtubegroundsourceheat
pumpsystem,theundergroundheatexchangecannotonlysavethefloorspace,but
alsoreducetheenergyconsumptionofthesystem,whichisbeneficialtocleanheating.
Downholeheatexchangedeviceasthecoreofundergroundheatexchangesystem.To
ensurethestabilityandefficiencyofdownholeheatexchange,coaxialcasingheat
exchangerareusuallyselected.Thispaperadoptsanumericalheattransfermodelofa
downholecoaxialcasingheatexchangerformiddle-deepgeothermal.Thenumerical
modelconsidersthegeothermalgradientoftheundergroundrock-soil,thebackfill
materialandtheheatcapacityofthepipewallandfluid.Calculatetheheattransfer
equationofgeothermaldownholecoaxialcasingheatexchangerunderthecondition
offixedinlettemperatureandactualengineeringdata,thisconditionismorerealistic
andmorereliable.Theheattransfercharacteristicsofdownholecoaxialcasingheat
exchangerismainlystudied.Thespecificresearchcontentisasfollows:
First,basedonmiddle-deepgeothermalwellintheproject.Extensivecollection
andarrangementofexplorationgeologicalcharacteristicsandunderground
geotechnicaldistributiondata,obtainthephysicalparametervaluestowhichthe
numericalsimulationanalysisisapplied.Explaintheengineeringprojectand
geologicaloverview,theoverallstructureoftheheatexchangesystem,thedesignof
theheatexchangetestplanandtheresultsoftheheatexchangetest.Throughthe
collationofdataandcorrespondingmathematicalcalculations,