建筑给水排水设计规范(英文版).pdf 17页

'NATIONALSTANDARDOFTHEPEOPLE’SREPUBLICOFCHINA中华人民共和国国家标准CodeforDesignofBuildingWaterSupplyAndDrainage建筑给水排水设计规范GB50015-2003Editedby:ShanghaiConstructionandManagementCommitteeApprovedby:MinistryofConstructionofthePeople’sRepublicofChinaImplementedon:September1,20032003Beijing1 NOTICEThiscodeiswritteninChineseandEnglish.TheChinesetextshallbetakenastherulingoneintheeventofanyinconsistencybetweentheChinesetextandtheEnglishtext.2 NotificationofMinistryofConstructionofthePeople’sRepublicofChinaNo.138NotificationofnationalstandardCodeforDesignofBuildingWaterSupplyAndDrainagemadebytheMinistryofConstructionofthePeople’sRepublicofChinaNow“CodeforDesignofBuildingWaterSupplyAndDrainage”asthenationalstandard,withtheNo.ofGB50015-2003,andwillbeimplementedfromSeptember1,2003.Amongwhich,No.3.2.1,3.2.3,3.2.4,3.2.5,3.2.6,3.2.9,3.2.10,3.2.14,3.5.8,3.9.1,3.9.3,3.9.4,3.9.9,3.9.12,3.9.14,3.9.22,3.9.24,3.9.27,4.2.6,4.3.5,4.3.6,4.3.13,4.3.19,4.5.9,4.8.4,4.8.8,5.4.5,5.4.20aremandatoryclauses,andshouldbestrictlyimplemented.AtthesametimeTheformerCodeforDesignofBuildingWaterSupplyAndDrainageGBJ15-88shallbeabrogatedonthesamedate.ThiscodeispublishedandissuedbyChinaPlanPressorganizedbyStandard&CostResearchInstituteoftheMinistryofConstruction.MinistryofConstructionofthePeople’sRepublicofChinaApril.15,20033 PrefaceThepresentcodeisarevisionoftheformernationalstandardGBJ15-88managedbyShanghaiMunicipalConstructionCommission,compiledbyShanghaiXianDaiArchitecturalDesign(Group)Co.,LtdjointlywiththeChinaArchitectureDesign&ResearchGroupandtheArchitecturalDesignandResearchInstituteofGuangdongProvince,accordingtotheofficialdocumentNO.JB[1998]94oftheMinistryofConstructionofthePeople"sRepublicofChina.Intheprocessoftherevision,summedtheengineeringexperienceinbuildingwatersupplyanddrainageinrecentyears,developedtopicdeliberationtomajorissue,proposedthequestionnaireopinionmanuscriptandworkedoutbyEstablishmentGroupinthefoundationofwidesuggestionsfromtheunitsofdesigning,researchinganduniversitiesallourcountry.Themajorrevisionsoftechnologyare(1)residentialareawatersupplyanddrainagedesignhasbeenadded;(2)dwellingandpublicbuildingsratedwaterconsumptionhasbeenreadjustedandadded;(3)themeasurestopreventpollutioninpipeconnecthavebeenadded;(4)appliedtechnologyofnewtypesofpipehasbeenadded;(5)probabilityformulaofcalculatingsecondflowofdomesticwatersupplyhasbeenadopted;(6)hydrauliccalculationofvariedtypesofpipehasbeenunified;(7)recyclewatertreatmentofaquaticrecreationpoolhasbeenadded;(8)thedesignforcoolingwaterandrecyclewaterhasbeenadded;(9)detailsofhospitalsewage,watersupplyanddrainageforswimmingpoolexpressedinassociationstandardshavebeendeleted,onlyprovisionsofprinciple,safetyandsanitationreserved;(10)theprovisionsonwatersupplyanddrainageforproductiontechnologyhavebeendeleted;(11)theparameterofpressureflowofroofrainwaterhasbeenadded;(12)appliedrangefordesignheatconsumptionofmaximumhourwithcentralhotwatersupplyhasbeenreadjusted;(13)calculationofnaturalcyclehotwaterpipesystemhasbeendeleted;(14)technologyessentialandparameterofhotwatermachinesetandwaterheaterhavebeenaddedand(15)relevantcontentsoffinedrinkingwaterpipesystemhavebeenadded.Theinformationandprovisionsrevisedwillbepublishedonthemagazine“standardizationofengineeringconstruction”whilethecodeneedstoreviseinpart.Thecompulsoryprovisionsinthecodethatindicatedbyboldfacetypemustcarryoutstrictly.MinistryofConstructionofthePeople"sRepublicofChinawillberesponsibleforsupervisionofthepresentcodeandexplanationaboutthecompulsoryprovisions，ShanghaiMunicipalConstruction4 CommissionforitshandledandShanghaiXianDaiArchitecturalDesign(Group)Co.,Ltd.foritsspecificexplanation.Ifusersfind,inthecourseofexecutionofthepresentcode,anypointswhichneedtobemodifiedorsupplemented,theyarerequestedtogivetheirsuggestionsandconcerneddocumentstoShanghaiXianDaiArchitecturalDesign(Group)Co.,Ltd.（ShanghaiShiMensecondroad258thModernarchitecturaldesignedifice,nationalstandard“codefordesignofbuildingwatersupplyanddrainage”ManageGroup,ZIPcode:200041）forreferenceduringthenextrevisionofthepresentcode.Chiefeditorialunit,participatingunitsandmaindraftingstaffsofthiscode.Chiefeditorialunit:ShanghaiXianDaiArchitecturalDesign(Group)Co.,Ltd.Participatingunits：ChinaArchitectureDesign&ResearchGroupArchitecturalDesignandResearchInstituteofGuangdongProvinceMaindraftingstaffs：ZhangMiao,LiuZhenyin,HeGuanqin,FengXudong,SangLuqing5 Contents1General..................................................................................................................................12Terms、Symbols.....................................................................................................................22.1Terms..............................................................................................................................22.2Symbols...........................................................................................................................73Watersupply..........................................................................................................................123.1Ratedwaterconsumptionandwaterpressure.......................................................................123.2Waterqualityandwaterqualitypollutionprotection.............................................................193.3Systemselection..............................................................................................................203.4Pipematerial，fittingsandwatermeter...............................................................................213.6Designflowandhydrauliccalculationofpipe......................................................................273.7Watertower,Watertank,Reservoir.....................................................................................323.8Pressurizingequipment,pumphouse..................................................................................343.9Swimmingpoolandaquaticrecreationpool.........................................................................373.10Coolingtowerandcirculationcoolingwater......................................................................403.11Waterscape....................................................................................................................424WaterDrainage......................................................................................................................444.1Selectionofdrainagesystem..............................................................................................444.2Sanitaryfixtureandwaterlock...........................................................................................444.3Pipelocationandpipelining...............................................................................................454.4Calculationofdrainagepipe..............................................................................................494.5Pipematerialfittingsandinspectionwell.............................................................................534.6Ventpipe.........................................................................................................................564.7Sewagepumpandcatchpit...............................................................................................584.8Localdomesticsewagedisposal.........................................................................................594.9RainWater......................................................................................................................625Hotwateranddrinkingwatersupply.........................................................................................675.1Ratedconsumption,temperatureandqualityofhotwater......................................................675.2Selectionofhotwatersupplysystem..................................................................................705.3Calculationofheatconsumption,hotwaterquantityandheatingequipmenthotsupply.............725.4Waterheatingandstorage..................................................................................................755.5Calculationofnetwork.....................................................................................................816 5.6Pipe,fittingandpipelinelaying..........................................................................................835.7Potablewatersupply.........................................................................................................85AppendixAResidentialdistrictundergroundpipeline(structure)minimumnetclearancebetweenlines.................................................................................................................................................87AppendixBValvesandscrewfittingsresistancelossconvertedlengthofcompensation....................88AppendixCWatersupplypipesectionsanitaryfixtureswatersupplyequivalentsimultaneouslyoutflowprobabilitycalculatedequation,acoefficientvaluestable............................................................89cAppendixDWatersupplypipesectiondesignedsecondflowcalculationtable.................................90AppendixEDrinkingwaternumberoftapssimultaneouslyuseinthecalculatedpipesection...........104Explanationofwordinginthisstandard........................................................................................1057 1General1.0.1Thiscodehasbeenpreparedforthepurposeofensuringthequalityofbuildingwatersupplyanddrainagedesign,setthedesigntomeetthebasicrequirementofsafety、hygiene、applicability、economy.1.0.2Thiscodeisapplicabletotheresidentialarea、civilbuildingwatersupplyanddrainagedesign,andalsoapplicabletotheindustrialbuildingdomesticwateranddrainageandfactoryroofrain-fallrun-offdesign.Butwhendesignthefollowingprojects,currentrelevantspecifiedcodeorregulationmustbecomplied:1Collapsiblesoil、perenniallyfrozensoilandexpansivesoilregionbuilding.2Buildingwithanti-seismicintensitymorethan9.3Mineralwatercure,civilairdefenseworks.4Industrialproductionwatersupplyanddrainage.5Buildingreclaimedwater.1.0.3Buildingwatersupplyanddrainagedesignmustmeettheapplicationdemandsandalsoprovideconvenienceforconstructioninstallation、operationmanagement、maintenanceinspectionandsafetyprotection.1.0.4Buildingwatersupplyanddrainageengineeringdesignmustcomplywiththiscode,inaddition,mustcomplycurrentrelevantnationalstandardcodesrequirement.1 2Terms、Symbols2.1Terms2.1.1PotablewaterWaterqualitymeetsportablewaterhygienicstandardapplytousualdrinkingandwashingwater.2.1.2Non-potablewaterWatermotsafefordrinkingorforpersonalorculinaryuse,applytowashsanitaryfixture、vehicle、roadsprinkling、irrigategreenbelt、complementairconditioncirculatingwater.2.1.3HourlyvariationcoefficientRatiobetweenmaximumdailymaximumhourlywaterconsumptionandaveragehourlywaterconsumption.2.1.4MaximumhourlywaterconsumptionWithinmaximumdailywaterconsumptiondaytime,themaximumwaterconsumptionperhour.2.1.5BackflowpollutionAconditionwhichmayoccurinthepotablewaterdistributionsystem.1Duetonegativepressureinthepipeline,causingareversalofflowfromwaterstoragetank,plumbingfixtureliquidmixturebackflowwater.2Duetonon-drinkingwaterorotherliquidmixtureflowintowatersupplysystem.2.1.6Airgap1Theverticalspacedistancebetweenthelowestpointofwatersupplypipelineoutletandthereceptororfixturewhichwateroverflows.2Theverticalspacedistancebetweenthelowestpointofindirectdrainagefacilityorstorageoutletandthereceptororfixturewhichwateroverflows.2.1.7Flood-levelrimTheedgeofthereceptororfixturewhichwateroverflows.2.1.8ServicepipeThispipefromthewatermaininthestreetormunicipalpipelineofsupplytothebuildingservedarea.2.1.9BuildingunitepipeWatersupplyanddrainagepipelinelayingaroundthebuildingdirectlyconnectwithbuildinginletandoutletpipe.2.1.10InletpipePipebetweenwatermeterinbuildingandoutdoorbuildingunitepipe.2.1.11VerticaldivisionblockThebuildingwatersupplysystemisverticallydividedintoacertainnumberofblocks.2.1.12ParallelwatersupplyWatersupplysysteminverticaldivisionblockwithparalleldistributionpattern.2.1.13SerieswatersupplyWatersupplysysteminverticaldivisionblockwithseriesdistributionpattern.2 2.1.14ExposedinstallationIndoorpipelinewithexposedinstallation.2.1.15Concealedinstallation,embeddedinstallationIndoorpipelineinstalledinwallchannel/wellorpipeduct,orconcededinbyarchitecturaldecoration.2.1.16ManifoldAfittingorpipewithmanyoutletsorconnectionsrelativelyclosetogether.2.1.17compressionconnectionsPipeconnectionbycompressedthespigottothebelloracoupling.2.1.18CouplingconnectionsPipeconnectionbyusingspecialpipeclampandclampring-connectingpattern.2.1.19CoefficientofexpansionTheincreaseinunitpipelinelengthforonedegreeriseintemperature.2.1.20PlumbingfixtureInstalledreceptacles,deviceorappliancewhicharesuppliedwithwaterorwhichreceiveliquidorliquid-bornewastesanddischargesuchwastesintothedrainagesystemtowhichtheymaybedirectlyorindirectlyconnected.2.1.21FixtureunitAquantityintermsofwhichtheloadproducingeffectsontheplumbingsystemofdifferentkindsofplumbingfixtureareexpressedonsomearbitraitychosenscale.2.1.22RateofflowThequantityofwaterlowsoutinaunitetimeofaplumbingfixture.2.1.23DesignflowTheaveragequantityofflowofwatersupplyorwaterdrainageinacertainperiod,itisthebasicdesignflowofbasicofbuildingwatersupplyanddrainagepipelinesystem.2.1.24HeadlossThelossofpressure(orwaterhead)inwatersupplyanddrainagepipesystem.2.1.25PneumaticwatersupplyWatersupplypattern,acompositesetofpumpandpressurevesselandaccessories,waterpumpsintopressurevessel,thecompressairofvesselautomaticallyregulatetheamountofeatersupplyandkeepthepressureofwatersupply.2.1.26PointofdistributionPointsofwaterconsumptionofwatersupplysystem.2.1.27CirculatingperiodRatiobetweencirculationcapacityperunitoftimeperiodandtheeffectivewatervolumeincirculatingsystemstructureandthetransmissionpipeline.2.1.28BackwashWhenfiltercloggingoccurs,flashbackwithcomparativehigh-pressurewaterflow.2.1.29Unassuredhourforaverageyear3 Yearlyaveragevalueofaccumulatedaverageyearunassuredtotalnumberofhours.2.1.30WaterqualitystabilizationtreatmentWatertreatmentprocess,keeptheconcentrationofcalciumcarbonateandcarbondioxideinanequilibriumstateinthecirculatingcoolingwater(neithercalciumcarbonatedepositnorsolutioncorrosion),andrestrainbacteriaproduction.2.1.31CycleofconcentrationRatioofsaltconcentrationbetweencirculatingcoolingwaterandtheaddedwater.2.1.32Self-primingstThetopofcentrifugalpumpwithhorizontalaxis,1stageinletofcentrifugalpumpwithverticalaxiswithmultistagearesetbelowthelowestdesignstartingelevation,startupbygravityflowofwaterintothepumpbody.2.1.33Waterscape,fountainArtificialbuildupwaterscape,foundation.2.1.34DomesticsoilBuildingsewagecontaininghumanwaste.3.1.35DomesticwastewaterBuildingdrainfromdomesticwashwater.3.1.36DomesticsewageThewater-bornewastesderivedfromordinarylivingprocesses.3.1.37Buildingdrain,outletpipeThatpartofthelowestpipingofadischargesystemwhichreceivesthedischargefromsoil,wasteandotherdrainagepipesinsidethewallsofthebuildingandconveysittotheoutdoormanhole.3.1.38Verticalpipe,riser,stackAnypipeorfittingwhichmakesanangleof45°ormorewiththehorizontal.3.1.39HorizontalpipeAnypipeorfittingwhichmakesanangleoflessthan45°withthehorizontal.2.1.40CleanoutFittingforinsidepipecleaninginstalledonhorizontaldrainpipe.2.1.41Checkhole,checkpipeWithopencover,setonpipelinesystemforinspectionandcleaning.2.1.42TrapAfittingordevicewhichprovidesaliquidsealtopreventtheemissionofsewergasseswithoutmateriallyaffectiontheflowofsewageorwastewaterthroughit.2.1.43Waterseal(tropseal)Themaximumverticaldepthofliquidthatatrapwillretain,measuredbetweenthecrownweirandthetopofthedipofthetrap.2.1.44HpipeHtypefittingforconnectionverticaldrainpipeandventpipe.2.1.45Ventpipe4 Partoftheventsystemfordrainagesystemaircirculation,stablepressure,preventthefailureofwaterseal.2.1.46VentstackVerticalventpipeinstalledtoprovidecirculationofairtoandfromthedrainagesystemandwhichextendsthroughoneormorestories.2.1.47SpecificventstackVerticalventstackonlyconnectwithverticaldrainpipe,fortheaircirculationofverticaldrainpipe.2.1.48VentheadersVentpipesectionconnectwithseveralventstacksorverticaldraintopventsectionandstretchoutdoorintoopenair.2.1.49MainventTheprincipalarteryoftheventingsystemtowhichventbranchesmaybeconnected.2.1.50ContinuousventstackVentstackonlyconnectwithloopvent,foraircirculationofdrainhorizontalbranch.2.1.51LoopventAcircuitventpipesectionwhichloopsbacktoconnectwithastackventinsteadofaventstack.2.1.52FixtureventPipesectionfromtheoutletofthetrapofplumbingfixturetotheventstack..2.1.53Yokevent,yokeventpipePipesectionconnectingthedrainverticalpipetotheventstack.2.1.54AirgapdrainagesystemTheoutletofwastepipeoffixtureandthefloodrimofthereceptorwhichisdischarging.2.1.55BurieddepthVerticaldistancebetweenburiedpipetoptothegroundsurface.2.1.56AngleofturningflowAnglebetweenoriginalflowdirectionandturningflowdirection.2.1.57DepthratioDegreeoffullnessofwaterflowintheconduit,ratiobetweenwaterdepthinpipeandpipediameter.2.1.58GreaseinterceptorSmalltreatmentstructureforintercept,collectgreasefromdomesticwastewater.2.1.59CoolingtankTreatmentstructuretodecreasetemperatureofdrainwater.2.1.60SeptictankAreceptaclewhichreceivesthedischargeofadrainagesystemforratainsolid,digestorganicmatterthroughaperiodofdetentionandallowtheliquidtodischargeintotheoutsidesoilpipe.2.1.61ReclaimedwaterEffluentfromawastewatertreatmentplantthathasundergoneexternaltreatmenttoremoveharmfulpathogens,organicmaterialandheavymetals.2.1.62Hospitalsewage5 Polluteddrainagewaterfromhospital.2.1.63PrimarytreatmentMechanicaltreatment,wastewaterprimarytreatedbymechanicalmeasures.2.1.64SecondarytreatmentCompositeofmechanicaltreatmentandbiochemicalorchemicaltreatmentforwastewatertreatmentprocess.2.1.65AirchangeRatiobetweenvolumeofroomspaceandvolumeofdrawinorblow-offtheventilationsystemwithinaunitoftime.2.1.66RainfallintensityRainfallinaunitoftime,usuallyexpressedasmm/min(orL/s·h).2.1.67RecurrenceintervalThroughstaticanalysisoflongtimeobservedrainfallrecord,equalorgreaterthansomestormintensityrainfalloccuronceaverageintervaltime,theexpressedunitisusuallyinyear.2.1.68DurationofrainfallAnycontinuoustimesectionofrainfallduration,theexpressedunitisusuallyinmin.2.1.69InlettimeTimeofrainwaterfromcorrespondcatchmentareafarthestspotsurfaceflowintodrainpipeinlet,theexpressedunitisusuallyinmin.,abbreviatedinlettime.2.1.70TimeofflowTimeofrainwaterflowinthepipe,theexpressedunitisusuallyinmin,abbreviatedtimeofflow.2.1.71Catchmentarea22Drainconduitforrainfallcatchmentarea,expressedunitusuallyinmofkm.2.1.72GravityflowstormdrainagesystemHydraulicdesignofstormdrainagepipelineisbasedongravityflowsystem.2.1.73PressurestormsystemHydraulicdesignofstormdrainagepipelineisbasedonpressureflowsystem.2.1.74GullytrapGroundsurfacerainwaterinletwellwithgullygratingsandframes.2.1.75Downpipe,downspoutDownpipeinstalledoninsideoroutsidebuildingwallappliedtodrainroofrainwater.2.1.76HangedpipeHorizontalpipehangonbuildingfloor,beamorrooftruss.2.1.77RainstrainerAreceptorfacilityreceivesroofsurfacerainwaterflowintodownpipe.2.1.78RunoffcoefficientRatiobetweenvolumeofcertaincatchmentrainwaterandvolumeofrainfallwater.2.1.79Centralizedgotwaterheat-supplysystemHotwatersupplysystemforonesetormanysetbuilding.6 2.1.80Regionalhot-watersupplysystemAsmallhotwatersupplysystemusedonlytosupplysingleorseveralpointofdistribution.2.1.81Open-typehot-watersupplysystemHotwaterpipesystemisopentotheairinthehotwatersupplysystem.2.1.82Closed-typehot-watersupplyHotwaterpipesystemisclosedtotheairinthehotwatersupplysystem.2.1.83OnepipelinehotwatersystemHotwatersystemwithonepipesupply,onetemperature,nowatertemperatureregulationoftheraterusespot.2.1.84HeatsourceEnergyforheatinghotwater.2.1.85HeatingmediumHeattransmissioncarrierforheat-supplysystem.Usuallyishotwater,steam,smoke.2.1.86WasteheatDischargefromindustrialproductionwithheatedwastesuchaswastesteam,hightemperaturewastewater,hightemperaturesmoke.2.1.87DesignmaximumheatconsumptionofonehourMaximumheatconsumptionperhourinthehotwatersupplysysteminstallation.2.1.88ReversedreturnhotwatersystemThelengthofsupplyandreturnpipelineisnearlyequalinahotwatersupplysystem.2.1.89HeatmediumcirculationsystemTheheatmediumcirculatingsystembetweensteamboilerandwaterheaterorhotwaterboilerandhotwaterstoragetankinthecentralhotwatersupplysystem.2.1.90UpperpipewatersupplysystemWatersupplyhorizontalpipeisinstalledattheupperpartofdistributionpipesystem,waterflowsdownwardthroughverticalpipe.2.1.91LowerpipewatersupplysystemWatersupplyhorizontalpipeisinstalledatthelowerpartofdistributionpipesystem,waterflowsupwardthroughverticalpipe.2.1.92WaterreturnpipePartofahotwatercirculationsysteminwhichtherestorationtothepointofheatingsourceisaccomplished.2.1.93FinedrinkingwaterRawwaterconfirmstodrinkstandardqualitythroughthoroughpurificationcandrinkdirectly.2.2Symbols2.2.1Flowrate,flowvelocityq－Watersupplyflowg7 q－Flowrateofwatersupplyordrainofplumbingfixtureoq－Drainflowpq－Ratedhotwatersupplyrq－Designedhourlyhotwatersupplyrhq－Hourlyratedhotwatersupplyofplumbingfixturehq－Circulationflowxq－Maximumflowmaxq－Replenishingwaterbcq－Designedrainwaterflowyq－Designedrainfallintensityjq－Lossofwaterduetowindageincoolingtowerfq－Lossofwaterdueleakageincoolingtowersq－Lossofwaterdueevaporationincoolingtowerzq－Pumpoutflowbv－Averagewaterflowvelocityinthepipe2.2.2Waterpressure,lossofwaterheadR－HydraulicradiusI－HydraulicgradientP－Pressurei－Lossofheadofunitlengthpipelineh－Lossofheadofcirculationflowpassthroughdistributionpipenetworkph－Lossofheadofcirculationflowpassthroughreturnpipe/networkxH－NaturalpressureofthefirstcirculationpipexrH－Pumpheadb8 2.2.3GeometricalcharacteristicsF－HeatingareajrF－Catchmentareawh、H－HeightV－TotalvolumeofairpressurewatertankqV－Ratervolumeofairpressurewatertankq1V－Regulatedvolumeofairpressurewatertankq2V－VolumeofheatstoragerV－EffectivevolumeofexpansionwatertankpV－VolumeofexpansionwatertankeV－Watervolumeofhotwaterpipelinesystemsd－Calculatedpipeinteriordiameterj2.2.4Calculationcoefficientk、a－Coefficientdeterminationbasedontheuseofbuildingb－PercentageofplumbingfixtureforwatersupplyanddrainagesimultaneouslyandpercentageofplumbingfixtureworksimultaneouslyN－Concentrationmultiplenn－CoefficientofpiperoughnessK－CoefficientofheatconductionK－HourlyvariablecoefficienthU－ProbabilityofsimultaneousoutflowofwatersupplyofplumbingfixtureU－Probabilityofaverageoutflowofwatersupplyofplumbingfixtureduringmaximumwaterousagea－Factorofsafetyaa－Workingpressureratioofairpressurewatertankb9 a－CoefficientcorrespondtoUcob－VolumecoefficientofairpressurewatertankY－RunoffcoefficientM－Discountedcoefficienth－Effectiveheatstoragevolumecoefficiente－CoefficientofheattransmissioneffectivenessduetoscaledepositandunevendistributionofheatmediaC－HeatlosscoefficientofhotwatersupplysystemrC－HayenWilliamsroughnesscoefficienth2.2.5Heat,temperature,specificgravityandtimeQ－DesignedhourheatsupplygQ－DesignedhourheatconsumptionhQ－HeatdemandforheatinghotwaterzQ－Hotlossofdistributionpipelinest－Rainfalldurationt－Timeofgroundsurfacewatercatchment1t－Timeofstormwaterflowinpipe2T－Timeofdurationt－Temperatureofhotraterrt－Temperatureofcoldwaterlt－Initialtemperatureofheatedwaterct－FinaltemperatureofheatedwaterzDt－Calculatedtemperaturedifferencejt－Initialtemperatureofheatmediamct－Finaltemperatureofheatmediamz10'