International Research Journal of Engineering and Technology (IRJET)e-ISSN: 2395 -0056 Volume: 02 Issue: 04 | July-2015 www.irjet.netp-ISSN: 2395-0072 2015, IRJET.NET- All Rights Reserved Page 1391 Experimental Thermal Analysis of Composite Roof and Its Effects on Overall Thermal Resistant in Building Envelope Mr. Sawankumar E. Patil1, Mr. Abhishek R. Deshmukh2, Mr. N.N.Shinde3, Mr. R A Charate4 1Research Student, Department of Technology, Shivaji University, Kolhapur, Maharashtra, India 2Research Student, Department of Technology, Shivaji University, Kolhapur, Maharashtra, India 3Professor, Department of Technology, Shivaji University, Kolhapur, Maharashtra, India 4Principal, Lattthe polytechnic, Sangali, Maharashtra, India---------------------------------------------------------------------***---------------------------------------------------------------------AbstractAdesignandanalysisofthreetypesof compositeroofhasbeenevaluated.Theadoptive temperatureintherangeof22Cto32Cinmoderate zone is achieved.It is important, that a designer should be able to calculate the temperatures and heat transfer rateforanycombinationofmaterialsexposedtoany climaticconditions.Thenewinnovativeandmodified compositeroofhelpsmakebuildingenvelopecoolin summerandwarminwintersandsavesenergyin respective seasons. Thecompositematerials,innovatedare concrete(M20),ExpandedPolystyrene(thermocol) foaminsulationplusferroconcrete;concreteplus Polyethylenefoaminsulation plusferroconcreteand concrete,Polyurethanefoaminsulationplus ferroconcretematerial.Thiscompositematerialis sandwichedbetweenwaterproofingcompoundlayer andarefurtheranalyzedfortechno-economical feasibility. Itisreviewedandanalyzedthat,thecomposite materialconcretewithPolyurethanefoamisbetter suitedforlowcostandcomfortasdurableroofin passivedesignsofbuildingapplications.These composite materialspropertiesare good for comfort in building conditions as compared to other materials. KeyWords:Compositeroof,comfortconditions, energysavinginbuildingenvelope,roofthermal analysis, roof and comfort analysis, techno-economical feasibility, roof cooling effect, roof thermal balance. 1. INTRODUCTION Inbuildingdesignsimpletechniquessuchasorientation, aspect,prospect,shadingofwindows,colour,and vegetationamongotherscreatecomfortableconditions. Such techniques pertain to the building envelope. Building envelopesnotonlyprovidethethermaldividebetween theindoorandoutdoorenvironment,butalsoplayan important role in determining how effectively the building canutilizenaturalresourceslikeheat,lightandwind. Thus,intelligentconfigurationandmouldingofthebuilt formanditssurroundingscanconsiderablyminimizethe levelofdiscomfortinsideabuilding,andreducethe consumptionofenergyrequiredtomaintaincomfortable conditions. Thephysicalmanifestationofsomeoftheconceptson buildingconfigurationthatcanreduceheatgaininarid andhotclimateisdepictedbyvariousfactorslike,Walls, Windows, Roofs, and Adjacent Walls etc. Inbuildingenvelopemostoftheimportantpartisroof. Roofofabuildingreceivesasignificantamountofsolar radiation.Thus,itsdesignandconstructionplayan important role in modifying the heat flow, day lighting and ventilation.AsperIndianStandardcode3792(1978),the heatgainthroughroofsmaybereducedbythefollowing methods: Insulatingmaterialsmaybeappliedexternallyor internallytotheroofs.Incaseofexternal application,theinsulatingmaterialneedstobe protectedbywaterproofingtoavoidintrusionof moisture inside the living space.Forinternalapplication,theinsulatingmaterial maybefixedbyadhesiveorbyothermeanson theundersideoftheroofs.Afalseceilingof insulationmaterialmaybeprovidedbelowthe roofs with air gaps in between.Shiningandreflectingmaterial(e.g.glazedchina mosaic) may be laid on top of the roof. Movablecoversofsuitableheatinsulating material, if practicable, may be considered. Whitewashing of theroofcanbedonebeforethe onset of each summer. Typicalheatloadsinfilteringfromvarioussides of building envelope in moderate zone in India are calculatedandisrepresentedingraph1.below. Almost 17.9% of heat is due to roof. Graph.1. Pie chart on solar radiation by heat load International Research Journal of Engineering and Technology (IRJET)e-ISSN: 2395 -0056 Volume: 02 Issue: 04 | July-2015 www.irjet.netp-ISSN: 2395-0072 2015, IRJET.NET- All Rights Reserved Page 1392 1.2 Composite Roof: Compositeroofisamixtureof multiplematerialsthatare compressedandblendedtogether.Theypossessdifferent physicalorchemicalproperties,thatwhencombined, produces a material with characteristics different from the individualcomponents.Incompositeroofnewmaterial canbepreferred,formanyreasons:commonexamples includematerialswhicharestronger,lighterandless expensivewhencomparedtotraditionalmaterials.The composite roof looks like any other roof and can be casted atsitewithduecareandhightechpractices.These compositesaretestedforISO:9705foritsfireresistance but are not analyzed for thermal transmittance for passive design applications. Typical engineered composite materials include: Compositebuildingmaterialssuchascements, concrete, ferroconcrete. Reinforcedplasticssuchasfiber-reinforced polymer. Metal Composites. CeramicComposites(compositeceramicand metal matrices). Polyurethanefoamandpolystyrenefoamand polyethylene foam insulation material. 2.0 The research criteria2.1 Selection of roof composite materials 2.2 Heat balance and its thermal Analysis 2.3 Analysis 2.1. Selection of roof composite materials Figure-1: General composite roof design 2.2 Heat Balance and its thermal Analysis Heat transfer by roof conduction and convection equations Abbreviation:- Q= rate of heat conduction (w) A = surface area (m2) U = thermal transmittance (W/ m2- K) T = temperature differenceRt = total thermal resistance hi =inside heat transfer coefficients ho= outside heat transfer coefficients L j =thickness of the jth layer. K j =thermal conductivity of its material. i = building element. Nc = number of components. x1,x2,x3arethethicknessofferroconcrete,insulation, and concrete(M20), respectively. k1,k2,k3arethethermalconductivityofferroconcrete, insulation, and concrete(M20), respectively. Therateofheatconduction(Qconduction)throughany elementsuchasroof,wallorfloorundersteadystatecan be written as [1] Q, conduction = A U T Where, A = surface area (m2) U = thermal transmittance (W/ m2- K) T=temperaturedifferencebetweeninsideand outside air (K). Itmaybenotedthatthesteadystatemethoddoesnot accountfortheeffectofheatcapacityofbuilding materials. U is given by[1] U=1/Rt Where Rt is the total thermal resistance and is given by [1] hiandhoaretheinsideandoutsideheattransfer coefficients respectively. Lj is the thickness of the jth layer and kj is the thermal conductivity of its material. Uindicatesthetotalamountofheattransmitted from outdoor air to indoor air through a given wall or roof perunitareaperunittime.ThelowerthevalueofU,the higheristheinsulatingvalueoftheelement.Thus,theU-valuecanbeusedforcomparingtheinsulatingvaluesof various building elements. Equationissolvedforeveryexternalconstituent elementofthebuildingi.e.,eachwall,window,door,roof andthefloor,andtheresultsaresummedup.Theheat flowratethroughthebuildingenvelopebyconductionis thesumoftheareaandtheU-valueproductsofallthe elementsofthebuildingmultipliedbythetemperature difference. It is expressed as: where, i = building element. Nc = number of components. International Research Journal of Engineering and Technology (IRJET)e-ISSN: 2395 -0056 Volume: 02 Issue: 04 | July-2015 www.irjet.netp-ISSN: 2395-0072 2015, IRJET.NET- All Rights Reserved Page 1393 2.3 AnalysisCase 1 Figures-2:Compositeroofstructurewith polystyrenefoam as an insulation material. WhereA= Water Proofing ferroconcrete material, B= Polystyrene Foam, C= Concrete (M20), K1=ThermalConductivityofWaterProofing ferroconcrete material, K2= Thermal Conductivity of Polystyrene Foam K3= Thermal Conductivity of concrete (M20), X1= Thickness of first layer offerroconcrete material, X2= Thickness of Polystyrene FoamX3= Thickness Concrete (M20), A= A1= A2= A3= Heat Transfer area. Graph-2: All temperature in case 1 (Polystyrene foam insulation) Vs Time in minute Case2FiguresNo3:Compositeroofstructurewith polyethylene foam as an insulation material. WhereA= Water Proofing ferroconcrete material, B= Polyethylene Foam, C= Concrete (M20), K1= Thermal Conductivity of water proofing ferroconcrete material, K2= Thermal Conductivity of Polyethylene Foam, K3= Thermal Conductivity of concrete (M20), X1= Thickness of layer first ferroconcrete material, X2= Thickness of Polyethylene Foam, X3= Thickness Concrete (M20), A= A1= A2= A3= Heat Transfer area. Graph.3:Alltemperatureincase2(Polyethylenefoam insulation) Vs Time in minute Case3Figures-4:Compositeroofstructurewith polyurethane foam as an insulation material. WhereA= Water Proofing ferroconcrete material, B= Polyurethane Foam, C= Concrete (M20), K1= Thermal Conductivity of water proofing ferroconcrete material, K2= Thermal Conductivity of Polyurethane foam, K3= Thermal Conductivity of concrete (M20), X1= Thickness of layer first ferroconcrete material, X2= Thickness of Polyurethane Foam, International Research Journal of Engineering and Technology (IRJET)e-ISSN: 2395 -0056 Volume: 02 Issue: 04 | July-2015 www.irjet.netp-ISSN: 2395-0072 2015, IRJET.NET- All Rights Reserved Page 1394 X3= Thickness Concrete (M20), A= A1= A2= A3= Heat Transfer area. Graph-4:Alltemperatureincase3(Polyurethanefoam insulation) Vs Time in minute 2.3 Techno comfort analysis Graph-5:ThermalTransmittance(U)VsMaterialsinall case 3.CONCLUSIONS Thefollowingresultswereobtainedfromtheanalysisof the composite roof structures. Incaseofcompositeroofwithinsulationofpolystyrene foam,itisobservedthattheincreaseintheinsideroom temperature is less with respect to time. If outside average temperatureis53.13Ctheninsideroomtemperatureis 32.60 C. Incaseofcompositeroofwithinsulationofpolyethylene foam,itisobservedthattheincreaseintheinsideroom temperature is less with respect to time. If outside average temperatureis60.7Ctheninsideroomtemperatureis 32.28 C Incaseofcompositeroofwithinsulationofpolyurethane foam,itisobservedthattheincreaseintheinsideroom temperature is less with respect to time. If outside average temperatureis66.84Ctheninsideroomtemperatureis 32.10 C. Finallyitisconcludedthattheinsideroomtemperature valueofcompositeroofwithpolyurethanefoamusing material is effective in transfer of less heat inside the room andhenceitisrecommendedthatthepracticeofPUFin compositeroofwillresultinenergysavingandenergy conservation in building envelope. REFERENCES [1]J.K.NayakandJ.A.Prajapati;HandbookOnEnergy ConsciousBuildingsPreparedundertheinteractive R&Dprojectno.3/4(03)/99-SECbetweenIndian InstituteofTechnology,BombayAndSolarEnergy Centre, Ministry of Non-conventional Energy Sources; May 2006. [2]B.I.Hoglund,G.P.MatalasandD.G.Stephenson; SurfaceTemperaturesandHeatFluxesforFlat Roofs;Build.Sci.Vol.2.pp.29-36.PergamonPress 1967. Printed in Great Britain. November 1966. [3]AmjedA.Maghrabi;ComparativeStudyofThermal Insulation Alternatives for Buildings, Walls and Roofs inMakkah,SaudiArabia;DepartmentofIslamic Architecture,CollegeofEngineering&Islamic Architecture,: Umm Al-Qura Univ. J. Sci. Med. Eng. Vol. 17,No.2, pp.273 -287 (2005). [4]J.Rojas,G.Barrios,G.Huelsza,R.Tovar,S.Jalife-Lozano;Heattransferthroughhomogeneous multilayeredroofsinnonair-conditionedrooms: experimentsandSimulations:Centrode Investigaci_onenEnerga,Universidad NacionalAut_onomadeM_exicoPriv.Xochicalcos/n, Col.Centro,62580Temixco,Mor.,MexicobMeccano deM_exico,AntonioDue~nez170,ZonaIndustrial, 27019, Torre_on, Coah., Mexico; September 27, 2012. [5]ST.Vasiliu;SolutionforFlatRoofs BuletinulInstitutuluiPolitehnicdinIASIPublicatde UniversitateaTehnica,,GheorgheAsachidin IasITomulLIV(LVIII),Fasc.4,2008SectiaConstruct II. Arhitectur A; 2008. [6]NayakJ.K.andFrancisS,Toolsforarchitectural design and simulation of building [7]AaronGrin,JonathanSmegalandJosephLstiburek; ApplicationofSprayFoamInsulationUnder PlywoodandOSBRoofSheathing;BuildingAmerica Report 1312; September 2013. [8]ThermalInsulationHandbookThermalInsulation AssociationofSouthernAfrica;Administeredby AssociationofArchitecturalAluminium Manufacturers of South Africa;April 2001. [9]DyannaBeckerandDaisyWang;GreenRoofHeat TransferandThermalPerformanceAnalysis;Civil andEnvironmentalEngineering;CarnegieMellon University; May 12, 2011. [10] DannyS.Parker,JeffreyK.Sonne,JohnR.Sherwin; ComparativeEvaluationoftheImpactofRoofing SystemsonResidentialCoolingEnergyDemandin Florida;ResidentialBuildings:Technologies,Design, Performance Analysis, and Building Industry Trends - 1.219. [11] SamP.Muhlenkamp,StevenE.Johnson,In-place ThermalAgingofpolyurethaneFoamRoof Insulations,ResearchandDevelopmentdivision owens coming fiberglass corporation, page no. 49-51. International Research Journal of Engineering and Technology (IRJET)e-ISSN: 2395 -0056 Volume: 02 Issue: 04 | July-2015 www.irjet.netp-ISSN: 2395-0072 2015, IRJET.NET- All Rights Reserved Page 1395 [12] MohamedKrem;EffectofBuildingMorphologyon EnergyandStructuralPerformanceofHigh-Rise OfficeBuildings;UniversityofMassachusetts- Amherst, mkrem@engin.umass.edu, May 2012. [13] EnergyConservationBuildingCodeuserGuide; Bureau of Energy Efficiency, July 2009. [14] SukhatmeS.P.,Solarenergy,2ndEdition,Tata McGraw Hill, New Delhi, 1996. [15] Manual on solar passive architecture: energy systems engineeringIITDelhiandSolarEnergyCentre, MinistryofNon-conventionalEnergySources, Government of India, New Delhi). [16] 15.ASHRAEhandbook:fundamentals,American Society of Heating, Refrigerating and Air-conditioning Engineers, Inc., Atlanta, GA, USA, 2001. [17]NayakJ.K.andR.Hazra,Developmentofdesign guidelinesonsolarpassivearchitectureand recommendationsformodificationsofbuildingbye-laws,FinalReport,R&DProjectno.10/86/95-ST, MinistryofNon-conventionalEnergySources, Government of India, New Delhi,1999. [18] SP:41(S&T)-1987-handbookonfunctional requirementsofbuildings,BureauofIndian Standards, New Delhi, 1987.