Empirical Validation of Parameter Studies on Heat Transfer through Glazing System Using Window 6.3 Software

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1 Sunny Kumar t al Int. Journal of Enginring Rsarch an Applications ISSN : 48-96, Vol., Issu 6, Nov-Dc 0, pp RESEARCH ARTICLE OPEN ACCESS Empirical Valiation of Paramtr Stuis on Hat Transfr through Glazing Systm Using Winow 6. Softwar Sunny Kumar*, Anuranjan Shara**an Vijay Kumar*** *Rsarch Scholar, (Dpartmnt of Mchanical Enginring, Rayat Bahra Institut of Enginring An Bio- Tchnology, Mohali (PB), Inia ** Associat Prof., (Dpartmnt of Mchanical Enginring, Rayat Bahra Institut of Enginring An Bio- Tchnology, Mohali (PB), Inia *** Rsarch Scholar, (Dpartmnt of Mchanical Enginring, Rayat Bahra Institut of Enginring An Bio- Tchnology, Mohali (PB), Inia) ABSTRACT Hat transfr through iffrnt mos from outsi nvironmnt to insi occur by conuction, convction an thrmal raiation. Inclusion of automatic-avanc-gnration-softwar; WINDOW 6. maks possibl th tail tru pictur of th impact of glaz matrial & its thicknss/ pan spacing on its Thrmal Transmittanc. This softwar maks th usr unrstan th thrmal prformanc of glazing systm without xtnsiv knowlg of numrical mthos of hat transfr. Th U-valu an solar hat gain cofficint ar th ky paramtrs to analyz hat transfr through winow. Howvr in th absnc of solar raiations U-valus is th only triggr. Thrfor, an attmpt has bn ma to carry out th stuy to calculat th U-valu for iffrnt glazing systms with varying thicknss/pan spacing in prvailing sasons. Composit climat of Chanigarh prsisting in iffrnt sason is consir for th stuy. Th U-valu obtain from simulation is valiat using th guar hot plat apparatus. Aftr through analysis an vn consiring th conomical ffcts, th authors rcommn l Glaz winow with mm pan spacing to b prfctly us in Chanigarh rgion. I. Introuction Hat transfr through a singl/oubl Glaz Winow tak plac through thr mos of hat transfr i.. conuction, convction an raiation. Conuction occurs in winow pans an convction in flui an raiation through lctromagntic wavs. Hnc convction/raiation occurs in cavity an at th inoor an outoor facs of winow []. Winow with both goo looks an sir control for hat flow rquirs a thorough unrstaning of mchanism of how rspons to solar gain an thraftr masurs ns to b takn to control that hat transfr. Normal clar is almost transparnt to high frquncy solar raiation, but is a ifficult to low frquncy or long wav raiation []. Th solar hat nrgy passing through th glazing warms up th various surrouning surfac by absorption an ths surrouning surfac thn bcom hat raiators of low frquncy r-mitt hat which is trapp insi causing th tmpratur to ris. Hnc ASHRAE vis mtho for trmining hat transfr through winow an prsntly in orr to calculat th U-valu & solar hat gain cofficint through winows []. In th vlop countris, winows with glazing systm or oubl glaz winows ar us whr as in Inia singl glaz winows ar us. Ths ar bing us sinc a long ago without propr invstigation of thir U-Valu, SHGC (Solar Hat Gain Cofficint). Till now not much invstigation has on in this fil. Hnc in th prsnt invstigation a singl glaz an oubl glaz winow with iffrnt pan-pan spacing is bing consir. II. Softwar An Simulation. Softwar Th Winow 6. softwar is us, for simulating th hat transfr through glaz winows. This softwar is publicly availabl LBNL WINDOW IBM PC compatibl computr program, which is vlop by th builing tchnologis group at th Lawrnc Brkly Laboratory. It is hlpful in calculating th thrmal an optical proprtis compulsory for hat transfr analyss of fnstration proucts. WINDOW 6. is th latst in a sris of programs rlas by th Lawrnc Brkly Laboratory, in which th nw proucts with masur thrmal an optical proprtis can also b a to th softwar atabas. Main paramtric changs can b ma in this softwar whil molling gomtrical mols of iffrnt glazing systms. Th paramtrs which can b altr inclu spacing btwn iffrnt layrs, typ of glazing, nvironmntal conitions, flui in btwn th pans an so many mor. Thus using iffrnt input paramtrs, rsults of various output paramtrs such as SHGC, U-valu, K ff, (Effctiv thrmal conuctivity) tc. can b trmin. All th calculations procurs for 86 P a g

2 Sunny Kumar t al Int. Journal of Enginring Rsarch an Applications ISSN : 48-96, Vol., Issu 6, Nov-Dc 0, pp trmining various rsponss ar availabl at LBNL wbsit [4]. Simulation Th simulat stuy is intn on th basis of on factor approach to tak account of th ffct of control factors on rspons factor. Th pans of siz 65 x 65 x ar slct for conucting simulation-runs for various glazing systms. A rang of lvls of iffrnt input simulation factors is consir as in tabl. Tabl- : Control Paramtrs Lvls Control Paramtrs Glazing Pan-Pan Typ Spacing Th singl rspons paramtr U-valu is masur. Th full factorial approach consists of a sign of total 8 xprimnts, as shown in tabl. Tabl : Dsign of Exprimnts Lvl Glazing Spacing Climat A B C A B C A B C 4 A B C 5 A B C 6 A B C 7 A B C 8 A B C 9 A B C A4 B4 C A4 B4 C A4 B4 C A5 B5 C 4 A5 B5 C 5 A5 B5 C A6 B6 C 7 A6 B6 C 8 A6 B6 C For simulation hat transfr through th chosn configuration along with th input paramtrs having valus consqunt to composit-climatic zon of Inia is us. Avrag win-sp an solar raiation ar obtain from th intrnt [5] to f inputs to th softwar. Th innr room tmpratur[6] is kpt at th sign conitions accoring to Inian climat [7]. For convctional hat transfr, ASHRAE/NFRC mol an Winwar Dirctional mol ar slct through th softwar. Both th Climatic Conitions (mm) l 4 5 ffctiv sky missivity an th ffctiv room missivity ar assum to b qual to. Th glazing systms ar us to ruc th ffct of U-Valu. Th glazing units can b catgoriz into singl or multipl glazing layrs (oftn known as Insulating Glazing Units IGUs) ar oubl glazing, tripl glazing, an quarupl glazing. For th prsnt invstigation, a singl glaz an oubl glaz winow with clar mm thick is slct for th analysis of U-valu [8].Th slct glazing systm is as blow tabl. Tabl : Dscription of slct glazing library S. No Typ of Glazing Systm Layrs.. l. l 4. l 5. l 6. l Layr Layr mm mm mm mm mm 87 P a g Layr Th various solar an optical proprtis of clar ar givn in tabl 4. Tabl-4: Solar an optical proprtis of Dscription Glass Solar Visibl IR Trans, Front (T sol ) Trans, Back (T sol ) Rflction Front (R sol ) Rflction Back (R sol ) Trans, Front (T vis ) Trans, Back (T vis ) Rflction Front (R vis ) Rflction Back (R vis ) Emis, Front (Emis) Emis, Back (Emis)

3 Sunny Kumar t al Int. Journal of Enginring Rsarch an Applications ISSN : 48-96, Vol., Issu 6, Nov-Dc 0, pp Th softwar givs from to slct th flui btwn th pan.it has th ight typs of flui: i) Air ii) Argon iii) Krypton iv) Xon v) Air 5% an Argon 95% vi) Air %, Argon % an Krypton 66% mix vii) Air 5% an Krypton 95% mix viii) Air % an Argon 90% mix. For th prsnt invstigation air is consir.th proprtis of air at stanar tmpratur an prssur is givn in th blow tabl l l l l l Col - Col Tabl- 5: Proprtis of air Nam Typ Air Pur Conuctivity W/m-k Viscosity Ns/m Cp J/kg-K 06.7 Dnsity Kg/m.97 Prantl 0.77 Tabl-6: Full factorial sign for valuating U-valu Glazi Spaci Exprim Simulat S. Clima ng ng ntal U- U- No t Typ (mm) valu Valu l Hot.98.5 l.68.0 l Hot l Hot l l l l l l Hot Hot Hot III. EXPERIMENTAL SET UP Th apparatus consists of primarily two coppr plat s (i.. hot coppr plat, col coppr plat) watr bath, coppr tubs, tmpratur inicators of th bath, rota-mtr, hatrs i.. main an guar hatrs, glazing systm, powr supply systm an othr accssoris. This apparatus is similar to th apparatus us by Wright an Sullivan [9]. Th siz of two coppr plats (hot plat an col plat) is 65x65x.5 mm ach. Th plats ar plac in such a arrangmnt so that thy kp facing ach othr an can b maintain at constant tmpraturs. Both plats ar hl at rquir constant tmpratur by a circulating a stay flow mixtur of watr an glycol through a manifol of tubs attach at th back of th coppr plats. Th warm coppr plat contains thr guar hatr plats, in th vrtical position at qual istanc. Th hat transfr that taks plac ovr th fac of ach of th guar hatr can b masur. Th ajustmnt of th lctrical powr suppli to th hatr plat is ma until zro tmpratur iffrnc is achiv btwn th hatr plat an th warm coppr plat. At this position, thr will b no hat transfr btwn th hatr an th warm coppr plat an all th lctrical nrgy suppli is transfrr across th gap th col coppr plat. Th constant tmpratur baths which f th two coppr plats can b start. Fig-: Schmatic of xprimnt st up 88 P a g

4 Sunny Kumar t al Int. Journal of Enginring Rsarch an Applications ISSN : 48-96, Vol., Issu 6, Nov-Dc 0, pp Mthoology: Th outr pan an innr pan tmpratur iffrnc from simulat stuy is consir for tmpratur iffrnc of hot an col plat in th guar hot plat apparatus. Th sampl is sanwich btwn th hot an col plats to trmin its U-Valu. Th masuring mthoology [9] us is iscuss blow: For masuring th hat flux from th xpos surfac of a GHP, th rat of lctrical nrgy suppli to th hatr plat Q, is trmin by masuring th hatr wir voltag V an currnt I, irctly by using a igital volt mtr an an ammtr. Q = I V (i) Th hat flux from th fac of hatr plat, P is thn calculat by using hat flux mtr output voltag, v as: P = (Q a. v)/ahp (ii) Whr a = hat flux mtr calibration constant A hp = Fac ara of th hatr plat Aftr th hat flux, has bn masur; th to C-valu of th glazing systm, can b masur as: C = (( T/P) Rn) (iii) Whr T = tmpratur iffrnc btwn th warm an col coppr plat An Rn = thrmal rsistanc of noprn sht = 0.07m C/W Th U- valu bas on th abov masurmnts can finally b fin out as: U = (C + h + h ) Whr h= inoor hat transfr cofficint h= Outoor hat transfr cofficint In this invstigation th xtrm climat & tmpratur conition of Chanigarh, Inia has bn consir as shown in tabl 7. Tabl -7: Composit climatic conition Composit Climat Conition Climat Conition Tout ( o C) Tin ( o C) Solar raiation W/m Win sp m/s Cool Th ffct influnc of iffrnt paramtrs viz. typ glazing systm (singl glazing, oubl glazing), pan-pan spacing an climatic conitions (,, ) is invstigat. Obsrvations accoring to full factorial sign ar ma by kping on paramtr fix an varying th rst paramtrs on by on. Both th simulat an xprimntal rspons valus for th plann sign ar shown in th tabl 8. IV. 4. Rsults 4. Comparison of xprimntal an simulat U- Valus Tabl-8: Simulat an Exprimntal U-Valus S.N Glazi ng Typ l l l l l l l l l l l l l l l Spaci ng (mm) Climat Hot - Hot - Hot - Exprim ntal U- valu A prusal of ata rprsnt in th Tabl 8 shows th significant variation in th simulat softwar U- valu u to all th thr factors i.. sason, typ of glazing systm an pan-pan spacing (for l glaz winows). Highst U valu is obsrv in singl glaz winow having 6.46 W/m K in sason whil th lowst U valu is P a g Simula t U- Valu

5 Sunny Kumar t al Int. Journal of Enginring Rsarch an Applications ISSN : 48-96, Vol., Issu 6, Nov-Dc 0, pp W/m K in th oubl glaz winow having mm pan-pan spacing DG,H-D SG,H-H DG,H-H SG,C-D DG,C-D SG- Glaz DG- l Glaz H-D - H-H C-D - 0 mm mm5 mm mm mm Fig: Graphical rprsntation of Exprimntal an Simulat U-Valu 4. Th ffct of spacing It has bn invstigat th ffct of changing pan spacing from mm to mm, mm, mm an thn to mm th U-valu crass for all climatic conitions (,, ) at iffrnt lvls, whos rsults ar list as unr: Cas: Th U-Valu crass by a minimum of % whil incrasing th pan-pan spacing from mm to mm, mm, mm an thn to mm in Conitions for oubl glazing systm. Cas: Th U-Valu crass by a minimum of % whil incrasing th pan-pan spacing from mm to mm, mm, mm an thn to mm in Conitions for oubl glazing systm. Cas: Th U-Valu crass by a minimum of 6% whil incrasing th pan-pan spacing from mm to mm, mm, mm an thn to mm in Col - Conitions for oubl glazing systm. Th rsult ar similar Collins(99) [] Fig: Graphical rprsntation of th ffct of Pan- Pan Spacing 4. Th ffct of climat It has bn obsrv that by changing pan spacing from mm to mm, mm, mm an thn to mm th U-valu crass for all climatic conitions (,, ) at iffrnt lvls, whos rsults ar list as unr: Cas: Th U-Valu crass by a minimum of 0.00% whil incrasing th pan-pan spacing from mm to mm, mm, mm an thn to mm in Conitions for oubl glazing systm. Cas: Th U-Valu crass by a minimum of 0.00% whil incrasing th pan-pan spacing from mm to mm, mm, mm an thn to mm in Conitions for oubl glazing systm. Cas: Th U-Valu crass by a minimum of % whil incrasing th pan-pan spacing from mm to mm, mm, mm an thn to mm in Col - Conitions for oubl glazing systm P a g

6 Sunny Kumar t al Int. Journal of Enginring Rsarch an Applications ISSN : 48-96, Vol., Issu 6, Nov-Dc 0, pp SG DG, DG, DG, DG, DG, Fig: 4 Graphical rprsntations of ffct of climat It has bn obsrv that th minimum U- valu crass by lss than % in all th unr takn climatic conitions, Thus climatic conitions os not hav much influnc on th U-Valu. Hnc it may b nglct. 4.4 Th ffct of iffrnt glazing systms (singl glaz an oubl glaz) It has bn obsrv that by shifting from singl to oubl glaz winow, th U-Valu crass for all climatic conitions (,, ). Cas : Th U-Valu crass from 5.6 W/m K to.68 W/m K, whn oubl glaz winow having pan-pan spacing mm is us inplac of singl glaz, in Climat. Cas : Th U-Valu crass from 5. W/m K to.5 W/m K, whn oubl glaz winow having pan-pan spacing mm is us inplac of singl glaz, in Climat. Cas : Th U-Valu crass from 5.06 W/m K to.44 W/m K, whn oubl glaz winow is us inplac of singl glaz, in Climat. Fig: 5 Graphical rprsntation of th ffct of glazing systm on U-Valu V. Conclusion As lowr U-valu of th glazing systm ar sir, th following conclusions ar ma from th prsnt work: glaz winows shoul b avoi as ths hav highr U-Valu. Pan-Pan spacing has significant impact on th U-valu. During sason oubl glaz winows with a pan-pan spacing of mm is bttr as its U-Valu is.5 W/m K. During sason oubl glaz winows with a pan-pan spacing of mm is bttr as its U-Valu is.44 W/m K. During sason oubl glaz winow with a pan-pan spacing of is rcommn by th author as its U-Val is.68 W/m K. As most of th months in Inia, thr is / climat, hnc oubl glaz winow with mm pan-pan spacing is rcommn. Rfrnc [] Shara Anuranjan, Kumar, Suhir. Hat transfr through winows: A Rviw Intrnational Confrnc on Avancs in Mchanical Enginring, August -5, S.V. National Institut of Tchnology, Surat, Gujarat, Inia (009). [] Wright, J.L. A Corrlation to Quantify Convctiv Hat Transfr Btwn Vrtical Winow Glazings," ASHRAE Transactions, Vol., Pt. pp. (96) P a g

7 Sunny Kumar t al Int. Journal of Enginring Rsarch an Applications ISSN : 48-96, Vol., Issu 6, Nov-Dc 0, pp [] Wright, J.L. an Sullivan H.F. (95) "A -D Numrical Mol for Glazing Systm Thrmal Analysis," ASHRAE Transactions, Vol., Pt. pp [4] Winows an Daylighting Group, "WINDOW 6 an THERM 6 Tchnical Documntation," Lawrnc Brkly National Laboratory, Sptmbr 0. [Onlin]. Availabl: chnicaldocs.html. [Accss 8 Novmbr 0]. [5] [6] Lak, K.L, A Whit papr on manufacturing an assmbling on an afforabl quick to buil an sustainabl mass housing solution for Inian citis. Inia Concpt Hous. [7] Singh, I, Bansal, N.K., Thrmal an optical paramtrs for iffrnt Winow Systm In Inia, Intrnational Journal of Ambint Enrgy, Vol., Pt. 4, (00) pp. 0-. [8] Zhou Xu, A Numrical an Exprimntal Stuy Of Thrmal Transmittanc Of Winow Systms, National Univrsity Of Singapor.0 [9] Wright, J.L. an Sullivan H.F. "Glazing Systm U-Valu Masurmnt Using A Guar Hatr Plat Apparatus," ASHRAE Transactions, Vol.94, Pt. (88) pp. - 7 [] Collins M.R an Harison, S.J, Calorimtric masurmnt of th inwar flowing fraction of absorb solar raiation in vntian blins, ASHRARE transactions, vol 5(), 99,pp P a g