.A r a ş t ı r m a may be clear air, legibility tance such as 75 ft ( 2 3 m )o, f oarns me xoi tk es i gant saot ms oemhee idgihs t above a particular floor level. Hinge nicnetr,otdhuecceodmapt a fnl oi oo nr l er evqeul i ar enmd edni tr eocnt e dm aukpewu ap r da .i r Tbhei s is myth number two. tinhapt rtehpeasrpi nrgi n tkhleerscwodoeu l dr e aqcutiirveamtee nretsg,ari tdlwesass oassumed f height. in so doing, the sprinklers would both cool the smoke (thus depriving it of buoyancy) and drive it to the floor (by the water's momentunı). Therefore, the use of cold, chenıical sınokes (either zinc chloride or partially pyrolyzed propylene glycol) woulcl adequately late the real-worlcl situation. , siınuNotations tor Equations Ao Outlet area m Meters c. Specific heat ô Heat reıease rate cfm Cubic feet per minute Oo Discharge volume D Diameter o, Volume at distance x g Gravitational constant !rom the discharge K' Discharge coefficient 1 Time K Correction factor lor heat T Absolute temperature release rates V Velocity kW Kilowatts a Actual L Spacial dimension of interest m Model Us Liters per second p Density To raise these colcl snıokes off the floor level and insert tthhaetma nintuopwt haercel xahiar ujsett rwegoiıunl de abbeovneec, eitsswaras postulatecl y. in fact, to pass these tests that utilize extraordinarily limited ınasses of s u ccho osl t sr aı nt eogk iee sa earroes oel s , ffective in two ways. • • o the exhaust systeın of access to more concentrated volumes of smoke. MODELLING üne way that this mathematically enon can be visually deınonstratedproisvabbyl ee ı pnhpel onyo i m ng scale models. Quintiere9 discussed the requirements for dynamic similitude in some detail. Turner10 ers have laid out the mathcmatical foundations a o nf d b u o o tyh ancy in fluids, especially with respect to plumes. To deınonstrate the consequences of adherence to the ty s t rpui cc tael dU oSf c aond ae cpt ruoavl ias ti or inusm, ab1u/i 7l d- si nc ga l eh omuos idnegl awda se pc aornt ınent store. A fire had occurred in these preınises. it was observed from inside by several eyewitnesses and subsequently examined in great detail by tion between a scale modeilnvaensdtigaatroeras.l-Tlifh e e fci roer rwe l aa s thus available for comparison. The model consisted of cended vertically throughansixatfrl iouomr (l es evee l sF iogfu rteh e1 )btuhi ladti nags . At the basement level, the model and the building were free to comınunicate with an extended f larly, the second and third levels freely c o ı nl ıonourn ai craetae.d Swi mi tih coınparatively large floor areas, although smaller than the bF raosı enmteh ne t . fourth level upward to the enclosing glass sky lisigohlat,tetdhe atrium was f j ace nt frloomorstheb ya d a combination of walls and fixed glazing. r,,GJa. •< .. D o First, they significantly adei l ruot es oal sn,dt hdei srpeebrse t h e y v o iding the appeara p n r c o e f concentration rec tSioencowncitlh, -tinhethe spalucce. y tarearions oal s pwo ri tt hi oi nn d t o o h f e e t a hni e r - Fırst Floor Second F1oor - Atthe upper portion of steherieesnoclosing walls, a f i a n n g d s w co e n r n e e e x in c h c t a e o u d r s p t t o o o rp v a e t a e n r d i able speed fans. At the lowest level, a supply wi n al es t i dn si rteacl l teedd, au lps ow aursd ing a variable speed fan . . •spoluınıneeo ancl deliver f theın to the exhaust systeın. Unfortunately, in the real-world f a n c a t r u io al , l this ai irrep l us cmee y does the same thing to the f ucts. Specifi ir c e a l p l yro , c i l t scatters the fire proc ub cu ti lsc l itnhgr oaun gc l hcol eupt r itvhel e s - □ Third 811d Fourth Ftoors -,,... - Aool $ky1ight ...... -K---- o □ o □ o □ o □ o□ o□ 00 □□ CDCDOJ .., � ın1erio, Elevation East 00 OD □□ O□ oo oo □□ o□ CDı:Dtl- -ln-ıe-rio-r ıEle_vaııi -on Wesl F"ıguıe 1. Plans and sections of scale model. ınıerio, Elevaıion North lnlerio< Eıevaı;on Soulh oT hne as cFa rl ion gu dwea smboa sdeedl because buoyancy twh aes ddeet eermmei ndi ntgo pbae rinagmbeetehri.n dT htehisrcehaosoi cne 109
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