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SolutionsManual to accomparry Heat Transfer tenth edition J. P. Holman southernMethodisttJniversity Chapter I 1-1 LT- (39oox9-022 = (0.2x0.6) 625oc l-2 q _(0.035X85) -_ , 22f85 llt'm2 A 0.13 = g2,3g6 iln.^Z 1-3 , ^ cdT ll q- - _l...?1._ f u c- drc r-ax+b; x=0; dT -kw' nrT r-0.0375 x-0.3, r-A.0625 r = 0.083 3x + 0.0375 tuc|J @+lq3-s4o) rc(0.0g33x*AOW=-l_f \ " = o r=_- ( z o 4 ) ( _ 4 4 7 ) rce.og33) o.og,n*+ [ o.o3 lj )*=o ? q-2238 W 1{ q _ ( 0 . 2 8 X 3 7 5 - 9 5 )4 F ^ ^ A ffi-1s08 wl^z 1-5 A- w2 q - -k4nrzar d; (r =4n(2xl0u)(zl 1_ -4nk(ra-r) q-Y ri + 196)_ l . 6 l 7 w m -0rt85 mass evaporated = . 1'.u11= = e.gl3x l0-s kg/s 199'ooo - s.7az kglday rg ChapterI l:7 q 30+20 4-T* T-m= Zrlk ' httdo !(39) , r - 11.89W /m *arffi+er6rI l-8 Like manykindsof homespunadvice,this is badadvice.Alltypes of heattransfer; conductio4 convection,and radiationvary directly with area.The surfaceareaof the headis much lessthan that of the otherportion of the body andthuswill loselessheat. This may be shownexperimentallyby comparingexpozurein cold weatherwearing heavyclothing andno hat,to that wearinga heavyhat andonly undergarments! t-g q _ ( 0 . 1 6 1 X 2 0 0 - 1= 00 3 )Z Zw l ^ , A 0.05 1-10 Ar-: - KAAT q _ (roxlo-3#)tsoo) = 0.0125m - 1.25cm l-l I 4gzLr z.Ls8- (2.7)(o"l(*)1o.to '\12 )' LT = 0.632"C l-12 q-(5.669x lo-*)t(r o:n)4-6214l = 7 0 . 9g [ A ^2 l-13 =188 ry m- g =(5.669x lo-t)t(t 3n)4 - (698)41 A l-14 - (70)oJ = 704.8 W x 10-r)(+ox0.3 q = (s.669 ,2t(300)4 1-15 il. q - (5.669x tO-t)t7n)4 -Q7r4J - t.9t 4x104 wl*' b. q -(5.669x lo-r)ten)4 - (Til4I = (5.669xlo-tlrtro )4- Q:R\41 T P = 6 4 1K q - 8 4 7 4 - 3w l ^ t Reducedby 44.37o 3' ChaPter1 l-16 q - h A( T w-T p u i a ) FromTablet-z w h-3soo ;zJc q=(3500)rTd.L(40)=(3500)zr(0.025X3X40)=32987w q = mcoLTpaid \[ - (0-5kg/sX4180J/kg'oC)Af 32,987 LT=15.78oC l-17 hfs = 2257 kJ/kg kJ = 2'37 =2-37kw = 1 853 kJ/kg) S q = tuhfr= (3-78kg/hr)(2257 * r_z FromTable h_Tsoo $- q=hA(T*-Tpuia) - 100) 2370\{ - (7500x0.3)2(T* T* =965oC 1-18 q= LALT 3 x to4 Btu - hQ3z-zrz)"F ffi- h-1s00 +=85 hr'ft' 17 w oC ^2 ' 1-19 q =oa{t( T)a - (Tz)41 - (298)41 2000W - (5.669x l0-sX0.85X0.006X3)t(n)4 \=t233K 1-20 - 1'489x lOs g q+273)a t0-*Xt000 (5 .66gx m' dr4= A l-2r q - d t4 A ' ro^ 06 = (5 -66gx1o-8)74 T - 55 5 6K Chapter 1 r-22 -Tro\=(5.669 gtl4 -2934)=29.t9w q = oeAl(T1o x to-8;1o.oXazrX0.0af r-23 AT q=lAi= M(Ta-T-) - 4L) (1.4X315 - h(41- 38) 4.025 h-s|14 y m'.oc l-.25 1 0 0- T q_(t.6)'#_ ro(r*z_ro) T*, - 35.7oC q -10(35 .7 -10) -2s7 g m2 r-26 lt - 4.5 From Table l-2 y for LT: 30oC mt.oc - 12.15 q - uALT= (4.5X0,3)2(rO) V,' Conduqlion q-kA+ Ar W frfor air = 0.03 - m-oC _ 3.24W q,,,_(o.o3xo.3)2(30) 0^025 1-21 ^r_ (lsoo)(H) - l,2soF 25 7".100-1.25-98.75oF 1t8 700- (l r)(T* - 30) Tw = 93'6oC Chapter 1 r-29 Q=Qconv*Qrad qconv = hA(Tr-T*) FromTablel-2 ft = 180+- m'.oc -30) = 4807 y length =(1S0)z(0.05)0X200 econv m -Tza) = oeAl(Tta Qrad = (5.669x to-8xo.z)z(0.05X1) (4:a4 -2834) =2 7 2 I t" n g th m = 48O7 + 272=5079 Y Qtotat m Most heattransferis by convection. 1-30 Q=flconv*Qrad -T*) 4co