{VERSION 3 0 "SUN SPARC SOLARIS" "3.0" }
{USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 
1 0 0 0 0 }{CSTYLE "2D Math" -1 2 "Times" 0 1 0 0 0 0 0 0 2 0 0 0 0 0 
0 }{CSTYLE "2D Output" 2 20 "" 0 1 0 0 255 1 0 0 0 0 0 0 0 0 0 }
{PSTYLE "Normal" -1 0 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 
0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "Maple Output" 0 11 1 
{CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 }3 3 0 -1 -1 -1 0 0 
0 0 0 0 -1 0 }}
{SECT 0 {EXCHG {PARA 0 "" 0 "" {TEXT -1 228 "A 1/12 inch diameter meta
l wire is placed in still air at 66 deg F.  Determine the rate of heat
 generation required to maintain the surface temperature of the wire a
t 1734 deg F.  The heat loss due to radiation may be neglected." }}}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 8 "restart;" }}}{EXCHG {PARA 0 "
" 0 "" {TEXT -1 67 "The mean film temperature at the air wire interfac
e is given below." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "
> " 0 "" {MPLTEXT 1 0 52 "To:=1734*F; Tinf:=66*F; Tf:=(To+Tinf)/2; bet
a:=1/Tf;" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%#ToG,$%\"FG\"%M<" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6#>%%TinfG,$%\"FG\"#m" }}{PARA 11 "" 1 "
" {XPPMATH 20 "6#>%#TfG,$%\"FG\"$+*" }}{PARA 11 "" 1 "" {XPPMATH 20 "6
#>%%betaG,$*&\"\"\"F'%\"FG!\"\"#\"\"\"\"$+*" }}}{EXCHG {PARA 0 "" 0 "
" {TEXT -1 42 "Other fluid properties of air at 900 deg F" }}}{EXCHG 
{PARA 0 "> " 0 "" {MPLTEXT 1 0 88 "mu:=0.0846*lbm/hr/ft; k:=0.0320*Btu
/hr/ft/F; Cp:=0.260*Btu/lbm/F; rho:=0.02374*lbm/ft^3;" }}{PARA 11 "" 
1 "" {XPPMATH 20 "6#>%#muG,$*&%$lbmG\"\"\"*&%#hrG\"\"\"%#ftG\"\"\"!\"
\"$\"$Y)!\"%" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%\"kG,$*&%$BtuG\"\"\"
*(%#hrG\"\"\"%#ftG\"\"\"%\"FG\"\"\"!\"\"$\"$?$!\"%" }}{PARA 11 "" 1 "
" {XPPMATH 20 "6#>%#CpG,$*&%$BtuG\"\"\"*&%$lbmG\"\"\"%\"FG\"\"\"!\"\"$
\"$g#!\"$" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%$rhoG,$*&%$lbmG\"\"\"*$
)%#ftG\"\"$F(!\"\"$\"%uB!\"&" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 16 "O
ther parameters" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 55 "dia:=1/1
2/12*ft; deltaT:=To-Tinf; g:=4.17*10^8*ft/hr^2;" }}{PARA 11 "" 1 "" 
{XPPMATH 20 "6#>%$diaG,$%#ftG#\"\"\"\"$W\"" }}{PARA 11 "" 1 "" 
{XPPMATH 20 "6#>%'deltaTG,$%\"FG\"%o;" }}{PARA 11 "" 1 "" {XPPMATH 20 
"6#>%\"gG,$*&%#ftG\"\"\"*$)%#hrG\"\"#F(!\"\"$\"++++qT!\"\"" }}}{EXCHG 
{PARA 0 "" 0 "" {TEXT -1 22 "Compute Prandtl number" }}}{EXCHG {PARA 
0 "> " 0 "" {MPLTEXT 1 0 12 "Pr:=Cp*mu/k;" }}{PARA 11 "" 1 "" 
{XPPMATH 20 "6#>%#PrG$\"+++vto!#5" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 
22 "Compute Grashof number" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 
37 "Gr:=(rho^2*beta*g*dia^3*deltaT)/mu^2;" }}{PARA 11 "" 1 "" 
{XPPMATH 20 "6#>%#GrG$\"+pu3Q?!\")" }}}{EXCHG {PARA 0 "" 0 "" {TEXT 
-1 88 "Compute Gr x Pr.  If greater than 10^4 can use Eq. 13.5-3 to Ap
proximate Nusselt number." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 
12 "GrPr:=Gr*Pr;" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%%GrPrG$\"+u.$4S
\"!\")" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 107 "GrPr is much smaller t
han 10^4.  Must use experimental data and polynomial fit to determine \+
Nusselt number." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 15 "readlib(
log10):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 21 "log(GP):=log10(G
rPr);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>-%$logG6#%#GPG$\"+^lTY6!\"*
" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 77 "log(Nu):=-5E-5*(l(GP))^
4+.0003*(l(GP))^3+.012*(l(GP))^2+.124*(l(GP))+.0285;  " }}{PARA 11 "" 
1 "" {XPPMATH 20 "6#>-%$logG6#$\"+y+UP:!\"*$\"+%[Dz'=!#5" }}}{EXCHG 
{PARA 0 "> " 0 "" {MPLTEXT 1 0 17 "Nu_m:=10^log(Nu);" }}{PARA 11 "" 1 
"" {XPPMATH 20 "6#>%%Nu_mG$\"+y+UP:!\"*" }}}{EXCHG {PARA 0 "" 0 "" 
{TEXT -1 101 "From the definition of the Nusselt number we can determi
ne the mean Heat Transfer Coefficient:  (hm)." }}}{EXCHG {PARA 0 "> " 
0 "" {MPLTEXT 1 0 15 "hm:=Nu_m*k/dia;" }}{PARA 11 "" 1 "" {XPPMATH 20 
"6#>%#hmG,$*&%$BtuG\"\"\"*(%#hrG\"\"\")%#ftG\"\"#F(%\"FG\"\"\"!\"\"$\"
+?<V%3(!\"*" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 81 "The rate of heat l
oss can be determined from Eq. 13.1-1.  Q = hm * Area * deltaT." }}}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 26 "Q = hm*3.14159*dia*deltaT;" 
}}{PARA 11 "" 1 "" {XPPMATH 20 "6#/%\"QG,$*&%$BtuG\"\"\"*&%#hrG\"\"\"%
#ftG\"\"\"!\"\"$\"+m1.yD!\"(" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 211 "
Compute the surface temperature of a 1/12 inch diameter resistance wir
e generating heat at the rate of 236.77 Btu/hr per foot length.  The a
mbient air temperature is 66 deg F.  Neglect the radiation heat loss. \+
 " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 
279 "The solution is approached through an iterative process.  An init
ial value of ther surface temperature is assumed and the heat rate teq
uired ti maintain this temperature is calculated.  This procedure is r
epeated until the calculated value of the heat rate equal the given va
lue." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" 
{MPLTEXT 1 0 8 "restart;" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 82 "As a \+
first estimate, guess the surface temperature of the wire to be 1700 d
eg F.  " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 13 "Temp := 1600;" }
}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%%TempG\"%+;" }}}{EXCHG {PARA 0 "> \+
" 0 "" {MPLTEXT 1 0 0 "" }}}}{MARK "28 0 0" 0 }{VIEWOPTS 1 1 0 1 1 
1803 }