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Diffstat (limited to '2510/CH18/EX18.22')
| -rwxr-xr-x | 2510/CH18/EX18.22/Ex18_22.sce | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/2510/CH18/EX18.22/Ex18_22.sce b/2510/CH18/EX18.22/Ex18_22.sce new file mode 100755 index 000000000..f2a0c1083 --- /dev/null +++ b/2510/CH18/EX18.22/Ex18_22.sce @@ -0,0 +1,26 @@ +//Variable declaration: +//From example 18.21: +m = 144206 //Mass flow rate of flue gas (lb/h) +cp = 0.3 //Average heat capacities of the flue gas (Btu/lb F) +T1 = 2050 //Initial temperature of gas ( F) +T2 = 180 //Final temperature of gas ( F) +T3 = 60 //Ambient air temperature ( F) +U = 1.5 //Overall heat transfer coefficient for cooler (Btu/h.ft^2. F) +MW = 28.27 //Molecular weight of gas +R = 379 //Universal gas constant (psia.ft^3/lbmol. R) +v = 60 //Duct or pipe velcity at inlet (2050 F) (ft/s) +pi = %pi + +//Calculation: +Q = m*cp*(T1-T2) //Heat duty (Btu/h) +DTlm = ((T1-T3)-(T2-T3))/log((T1-T3)/(T2-T3)) //Log-mean temperature difference ( F) +A1 = round(Q * 10**-5)/10**-5/(U*round(DTlm)) //Radiative surface area (ft^2) +q = m*R*(T1+460)/(T3+460)/MW //Volumetric flow at inlet (ft^3/h) +A2 = q/(v*3600) //Duct area (ft^2) +D = sqrt(A2*4/pi) //Duct diameter (ft) +L = A1/(pi*D) //Length of required heat exchange ducting (ft) +A1 = round(A1*10**-1)/10**-1 + +//Result: +printf(" The radiative surface area required is : %f ft^2 .",A1) +printf(" The length of required heat exchange ducting is : %.0f ft .",L) |