diff options
Diffstat (limited to '534/CH1/EX1.7')
-rw-r--r-- | 534/CH1/EX1.7/1_7_Cure_Temperature.sce | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/534/CH1/EX1.7/1_7_Cure_Temperature.sce b/534/CH1/EX1.7/1_7_Cure_Temperature.sce new file mode 100644 index 000000000..83187249c --- /dev/null +++ b/534/CH1/EX1.7/1_7_Cure_Temperature.sce @@ -0,0 +1,58 @@ +clear;
+clc;
+printf('FUNDAMENTALS OF HEAT AND MASS TRANSFER \n Incropera / Dewitt / Bergman / Lavine \n EXAMPLE 1.7 Page 30 \n')//Example 1.7
+// (a) Cure Temperature for h = 15 W/m^2
+// (b) Value of h for cure temp = 50 deg C
+
+Tsurr = 30+273; //[K] - Temperature of surrounding
+Tf = 20+273; //[K] - Temperature of Fluid Flow
+e=.5; // Emissivity of Surface
+a = .8; // Absorptivity of Surface
+G = 2000; //[W/m^2] - Irradiation falling on surface
+h=15; //[W/m^2.k] - Thermal Convectivity from plate to air
+stfncnstt=5.67*10^(-8); // [W/m^2.K^4] - Stefan Boltzmann Constant
+T=375; //[K] Value initially assumed for trial-error approach
+//Using Eq 1.3a & 1.7 and trial-and error approach of Newton Raphson
+while(1>0)
+f=((a*G)-(h*(T-Tf)+e*stfncnstt*(T^4 - Tsurr^4)));
+fd=(-h*T-4*e*stfncnstt*T^3);
+Tn=T-f/fd;
+if(((a*G)-(h*(Tn-Tf)+e*stfncnstt*(Tn^4 - Tsurr^4)))<=.01)
+ break;
+end;
+T=Tn;
+end
+
+printf("\n (a) Cure Temperature of Plate = %i degC\n",T-273);
+//solution (b)
+Treq=50+273;
+function[T]=Tvalue(h)
+ T=240;
+ while(1>0)
+ f=((a*G)-(h*(T-Tf)+e*stfncnstt*(T^4 - Tsurr^4)));
+ fd=(-h*T-4*e*stfncnstt*T^3);
+ Tn=T-f/fd;
+ if(((a*G)-(h*(Tn-Tf)+e*stfncnstt*(Tn^4 - Tsurr^4)))<=.01)
+ break;
+ end;
+ T=Tn;
+ end
+ funcprot(0)
+endfunction
+
+h = [2:.5:100];
+Tm = [1:1:197];
+for i=1:1:197;
+ Tm(i)=Tvalue(h(i));
+end
+
+T=Treq;
+hnew=((a*G)-(e*stfncnstt*(T^4 - Tsurr^4)))/(T-Tf);
+clf()
+xtitle("Graph Temp vs Convection Coeff", "h (W/m^2/K)", "T (degC)");
+x=[0 hnew hnew];
+y=[Treq-273 Treq-273 0];
+plot(h,Tm-273,x,y);
+legend("Plot","h at T = 50 degC");
+printf("\n (b) Air flow must provide a convection of = %i W/m^2.K", hnew);
+//END
\ No newline at end of file |