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Diffstat (limited to '534/CH12/EX12.5/12_5_Diffuse_emitter.sce')
-rw-r--r-- | 534/CH12/EX12.5/12_5_Diffuse_emitter.sce | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/534/CH12/EX12.5/12_5_Diffuse_emitter.sce b/534/CH12/EX12.5/12_5_Diffuse_emitter.sce new file mode 100644 index 000000000..8d2f40319 --- /dev/null +++ b/534/CH12/EX12.5/12_5_Diffuse_emitter.sce @@ -0,0 +1,45 @@ +clear;
+clc;
+printf('FUNDAMENTALS OF HEAT AND MASS TRANSFER \n Incropera / Dewitt / Bergman / Lavine \n EXAMPLE 12.5 Page 748 \n')// Example 12.5
+
+// Total hemispherical emissivity
+// Total emissive Power
+// Wavelength at which spectral emissive power will be maximum
+
+T = 1600 ;//[K] temperature of surface
+wl1 = 2 ;//[micro-m] wavelength 1
+wl2 = 5 ;//[micro-m] wavelength 2
+stfncnstt = 5.67*10^-8; //[W/m^2.K^4] Stefan-Boltzmann constant
+// From the given graph of emissivities
+e1 = .4;
+e2 = .8;
+//From Equation 12.26 Black Body Radiation
+Eb = stfncnstt*T^4; //[W/m^2]
+
+//Solution (A)
+//From Table 12.1 as wl1*T = 2*1600 (micro-m.K)
+F02 = .318;
+//From Table 12.1 as wl2*T = 5*1600 (micro-m.K)
+F05 = .856;
+//From Equation 12.36
+e = e1*F02 + e2*[F05 - F02];
+
+//Solution (B)
+//From equation 12.35
+E = e*Eb;
+
+//Solution (C)
+//For maximum condition Using Weins Law
+consttmax = 2898 ;//[micro-m.K]
+wlmax = consttmax/T;
+
+//equation 12.32 with Table 12.1
+E1 = %pi*e1*.722*10^-4*stfncnstt*T^5;
+
+E2 = %pi*e2*.706*10^-4*stfncnstt*T^5;
+
+printf("\n (a) Total hemispherical emissivity = %.3f \n (b) Total emissive Power = %i kW/m^2 \n (c) Emissive Power at wavelength 2micro-m is greater than Emissive power at maximum wavelength \n i.e. %.1f kW/m^2 > %.1f kW/m^2 \n Thus, Peak emission occurs at %i micro-m",e,E/1000,E2/1000,E1/1000,wl1);
+//END
+
+
+
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