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Diffstat (limited to '534/CH8/EX8.7')
| -rw-r--r-- | 534/CH8/EX8.7/8_7_Microchannel.sce | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/534/CH8/EX8.7/8_7_Microchannel.sce b/534/CH8/EX8.7/8_7_Microchannel.sce new file mode 100644 index 000000000..3cf5ee7f2 --- /dev/null +++ b/534/CH8/EX8.7/8_7_Microchannel.sce @@ -0,0 +1,57 @@ +clear;
+clc;
+printf('FUNDAMENTALS OF HEAT AND MASS TRANSFER \n Incropera / Dewitt / Bergman / Lavine \n EXAMPLE 8.7 Page 525 \n'); //Example 8.5
+// Time needed to bring the reactants to within 1 degC of processing temperature
+
+//Operating Conditions
+T1 = 125+273; //[K] Chip Temperature 1
+T2 = 25+273; //[K] Chip Temperature 2
+Ti = 5+273; //[K] Inlet Temperature
+D = .01; //[m] Diameter
+L = .02; //[m] length
+delP = 500*10^3; //[N/m^2] Pressure drop
+//Dimensions
+a = 40*10^-6;
+b = 160*10^-6;
+s = 40*10^-6;
+
+//Table A.5 Ethylene Glycol Properties T = 288 K
+rho = 1120.2; //[kg/m^3] Density
+cp = 2359; //[J/kg.K] Specific Heat
+u = 2.82*10^-2; //[N.s/m^2] Viscosity
+k = 247*10^-3; //[W/m.K] Thermal Conductivity
+Pr = 269; //Prandtl number
+//Table A.5 Ethylene Glycol Properties T = 338 K
+rho2 = 1085; //[kg/m^3] Density
+cp2 = 2583; //[J/kg.K] Specific Heat
+u2 = .427*10^-2; //[N.s/m^2] Viscosity
+k2 = 261*10^-3; //[W/m.K] Thermal Conductivity
+Pr2 = 45.2; //Prandtl number
+
+P = 2*a+2*b; //Perimeter of microchannel
+Dh = 4*a*b/P; //Hydraulic Diameter
+
+um2 = 2/73*Dh^2/u2*delP/L; //[[m/s] Equation 8.22a
+Re2 = um2*Dh*rho2/u2; //Reynolds Number
+xfdh2 = .05*Dh*Re2; //[m] From Equation 8.3
+xfdr2 = xfdh2*Pr2; //[m] From Equation 8.23
+m2 = rho2*a*b*um2; //[kg/s]
+Nu2 = 4.44; //Nusselt Number from Table 8.1
+h2 = Nu2*k2/Dh; //[W/m^2.K] Convection Coeff
+Tc2 = 124+273; //[K]
+xc2 = m2/P*cp2/h2*2.303*log10((T1-Ti)/(T1-Tc2));
+tc2 = xc2/um2;
+
+um = 2/73*Dh^2/u*delP/L; //[[m/s] Equation 8.22a
+Re = um*Dh*rho/u; //Reynolds Number
+xfdh = .05*Dh*Re; //[m] From Equation 8.3
+xfdr = xfdh*Pr; //[m] From Equation 8.23
+m = rho2*a*b*um; //[kg/s]
+Nu = 4.44; //Nusselt Number from Table 8.1
+h = Nu*k/Dh; //[W/m^2.K] Convection Coeff
+Tc = 24+273; //[K]
+xc = m/P*cp/h*2.303*log10((T2-Ti)/(T2-Tc));
+tc = xc/um;
+
+printf("\n Temp [degC] %i %i\n\n Flow rate [m/s] %.3f %.3f\n Reynolds Number %.1f %.1f\n Hydrodynamic entrance Length [m] %.1e %.1e\n Thermal entrance Length [m] %.1e %.1e\n Mass Flow rate [kg/s] %.2e %.2e\n Convective Coeff [W/m^2.K] %.2e %.2e\n Transition Length [m] %.2e %.2e\n Required Time [s] %.3f %.3f",T2-273,T1-273,um,um2,Re,Re2,xfdh,xfdh2,xfdr,xfdr2,m,m2,h,h2,xc,xc2,tc,tc2);
+//END
\ No newline at end of file |