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Diffstat (limited to '1073/CH5/EX5.11')
| -rwxr-xr-x | 1073/CH5/EX5.11/5_11.sce | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/1073/CH5/EX5.11/5_11.sce b/1073/CH5/EX5.11/5_11.sce new file mode 100755 index 000000000..6bb05fb5f --- /dev/null +++ b/1073/CH5/EX5.11/5_11.sce @@ -0,0 +1,41 @@ +clc;
+clear;
+//Example 5.11
+mw_dot=1720; //water in [kg/h]
+t1=293 ; //[K]
+t2=318 ; //[K]
+Cpw=4.28; //[kJ/kg.K]
+Q=mw_dot*Cpw*(t2-t1) //[kJ/h]
+Q=Q*1000/3600 //W
+lambda=2230; //[kJ/kg]
+dT1=90 ; //[K]
+dT2=65 ; //[K]
+dTlm=(dT1-dT2)/log(dT1/dT2) //[K]
+
+//Calculation of inside heat transfer coefficient
+Di=0.0225; //[m]
+u=1.2 ; //[m/s]\
+rho=995.7 ; //[kg/m^3]
+v=0.659*10^-6 //[m/s]
+mu=v*rho //[kg/m.s]
+Nre=Di*u*rho/mu //reynolds number
+Cp=Cpw*1000 //[J/kg.K]
+k=2.54 ; //[kJ/h.m.K]
+k=k*1000/3600 //[W/m.K]
+Npr=Cp*mu/k //Prandtl number
+Nnu=0.023*Nre^0.8*Npr^0.4 //Nusselt number
+hi=k*Nnu/Di //[W/sq m.K]
+ho=19200 //[kJ/h.m^2.K]
+ho=ho*1000/3600 //[W/m^2.K]
+Do=0.025 //[m]
+Dw=(Do-Di)/log(Do/Di) //[m]
+x=(Do-Di)/2 //[m]
+kt=460 //For tube wall material [kJ/h.m.K]
+kt=kt*1000/3600 //[W/m.K]
+Uo=1/(1/ho+(1/hi)*(Do/Di)+(x/kt)*(Do/Dw)) //[W/sq m.K]
+//Q=Uo*Ao*dTlm
+Ao=Q/(Uo*dTlm) //[sq m]
+L=4 //Tube length in [m]
+n=Ao/(%pi*Do*L) //[Number of tubes]
+n=round(n) //Approximate
+printf("\n Number of tubes reuired= %d",n);
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