From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001 From: priyanka Date: Wed, 24 Jun 2015 15:03:17 +0530 Subject: initial commit / add all books --- 1073/CH3/EX3.28/3_28.sce | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100755 1073/CH3/EX3.28/3_28.sce (limited to '1073/CH3/EX3.28/3_28.sce') diff --git a/1073/CH3/EX3.28/3_28.sce b/1073/CH3/EX3.28/3_28.sce new file mode 100755 index 000000000..2e0ad63ea --- /dev/null +++ b/1073/CH3/EX3.28/3_28.sce @@ -0,0 +1,31 @@ +clc; +clear; +//Example 3.28 +mair_dot=0.90 //[kg/s] +T1=283 //[K] +T2=366 //[K] +dT=(T1+T2)/2 //[K] +Di=12 //[mm] +Di=Di/1000 //[m] +G=19.9 //[kg/(sq m.s)] +mu=0.0198 //[mN.s/(sq m)] +mu=mu*10^-3 //[N.s/sq m] or [kg/(m.s)] +Nre=Di*G/mu //Reynolds number +//It is greater than 10^4 +k=0.029 //W/(m.K) +Cp=1 //[kJ/kg.K] +Cp1=Cp*10^3 //[J/kg.K] +Npr=Cp1*mu/k //Parndtl number +//Dittus-Boelter equation is +hi=0.023*(Nre^0.8)*(Npr^0.4)*k/Di //[W/sq m.K] +ho=232 //W/sq m.K +U=1/(1/hi+1/ho) //Overall heat transfer coefficient [W/m^2.K] +Q=mair_dot*Cp*(T2-T1) //kJ/s +Q=Q*10^3 //[J/s] or [W] +T=700 //[K] +dT1=T-T2 //[K] +dT2=T2-T1 //[K] +dTm=(dT1-dT2)/log(dT1/dT2) //[K] +//Q=U*A*dTm +A=Q/(U*dTm) //Area in sq m +printf("Heat transfer area of equipment is %f sq m",A); -- cgit