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 --- 1955/CH5/EX5.3/example3.sce | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100755 1955/CH5/EX5.3/example3.sce (limited to '1955/CH5/EX5.3/example3.sce') diff --git a/1955/CH5/EX5.3/example3.sce b/1955/CH5/EX5.3/example3.sce new file mode 100755 index 000000000..1a04b3ce5 --- /dev/null +++ b/1955/CH5/EX5.3/example3.sce @@ -0,0 +1,43 @@ +clc +clear +//input data +P1=5//Input pressure of steam in bar +P2=3//Exhaust pressure of steam in bar +C0=75//Carry over velocity of steam in m/s +a1=20//Nozzle angle in degree +UC1=0.4//The direction of blade rotation and blade speed ratio +b2=20//Blade exit angle in degree +m=2.5//Steam flow rate in kg/s +W=206//Power Output of the stage in kW +Nn=0.9//Efficiency of the nozzle + +printf('Assuming isentropic expansion the enthalpy drop can be found from steam table\n\nThe following values are obtained from steam tables') + +h1=2747.5//Enthalpy at initial pressure in kJ/kg +s1=6.819//Entropy at initial pressure in kJ/kg.K +s2=s1//Entropy at final pressure in kJ/kg.K +sfp2=1.647//Entropy of fliud at final pressure in kJ/kg.K +sfgp2=5.367//Entropy of fliud-gas mixture at final pressure in kJ/kg.K +hfg=2170.1//Enthalpy of fliud-gas mixture in kJ/kg +hf=551.5//Enthalpy of fliud in kJ/kg + +printf('\n\nThe scale of the velocity vector diagram is 1:50\n\nThe following values are obtained from the velocity vector diagram') + +W1=280//Relative velocity at inlet in m/s +W2=240//Relative velocity at exit in m/s + +//calculations +x2=(s2-sfp2)/sfgp2//The percentage of wet steam +h2s=hf+(x2*hfg)//The isentropic enthalpy at the second stage in kJ/kg +dhs=h1-h2s//Isentropic heat drop in kJ/kg +C1=((2000*Nn*dhs)+(C0^2))^(1/2)//Velocity of steam at exit from nozzle in m/s +U=UC1*C1//Blade speed in m/s +Wx1Wx2=(W*10^3)/(m*U)//The sum of whirl components of velocity in m/s +Ndia=(U*Wx1Wx2)/((C1^2)/2)//Diagram efficiency +RV=W2/W1//Relative velocity ratio +E=dhs+((C0^2)/2000)//Energy supplied per kg in kJ/kg +Ns1=(U*Wx1Wx2)/(E*10^3)//Stage efficiency +Ns2=Ndia*Nn//Stage efficiency in other method + +//output +printf('\n\n(a)Velocity of steam at exit from nozzle is %3.2f m/s\n(b)Diagram efficiency is %3.4f\n(c)Relative velocity ratio is %3.3f\n(d)\n Stage efficiency in method 1 is %3.4f\n Stage efficiency in method 2 is %3.4f',C1,Ndia,RV,Ns1,Ns2) -- cgit