clc
clear
//input data
b2=10//Rotor blade air angle at exit in degree
Dt=0.6//The tip diameter in m
Dh=0.3//The hub diameter in m
N=960//The speed of the fan in rpm
P=1//Power required by the fan in kW
pi=0.245//The flow coefficient
P1=1.02//The inlet pressure in bar
T1=316//The inlet temperature in K
R=287//The universal gas constant in J/kg.K
Cp=1.005//The specific heat of air at constant pressure in kJ/kg.K
r=1.4//The ratio of specific heats of air
g=9.81//Acceleration due to gravity in m/s^2

//calculations
A=(3.141/4)*((Dt^2)-(Dh^2))//Area of the fan at inlet in m^2
Dm=(Dt+Dh)/2//The mean rotor diameter in m
U=(3.141*Dm*N)/60//The mean blade speed in m/s
Ca=pi*U//The axial velocity in m/s
Q=A*Ca//The flow rate of air in m^3/s
d=(P1*10^5)/(R*T1)//Density of air in kg/m^3
dPst=((d*(U^2)*(1-((pi*tand(b2))^2)))/2)*((10^5)/(g*(10^3)))*10^-5//Static pressure across the stage in m W.G
Wm=U*(U-(Ca*tand(b2)))//Work done per unit mass in J/kg
m=d*Q//Mass flow rate in kg/s
W=m*Wm//Work done in W
no=W/(P*10^3)//Overall efficiency 

//output
printf('(a)THe flow rate is %3.3f m^3/s\n(b)Static pressure rise across the stage is %3.3f m W.G\n(c)The overall efficiency is %3.4f',Q,dPst,no)