diff options
Diffstat (limited to '1226/CH20/EX20.38/EX20_38.sce')
-rwxr-xr-x | 1226/CH20/EX20.38/EX20_38.sce | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/1226/CH20/EX20.38/EX20_38.sce b/1226/CH20/EX20.38/EX20_38.sce new file mode 100755 index 000000000..51af04eeb --- /dev/null +++ b/1226/CH20/EX20.38/EX20_38.sce @@ -0,0 +1,32 @@ +clc;funcprot(0);//EXAMPLE 20.38
+// Initialisation of Variables
+ma=528;.............//Air flow in kg/min
+m=ma/60;.............//Air flow in kg/s
+p1=1;........//Inlet pressure in bar
+t1=293;............//Inlet temperature in bar
+N=20000;..............//Compressor rpm
+etaisen=0.8;.........//Isentropic efficiency
+po1=1;.........//Static pressure in bar
+p02=4;...........//Final total pressure in bar
+C1=145;.........//Velocity of air when entering the impeller in m/s
+rwt=0.9;..........//Ratio of whirl speed to tip speed
+dh=0.12;........//Hub diameter in m
+cp=1.005;...........//Specific heat at constant pressure in kJ/kgK
+ga=1.4;............//Ratio of specific heats
+R=287;..............//Gas constant for air in kJ/kgK
+//Calculations
+t01=t1+((C1*C1)/(2*cp*1000));..........//Stagnation temperature at the inlet to the machine in K
+p01=p1*((t01/t1)^(ga/(ga-1)));.....//Stagnation pressure at the inlet to the machine in bar
+t021=t01*((p02/p01)^((ga-1)/ga));
+deltisen=t021-t01;.........//Isentropic rise in temperature in K
+delt=round(deltisen/etaisen);........//Actual rise in temperature
+disp(delt,"Actual rise in temperature:")
+wc=cp*delt;.........//Work consumed by compressor in kJ/kg
+Cbl2=sqrt(wc*1000/rwt);
+d2=Cbl2*60/(%pi*N);..........//Tip diameter of the impeller in m
+disp(d2*100,"Tip diameter of the impeller in cm:")
+P=m*wc;............//Power required in kW
+disp(P,"Power required in kW:")
+rho1=(p1*10^5)/(R*t1);.......//Density at entry in kg/m^3
+d1=sqrt(((m*4)/(C1*rho1*%pi))+(dh^2));.......//Eye diameter in m
+disp(d1*100,"Diameter of the eye in cm:")
|