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+clc;
+rp=4; // Overall pressure ratio
+m=3; // mass flow rate in kg/s
+eff_pc=0.88; // Polytropic efficiency
+Del_Tstage=25; // The stagnation temperature pressure rise in kelvin
+c1=165; // Absolute velocity in m/s
+alpha_1=20; // air angle from axial direction in degree
+wf=0.83; // Workdone factor
+D=18; // Mean diameter of the last stage rotor in cm
+P01=1.01; // Ambient pressure in bar
+T01=288; // Ambient temperature in kelvin
+Cp=1005; // Specific heat in J/kg K
+r=1.4; // Specific heat ratio
+R=287; // Characteristic gas constant in J/kg K
+
+n=1/(1-(r-1)/(r*eff_pc));
+T02=T01*(rp)^((n-1)/n); // Total pressure at stage 2
+Del_Toverall= T02-T01; // Overall temperature difference
+Ns=Del_Toverall/Del_Tstage; // Number of stages
+eff_C=((rp^((r-1)/r)-1)/(rp^((r-1)/(r*eff_pc))-1));// Efficiency of compressor
+rp1=(1+(eff_C*Del_Tstage/T01))^(r/(r-1)); // Pressure ratio acrocc first stage
+Del_Tstage1=Del_Toverall/Ns; // Temperature rise across stage 1
+T0ls=T02-Del_Tstage1; // Temperature at inlet to last stage
+rpls=(1+(eff_C*Del_Tstage1/T0ls))^(r/(r-1)); // Pressure ratio acrocc last stage
+// For symmetrical blade, R=0.5
+beta_2=alpha_1;
+ca=c1*cosd (alpha_1); // Axial velocity
+beta_1=atand(sqrt(((Cp*Del_Tstage1/(wf*ca))/ca)+(tand(beta_2))^2)); // blade angle
+u=ca*(tand(beta_1)+tand(beta_2)); // mean velocity of blade
+N=60*u/(3.14*D*10^-2*60); // Speed in rps
+Po=rp/rpls; // Total pressure at inlet to the last stage
+T0=T0ls; // Total temperature to the last stage
+Tst=T0-c1^2/(2*Cp); // Static temperature
+Pst=Po/(T0/Tst)^((r-1)/r); // Static pressure
+row=(Pst*10^5)/(R*Tst); // Density
+h=m/(ca*row*3.14*D*10^-2);// Length of last stage
+
+disp (Ns,"Number of stages = ");
+disp (rp1,"Pressure ratio across first stage = ");
+disp (" (roundoff error)",rpls,"Temperature at inlet to last stage = ");
+disp ("degree (roundoff error)",beta_1,"beta1=" );
+disp ("rps (roundoff error)",N,"Speed = ");
+disp ("cm (roundoff error)",h*100,"Length of last stage = ");