diff options
Diffstat (limited to '2223/CH11/EX11.6/Ex11_6.sce')
-rwxr-xr-x | 2223/CH11/EX11.6/Ex11_6.sce | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/2223/CH11/EX11.6/Ex11_6.sce b/2223/CH11/EX11.6/Ex11_6.sce new file mode 100755 index 000000000..92a67d559 --- /dev/null +++ b/2223/CH11/EX11.6/Ex11_6.sce @@ -0,0 +1,75 @@ +// scilab Code Exa 11.6 General Swirl Distribution axial compressor
+
+Rm=0.5; // Degree of reaction
+dm=36/100; // Mean Blade ring diameter in m
+rm=dm/2;
+N=18e3; // rotor Speed in RPM
+h=6/100; // blade height at entry in m
+dh=dm-h;
+dt=dm+h;
+cx=180; // Axial velocity in m/s
+alpha_1m=25; // air angle at rotor and stator exit
+alpha_2m=54.820124;
+um=%pi*dm*N/60;
+omega=um/rm;
+rh=dh/2;
+rt=dt/2;
+uh=omega*rh;
+ut=omega*rt;
+
+// part(a) rotor blade air angles
+c_theta1m=cx*tand(alpha_1m);
+c_theta2m=cx*tand(alpha_2m);
+a=0.5*(c_theta1m+c_theta2m)
+b=rm*(c_theta2m-c_theta1m)*0.5;
+c_theta1h=a-(b/rh);
+c_theta1t=a-(b/rt);
+K1=cx^2+(2*(a^2)*((b/(a*rm))+log(rm)));
+cx1h=sqrt(K1-(2*(a^2)*((b/(a*rh))+log(rh))));
+cx1t=sqrt(K1-(2*(a^2)*((b/(a*rt))+log(rt))));
+
+c_theta2h=a+(b/rh);
+c_theta2t=a+(b/rt);
+K2=cx^2+(2*(a^2)*(log(rm)-(b/(a*rm))));
+cx2h=sqrt(K2-(2*(a^2)*(log(rh)-(b/(a*rh)))));
+cx2t=sqrt(K2-(2*(a^2)*(log(rt)-(b/(a*rt)))));
+disp("(a) the rotor blade air angles are")
+// for hub section
+alpha1h=atand(c_theta1h/cx1h);
+alpha2h=atand(c_theta2h/cx2h);
+disp("for hub section")
+beta1h=atand((uh/cx1h)-tand(alpha1h));
+beta2h=atand((uh/cx2h)-tand(alpha2h));
+disp("degree",beta1h,"beta1h=")
+disp("degree",beta2h,"beta2h=")
+
+// for tip section
+alpha1t=atand(c_theta1t/cx1t);
+alpha2t=atand(c_theta2t/cx2t);
+disp("for tip section")
+beta1t=atand((ut/cx1t)-tand(alpha1t));
+beta2t=atand((ut/cx2t)-tand(alpha2t));
+disp("degree",beta1t,"beta1t= ")
+disp("degree",beta2t,"beta2t= ")
+
+// part(b) specific work
+w=2*omega*b;
+disp("kJ/kg",w*1e-3,"(b)specific work is")
+
+// part(c) the loading coefficients
+disp("(c)the loading coefficients are")
+shi_h=w/(uh^2);
+disp(shi_h,"shi_h=")
+shi_m=w/(um^2);
+disp(shi_m,"shi_m=")
+shi_t=w/(ut^2);
+disp(shi_t,"shi_t=")
+
+// part(c) degrees of reaction
+disp("(d)Degrees of reaction are")
+Rh=((cx1h^2)*(secd(beta1h)^2)-(cx2h^2)*(secd(beta2h)^2))*100/(2*w);
+Rt=((cx1t^2)*(secd(beta1t)^2)-(cx2t^2)*(secd(beta2t)^2))*100/(2*w);
+disp("%",Rh,"Rh=")
+disp("%",Rm*100,"Rm=")
+disp("%",Rt,"Rt=")
+disp("Comment: book contains wrong calculation for Rt value")
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