initial commit / add all books

9 files changed, 334 insertions, 0 deletions

diff --git a/3433/CH10/EX10.10/Ex10_10.sce b/3433/CH10/EX10.10/Ex10_10.sce
new file mode 100644
index 000000000..7a88d4ee6
--- /dev/null
+++ b/3433/CH10/EX10.10/Ex10_10.sce
@@ -0,0 +1,50 @@
+clear;

+clc;

+funcprot(0);

+

+//function to calculate values of blade chord and radius (optimum conditions)

+function [j,lamda,r,l] = fun(phi)

+    lamda = 1-cos(phi*%pi/180);

+    j = sin(phi*%pi/180)*(2*cos(phi*%pi/180)-1)/(1+2*cos(phi*%pi/180))/(lamda);

+    r = 3*j;

+    l = 8*%pi*j*lamda;

+endfunction

+

+//given data

+D = 30;//tip diameter in m

+J = 5.0;//tip-speed ratio

+Z = 3;//in m

+CL = 1.0;

+

+//Calculations

+phi1 = 30;//in deg

+phi2 = 20;//in deg

+phi3 = 15;//in deg

+phi4 = 10;//in deg

+phi5 = 7.556;//in deg

+//Values of blade chord and radius (optimum conditions)

+[j1,lamda1,r1,l1] = fun(phi1);

+[j2,lamda2,r2,l2] = fun(phi2);

+[j3,lamda3,r3,l3] = fun(phi3);

+[j4,lamda4,r4,l4] = fun(phi4);

+[j5,lamda5,r5,l5] = fun(phi5);

+

+printf('Values of blade chord and radius(optimum conditions):');

+printf('\n -----------------------------------------------------------------');

+printf('\n phi(deg)      j           4flamda            r(m)           l(m)');

+printf('\n -----------------------------------------------------------------');

+printf('\n %d        %.2f             %.3f         %.1f              %.3f',phi1,j1,4*j1*lamda1,r1,l1);

+printf('\n %d        %.2f             %.3f         %.2f             %.3f',phi2,j2,4*j2*lamda2,r2,l2);

+printf('\n %d        %.2f             %.3f         %.2f             %.3f',phi3,j3,4*j3*lamda3,r3,l3);

+printf('\n %d        %.3f            %.4f        %.1f             %.3f',phi4,j4,4*j4*lamda4,r4,l4);

+printf('\n %.3f       %d              %.4f         %d              %.3f',phi5,ceil(j5),4*j5*lamda5,ceil(r5),l5);

+printf('\n -----------------------------------------------------------------');

+

+l_R = [l1,l2,l3,l4,l5]/(0.5*D);

+r_R = [r1,r2,r3,r4,r5]/(0.5*D);    

+plot(r_R,l_R);

+xlabel("r/R",'fontsize',3);

+ylabel("l/R",'fontsize',3);

+title("Optimal variation of chord length with radius",'fontsize',3);

+

+//there are very small errors in the ansers given in textbook

diff --git a/3433/CH10/EX10.2/Ex10_2.sce b/3433/CH10/EX10.2/Ex10_2.sce
new file mode 100644
index 000000000..5e466c2a8
--- /dev/null
+++ b/3433/CH10/EX10.2/Ex10_2.sce
@@ -0,0 +1,14 @@
+clear;

+clc;

+funcprot(0);

+

+//given data

+a_ = 1/3;

+

+//Calculations

+R2_R1 = 1/(1-a_)^0.5;

+R3_R1 = 1/(1-2*a_)^0.5;

+R3_R2 = ((1-a_)/(1-2*a_))^0.5;

+

+//Results

+printf('R2/R1 = %.3f\n R3/R1 = %.3f\n R3/R2 = %.3f',R2_R1,R3_R1,R3_R2);

diff --git a/3433/CH10/EX10.3/Ex10_3.sce b/3433/CH10/EX10.3/Ex10_3.sce
new file mode 100644
index 000000000..fb2feaec5
--- /dev/null
+++ b/3433/CH10/EX10.3/Ex10_3.sce
@@ -0,0 +1,19 @@
+clear;
+clc;
+funcprot(0);
+
+//given data
+d = 30;//tip diameter in m
+cx1 = 7.5;//in m/s
+cx2 = 10;//in m/s
+rho = 1.2;//in kg/m^3
+a_ = 1/3;
+
+//Calculations
+P1 = 2*a_*rho*(%pi*0.25*d^2)*(cx1^3)*(1-a_)^2;
+P2 = 2*a_*rho*(%pi*0.25*d^2)*(cx2^3)*(1-a_)^2;
+
+
+//Results
+printf('(i)With cx1 = %.1f m/s, P = %d kW.',cx1,P1/1000);
+printf('\n(ii)With cx1 = %d m/s, P = %.1f kW.',cx2,P2/1000);
diff --git a/3433/CH10/EX10.4/Ex10_4.sce b/3433/CH10/EX10.4/Ex10_4.sce
new file mode 100644
index 000000000..df9740dba
--- /dev/null
+++ b/3433/CH10/EX10.4/Ex10_4.sce
@@ -0,0 +1,18 @@
+clear;

+clc;

+funcprot(0);

+

+//given data

+P = 20;//power required in kW

+cx1 = 7.5;//steady wind speed in m/s

+rho = 1.2;//density in kg/m^3

+Cp = 0.35;

+eta_g = 0.75;//output electrical power

+eff_d = 0.85;//electrical generation efficiency

+

+//Calculations

+A2 = 2*P*1000/(rho*Cp*eta_g*eff_d*cx1^3);

+D2 = sqrt(4*A2/%pi);

+

+//Results

+printf('The diameter = %.1f m.',D2);

diff --git a/3433/CH10/EX10.5/Ex10_5.sce b/3433/CH10/EX10.5/Ex10_5.sce
new file mode 100644
index 000000000..d0806f999
--- /dev/null
+++ b/3433/CH10/EX10.5/Ex10_5.sce
@@ -0,0 +1,43 @@
+clear;
+clc;
+funcprot(0);
+
+//given data
+Z = 3;//number of blades
+D = 30;//rotor diameter in m
+J = 5.0;//tip-speed ratio
+l = 1.0;//blade chord in m
+r_R = 0.9;//ratio
+beta = 2;//pitch angle in deg
+
+//Calculations
+//iterating to get values of induction factors
+a = 0.0001;//inital guess
+a_ = 0.0001;//inital guess
+a_new = 0.0002;//inital guess
+i = 0;
+while (a_~=a_new)
+   phi = (180/%pi)*atan((1/(r_R*J))*((1-a)/(1-a_)));
+   alpha = phi-beta;
+   CL = 0.1*alpha;
+   lamda = (Z*l*CL)/(8*%pi*0.5*r_R*D);
+   a = 1/(1+(1/lamda)*sin(phi*%pi/180)*tan(phi*%pi/180));
+   a_new = 1/((1/lamda)*cos(phi*%pi/180) -1);
+   if a_ < a_new
+       a_ = a_ + 0.0001;
+   elseif a_ > a_new
+       a_ = a_ - 0.0001;
+   end    
+   if (abs((a_-a_new)/a_new) < 0.1) then
+       break;
+   end             
+   i = i+1;
+end
+
+//Results
+printf('Axial induction factor, a = %.4f',a);
+printf('\n Tangential induction factor = %.5f',a_new);
+printf('\n phi = %.3f deg.',phi);
+printf('\n Lift coefficient = %.3f.',CL);
+
+//The answers given in textbook are wrong
diff --git a/3433/CH10/EX10.6/Ex10_6.sce b/3433/CH10/EX10.6/Ex10_6.sce
new file mode 100644
index 000000000..5362eec6e
--- /dev/null
+++ b/3433/CH10/EX10.6/Ex10_6.sce
@@ -0,0 +1,50 @@
+clear;

+clc;

+funcprot(0);

+

+//given data

+D = 30;//tip diameter in m

+CL = 0.8;//lift coefficient

+J = 5.0;

+l = 1.0;//chord length in m

+Z = 3;//number of blades

+r_R = [0.2 0.3 0.4 0.6 0.8 0.9 0.95 1.0];

+n = 8;

+//Calculations

+//iterating to get values of induction factors

+a = 0.1;//inital guess

+anew = 0;

+a_ = 0.006;//inital guess

+a_new = 0.0;//inital guess

+for i = 1:n

+    while (a_~=a_new)

+        lamda = (Z*l*CL)/(8*%pi*0.5*r_R(i)*D);

+        phi = (180/%pi)*atan((1/(r_R(i)*J))*((1-a)/(1-a_)));

+        a = 1/(1+(1/lamda)*sin(phi*%pi/180)*tan(phi*%pi/180));

+        a_new = 1/((1/lamda)*cos(phi*%pi/180) -1);

+        alpha = CL/0.1;

+        beta = phi-alpha;

+        if a_ < a_new

+            a_ = a_ + 0.0001;

+        elseif a_ > a_new

+            a_ = a_ - 0.0001;      

+        end    

+        if (abs((a_-a_new)/a_new) < 0.01) then

+            break;

+        end             

+    end

+    p(i) = phi;b(i) = beta;a1(i) = a;a2(i) = a_new;

+end

+

+//Results

+printf('Summary of results of iterations (N.B. CL = 0.8 along the span)');

+printf('\n -----------------------------------------------------------------------------------');

+printf('\n r/R      %.1f      %.1f       %.1f       %.1f      %.1f      %.1f      %.2f        %.1f  ',r_R(1),r_R(2),r_R(3),r_R(4),r_R(5),r_R(6),r_R(7),r_R(8));

+printf('\n -----------------------------------------------------------------------------------');

+printf('\n phi    %.2f     %.2f     %.2f     %.2f    %.2f    %.2f     %.2f       %.3f',p(1),p(2),p(3),p(4),p(5),p(6),p(7),p(8));

+printf('\n beta   %.2f     %.2f     %.2f     %.2f     %.2f     %.2f      %.2f       %.2f',b(1),b(2),b(3),b(4),b(5),b(6),b(7),b(8));

+printf('\n a      %.4f   %.5f   %.5f   %.4f   %.4f   %.4f     %.4f     %.4f',a1(1),a1(2),a1(3),a1(4),a1(5),a1(6),a1(7),a1(8));

+printf('\n a`     %.5f   %.5f   %.5f   %.5f   %.5f   %.5f   %.5f   %.5f',a2(1),a2(2),a2(3),a2(4),a2(5),a2(6),a2(7),a2(8));

+printf('\n -----------------------------------------------------------------------------------');

+

+//there are some errors in the answers given in textbook

diff --git a/3433/CH10/EX10.7/Ex10_7.sce b/3433/CH10/EX10.7/Ex10_7.sce
new file mode 100644
index 000000000..7942aaeef
--- /dev/null
+++ b/3433/CH10/EX10.7/Ex10_7.sce
@@ -0,0 +1,33 @@
+clear;

+clc;

+funcprot(0);

+

+//given data

+//data from Exampla 10.5

+Z = 3;//number of blades

+D = 30;//rotor diameter in m

+J = 5.0;//tip-speed ratio

+l = 1.0;//blade chord in m

+beta = 2;//pitch angle in deg

+omega = 2.5;//in rad/s

+

+rho = 1.2;//density in kg/m^3

+cx1 = 7.5;//in m/s

+sum_var1 = 6.9682;//from Table 10.3

+sum_var2 = 47.509*10^-3;//from Table 10.4

+

+//Calculations

+X = sum_var1*0.5*rho*Z*l*0.5*D*cx1^2;

+tau = sum_var2*0.5*rho*Z*l*(omega^2)*(0.5*D)^4;

+P = tau*omega;

+A2 = 0.25*%pi*D^2;

+P0 = 0.5*rho*A2*cx1^3;

+Cp = P/P0;

+zeta = (27/16)*Cp;

+

+//Results

+printf('The total axial force = %d N.',X);

+printf('\n The torque = %.3f *10^3 Nm.',tau/1000);

+printf('\n The power developed = %.3f kW.',P/1000);

+printf('\n The power coefficient = %.3f',Cp);

+printf('\n The relative power coefficient = %.3f',zeta);

diff --git a/3433/CH10/EX10.8/Ex10_8.sce b/3433/CH10/EX10.8/Ex10_8.sce
new file mode 100644
index 000000000..13faeb679
--- /dev/null
+++ b/3433/CH10/EX10.8/Ex10_8.sce
@@ -0,0 +1,33 @@
+clear;

+clc;

+funcprot(0);

+

+//given data

+X = 10583;//in N

+D = 30;//rotor diameter in m

+Cx = X/23856;

+rho = 1.2;//density in kg/m^3

+cx1 = 7.5;//in m/s

+

+//sloving quadratic eqaution

+a = 0;//inital guess

+res = 1;

+i = 0;

+while (res~=0)

+    res = a*(1-a) - Cx/4;

+    if (res>0) then

+        a = a-0.001;

+    elseif (res<0)

+        a = a+0.001;

+    end

+    if abs(res)<0.0001

+        break;

+    end    

+end

+A2 = 0.25*%pi*D^2

+P = 2*rho*A2*(cx1^3)*a*(1-a)^2;

+

+//Results

+printf('P = %.3f kW.',P/1000);

+

+//there is small error in the answer given in textbook

diff --git a/3433/CH10/EX10.9/Ex10_9.sce b/3433/CH10/EX10.9/Ex10_9.sce
new file mode 100644
index 000000000..f6a4407de
--- /dev/null
+++ b/3433/CH10/EX10.9/Ex10_9.sce
@@ -0,0 +1,74 @@
+clear;

+clc;

+funcprot(0);

+

+//given data

+//data from Exampla 10.5

+Z = 3;//number of blades

+D = 30;//rotor diameter in m

+J = 5.0;//tip-speed ratio

+l = 1.0;//blade chord in m

+beta = 1.59;//pitch angle in deg

+omega = 2.5;//in rad/s

+rho = 1.2;//density in kg/m^3

+cx1 = 7.5;//in m/s

+c1 = 1518.8;//from Ex 10.6

+c2 = 0.5695*10^6;

+P0 = 178.96;//Power developed in kW from Ex 10.7

+X1 = 10582;//Total axial force in N from Ex 10.7

+Cp1 = 0.378;//Power coefficient from Ex 10.7

+zeta1 = 0.638;//rekative power coefficient from Ex 10.7

+

+//Calculations

+r_R = 0.25:0.1:0.95;

+b = [28.4;19.49;13.80;9.90;7.017;4.900;3.00;1.59];

+//b = [27.2985;17.8137;11.8231;7.8176;4.9972;3.0511;1.6476;1.59];

+for j = 1:8

+    i = 1;

+    atemp = 0; a_temp = 0;

+    while i>0,        i = i+1;

+        f = (2/%pi)*acos(exp(-0.5*Z*(1-r_R(j))*(1+J^2)^0.5));

+        phi = (180/%pi)*atan((1/(J*r_R(j)))*((1-atemp)/(1+a_temp)));

+        CL = (phi-b(j))/10;

+        lamda = f/(63.32/CL);

+        anew = (lamda*cos(phi*%pi/180)/(lamda*cos(phi*%pi/180)+f*(sin(phi*%pi/180))^2));

+        if atemp<anew then

+            atemp = atemp+0.0001;

+        elseif atemp>anew

+            atemp = atemp-0.0001;

+        end

+        if (abs((atemp-anew)/anew) < 0.001) then

+            break;

+        end 

+    end

+    F(j) = f;

+    ph(j) = phi;

+    cl(j) = CL;

+    a(j) = anew; 

+    Var1(j) = ((1-anew)/sin(phi*%pi/180))^2 *cos(phi*%pi/180)*CL*0.1;

+//    a_(j) = lamda/(F*cos(phi*%pi/180)-lamda); 

+//printf('r_R = %.2f, F = %.4f, a = %.4f, phi = %.4f\n',r_R(j),F(j),a(j),ph(j));

+end

+

+for k = 1:8

+    lam(k) = F(k)*cl(k)/63.32;

+    a_new(k) = lam(k)/(F(k)*cos(ph(k)*%pi/180)-lam(k)); 

+    Var2(k) = ((1+a_new(k))/cos(phi*%pi/180))^2 *(r_R(k))^3 *cl(k)*sin(ph(k)*%pi/180)*0.1;

+end

+X = c1*sum(Var1(1:8));

+sum_Var2 = 40.707*10^-3;

+tau = c2*sum(Var2(1:8));

+P = tau*omega;

+Cp = P/(P0*1000);

+zeta = (26/17)*Cp;

+

+//Results

+printf('               Summary of Results:');

+printf('\n ---------------------------------------------------------------------------------------------------');

+printf('\n                             Axial force, kN        Power, kW             Cp               zeta');

+printf('\n ---------------------------------------------------------------------------------------------------');

+printf('\n Without tip correction           %.3f              %.2f              %.3f             %.3f',X1/1000,P0*Cp1,Cp1,zeta1);

+printf('\n With tip correction              %.3f               %.2f              %.3f             %.3f',X/1000,P/1000,Cp,zeta);

+printf('\n ---------------------------------------------------------------------------------------------------');

+

+//There are errors in the answers given in textbook