diff options
Diffstat (limited to '3774/CH3')
-rw-r--r-- | 3774/CH3/EX3.1/Ex3_1.sce | 23 | ||||
-rw-r--r-- | 3774/CH3/EX3.10/Ex3_10.sce | 27 | ||||
-rw-r--r-- | 3774/CH3/EX3.11/Ex3_11.sce | 26 | ||||
-rw-r--r-- | 3774/CH3/EX3.12/Ex3_12.sce | 25 | ||||
-rw-r--r-- | 3774/CH3/EX3.13/Ex3_13.sce | 48 | ||||
-rw-r--r-- | 3774/CH3/EX3.2/Ex3_2.sce | 25 | ||||
-rw-r--r-- | 3774/CH3/EX3.3/Ex3_3.sce | 23 | ||||
-rw-r--r-- | 3774/CH3/EX3.4/Ex3_4.sce | 45 | ||||
-rw-r--r-- | 3774/CH3/EX3.5/Ex3_5.sce | 28 | ||||
-rw-r--r-- | 3774/CH3/EX3.6/Ex3_6.sce | 25 | ||||
-rw-r--r-- | 3774/CH3/EX3.8/Ex3_8.sce | 22 |
11 files changed, 317 insertions, 0 deletions
diff --git a/3774/CH3/EX3.1/Ex3_1.sce b/3774/CH3/EX3.1/Ex3_1.sce new file mode 100644 index 000000000..357bcaf6b --- /dev/null +++ b/3774/CH3/EX3.1/Ex3_1.sce @@ -0,0 +1,23 @@ +// exa 3.1 Pg 62 + +clc;clear;close; + +// Given Data +P=30;// kN +Sut=350;// MPa +n=2.5;// factor of safety + +sigma_w=Sut/n;// MPa (Working stress for the link) + +t=poly(0,'t');// thickness of link +A=2.5*t**2;// mm.sq. +I=t*(2.5*t)**3/12;// mm^4 (Moment of Inertia about N-A) +sigma_d=P/A;// N/mm.sq. +e=10+1.25*t;//mm +M=P*10**3*e;// N.mm +sigma_t=M*1.25*t/I;// N/mm.sq. +//maximum tensile stress at the top fibres = sigma_d+sigma_t=sigma_w ...eqn(1) +expr=sigma_d+sigma_t-sigma_w ;// expression of polynomial from above eqn. +t=roots(numer(expr));// solving the equation (as denominator will me be multiplied by zero on R.H.S) +t=t(1);// mm // discarding -ve roots +printf('dimension of cross section of link, t=%.f mm. Adopt t=21 mm. ',t) diff --git a/3774/CH3/EX3.10/Ex3_10.sce b/3774/CH3/EX3.10/Ex3_10.sce new file mode 100644 index 000000000..a9d5db7fa --- /dev/null +++ b/3774/CH3/EX3.10/Ex3_10.sce @@ -0,0 +1,27 @@ +// exa 3.10 Pg 71 + +clc;clear;close; + +// Given Data +d=4;// cm +M=15000;// N.cm +Syt=20000;// N/cm.sq. + +printf('\n (i) Maximum Principal Stress Theory-') +z=%pi*d**3/32;// cm.cube. +sigma_b=M/z;// N/cm.sq. +T=poly(0,'T') +tau=16*T/(%pi*d**3);// N/cm.sq. +//sigma1=(1/2)*(sigma_b+sqrt(sigma_b**2+4*tau**2)) // Maximum principal stress +//sigma1=(sigma_b/2+sqrt(sigma_b**2/4+tau**2)) // on solving +//tau=sqrt((sigma1-sigma_b/2)**2-sigma_b**2/4) +sigma1=Syt;// N/cm.sq. +T=sqrt((sigma1-sigma_b/2)**2-sigma_b**2/4)*(%pi*d**3)/16;// N.cm. +printf('\n Maximum value of torque, T = %.f N.cm.',T) + +printf('\n (ii) Maximum Shear Stress Theory') +tau_d=0.5*Syt;// N.cm. +//Te=sqrt(M**2+T**2)=(%pi/16)*d**3*tau_d +T=sqrt(((%pi/16)*d**3*tau_d)**2-M**2);// N.cm. +printf('\n Maximum value of torque, T = %.f N.cm.',T) +// Answer in the textbook is not accurate. diff --git a/3774/CH3/EX3.11/Ex3_11.sce b/3774/CH3/EX3.11/Ex3_11.sce new file mode 100644 index 000000000..529217bd8 --- /dev/null +++ b/3774/CH3/EX3.11/Ex3_11.sce @@ -0,0 +1,26 @@ +// exa 3.11 Pg 72 + +clc;clear;close; + +// Given Data +N=200;// rpm +P=25;// kW +tau_d=42;// MPa +W=900;// N +L=3;// m +Syt=56;// MPa +Syc=56;// MPa +sigma_d=56;// MPa + +T=P*60*10**3/(2*%pi*N);// N.m +M=W*L/4;// N.m +Te=sqrt(M**2+T**2);// N.m +// Te=(%pi/16)*d**3*tau_d +d=(Te*10**3/((%pi/16)*tau_d))**(1/3);// mm +printf('\n shaft diameter(using equivalent torque)-\n d=%.f mm.',d) + +Me=(1/2)*(M+sqrt(M**2+T**2));//N.m +// Me=(%pi/32)*d**3*sigma_d +d=(Me*10**3/((%pi/32)*sigma_d))**(1/3);// mm +printf('\n shaft diameter(using equivalent bending moment)-\n d=%.f mm.',d) +printf('\n adopt d=57 mm.') diff --git a/3774/CH3/EX3.12/Ex3_12.sce b/3774/CH3/EX3.12/Ex3_12.sce new file mode 100644 index 000000000..7b94e8c01 --- /dev/null +++ b/3774/CH3/EX3.12/Ex3_12.sce @@ -0,0 +1,25 @@ +// exa 3.12 Pg 72 + +clc;clear;close; + +// Given Data +sigma_w=60;// MPa +F=10;// kN +alfa=30;// degree + +FH=F*sind(alfa);// kN +FV=F*cosd(alfa);// kN +t=poly(0,'t');// mm +A=t*t;// mm.sq. +sigma_d=FV*10**3/A +M=FV*10**3*120+FH*10**3*150;// N.mm +I=t*(2*t)**3/12;// mm^4 +sigma_t=M*t/I;// N/mm.sq. +// Tensile stress at A=sigma_d+sigma_t=sigma_w ...eqn(1) +expr = sigma_d+sigma_t-sigma_w;// polynomial from above eqn. +t=roots(numer(expr));// roots of the polynomial +t=t(1);// mm // discarding -ve roots +printf('\n value of t = %.1f mm',t) +A=2*t**2;// mm.sq. +printf('\n Area of cross-section of Hanger, A = %.f mm.sq.',A) +// Note-Answer in the textbook is slighly wrong and cross section not calculated. diff --git a/3774/CH3/EX3.13/Ex3_13.sce b/3774/CH3/EX3.13/Ex3_13.sce new file mode 100644 index 000000000..bbbecc0e8 --- /dev/null +++ b/3774/CH3/EX3.13/Ex3_13.sce @@ -0,0 +1,48 @@ +// exa 3.13 Pg 74 + +clc;clear;close; + +// Given Data +P=15;// kW +n1=200;// rpm +l=600;// mm +z2=18;// no. of teeth +m2=5;// mm +alfa2=14.5;// degree +l2=120;// mm +z1=72;// no. of teeth +m1=5;// mm +alfa1=14.5;// degree +l1=150;// mm +sigma_d=80;// MPa + +d1=m1*z1;// mm +v1=%pi*d1*n1/(60*10**3);// m/s +Ft1=10**3*P/v1;// N (outwards) +Fr1=Ft1*tand(alfa1);// N (Downwards) +d2=m2*z2;// mm +v2=%pi*d2*n1/(60*10**3);// m/s +Ft2=10**3*P/v2;// N (outwards) +Fr2=Ft2*tand(alfa2);// N (Upwards) + +// RAV*600=Fr1*450+Fr2*120 (Taking moments about bearing B) +RAV=(Fr1*450+Fr2*120)/600;// N (Downwards) +RBV=(Fr1-Fr2-RAV);// N (upwards) +MCV=RAV*l1;// N.mm +MBV=Fr2*l2;// N.mm + +// RAH*600=-Ft1*450+Ft2*120 (Taking moments about bearing B) +RAH=(-Ft1*450+Ft2*120)/600;// N (Outwards) +RBH=Ft1+Ft2+RAH;// N (inwards) +MCH=RAH*l1;// N.mm +MBH=Ft2*l2;// N.mm + +// Resultant Bending Moments +MC=sqrt(MCV**2+MCH**2);// N.mm +MB=sqrt(MBV**2+MBH**2);// N.mm +Mmax=max(MC,MB);// N.mm +T=10**3*P/(2*%pi*n1);// N.m +Me=(1/2)*(Mmax+sqrt(Mmax**2+T**2));// N.mm +// Me=(%pi/32)*d**3*sigma_d +d=(Me/((%pi/32)*sigma_d))**(1/3) +printf('\n shaft diameter is : %.f mm',d) diff --git a/3774/CH3/EX3.2/Ex3_2.sce b/3774/CH3/EX3.2/Ex3_2.sce new file mode 100644 index 000000000..5414dc4be --- /dev/null +++ b/3774/CH3/EX3.2/Ex3_2.sce @@ -0,0 +1,25 @@ +// exa 3.2 Pg 63 + +clc;clear;close; + +// Given Data +P=6;// kN +alfa=30;// degree +Sut=250;// MPa +n=2.5;// factor of safety + +sigma_w=Sut/n;// MPa (Working stress for the link) +PH=P*10**3*cosd(alfa);// kN +PV=P*10**3*sind(alfa);// kN + +t=poly(0,'t');// thickness of link +A=2*t*t;// mm.sq. +sigma_d=PH/A;// N/mm.sq. +M=PH*100+PV*250;// N.mm +I=t*(2*t)**3/12;// mm^4 (Moment of Inertia) +sigma_t=M*t/I;// N/mm.sq. +//maximum tensile stress at the top fibres = sigma_d+sigma_t=sigma_w ...eqn(1) +expr=sigma_d+sigma_t-sigma_w ;// expression of polynomial from above eqn. +t=roots(numer(expr));// solving the equation (as denominator will me be multiplied by zero on R.H.S) +t=t(1);// mm // discarding -ve roots +printf('dimension of cross section of link, t=%.f mm.',t) diff --git a/3774/CH3/EX3.3/Ex3_3.sce b/3774/CH3/EX3.3/Ex3_3.sce new file mode 100644 index 000000000..6a1fcf9f1 --- /dev/null +++ b/3774/CH3/EX3.3/Ex3_3.sce @@ -0,0 +1,23 @@ +// exa 3.3 Pg 64 + +clc;clear;close; + +// Given Data +P=20;// kN +Sut=300;// MPa +n=3;// factor of safety + +sigma_w=Sut/n;// MPa (Working stress for the link) + +t=poly(0,'t');// thickness of link +A=4*t*t;// mm.sq. +sigma_d=P*10**3/A;// N/mm.sq. +e=6*t;//mm +M=P*10**3*e;// N.mm +z=t*(4*t)**2/6;// mm^3 (section modulus at x1-x2) +sigma_b=M/z;// N/mm.sq. +//maximum tensile stress at x1 = sigma_d+sigma_b=sigma_w ...eqn(1) +expr=sigma_d+sigma_b-sigma_w ;// expression of polynomial from above eqn. +t=roots(numer(expr));// solving the equation (as denominator will me be multiplied by zero on R.H.S) +t=t(2);// mm // discarding -ve roots +printf('dimension of cross section of link, t=%.2f mm. Use 23 mm.',t) diff --git a/3774/CH3/EX3.4/Ex3_4.sce b/3774/CH3/EX3.4/Ex3_4.sce new file mode 100644 index 000000000..b8f3b6496 --- /dev/null +++ b/3774/CH3/EX3.4/Ex3_4.sce @@ -0,0 +1,45 @@ +// exa 3.4 Pg 65 + +clc;clear;close; + +// Given Data +P=15;// kN +sigma_t=20;// MPa +sigma_c=60;// MPa +n=3;// factor of safety + +a=poly(0,'a');// from the diagram. +// Area of cross section +A1=2*a*a;// mm.sq. +A2=2*a*a/2;// mm.sq. +A=A1+A2;// mm.sq. + +// Location of neutral axis +//3*a**2*y_bar=2*a**2*a/2+a**2*(a+a/2) +y_bar=(2*a**2*a/2+a**2*(a+a/2))/(3*a**2);// mm + +// Moment of Inertia about neutral axis N-A +I=2*a*a**3/12+2*a**2*(y_bar-0.5*a)**2+2*((a/2)*(a**3/12)+(a**2/2)*(1.5*a-y_bar)**2);// mm^4 +yt=y_bar;//mm +yc=2*a-y_bar;// mm +e=y_bar-0.5*a;//mm +M=P*10**3*e;// N.mm +sigma_d=P*10**3/A;// N/mm.sq. +sigma_t1=M*yt/I;//N/mm.sq. +sigma_c1=M*yc/I;//N/mm.sq. +sigma_r_t=sigma_d+sigma_t1;// N/mm.sq. (sigma_r_t=resultant tensile stress at AB=sigma_d+sigma_t) +sigma_r_c=sigma_c1-sigma_d;// N/mm.sq. (sigma_r_t=resultant tensile stress at AB=sigma_d+sigma_t) + +//equating resulting tensile stress with given value sigma_t-sigma_r_t=0...eqn(1) +expr1=sigma_t-sigma_r_t;// expression of polynomial from above eqn. +a1=roots(numer(expr1));// solving the equation (as denominator will me be multiplied by zero on R.H.S) +a1=a1(2);// mm // discasrding -ve roots +printf('Equating resultant tensile stress gives, a = %.2f mm',a1) + +//equating resulting compressive stress with given value sigma_c-sigma_c_t=0...eqn(1) +expr2=sigma_c-sigma_r_c;// expression of polynomial from above eqn. +a2=roots(numer(expr2));// solving the equation (as denominator will me be multiplied by zero on R.H.S) +a2=a2(2);// mm // discarding -ve roots +printf('\n Equating resultant compressive stress gives, a = %.2f mm',a2) +a=ceil(a1);//mm +printf('\n dimension of cross section of link, a=%.2f mm. adopt a=%.f mm.',a1,a) diff --git a/3774/CH3/EX3.5/Ex3_5.sce b/3774/CH3/EX3.5/Ex3_5.sce new file mode 100644 index 000000000..a09bdbdd0 --- /dev/null +++ b/3774/CH3/EX3.5/Ex3_5.sce @@ -0,0 +1,28 @@ +// exa 3.5 Pg 67 + +clc;clear;close; + +// Given Data +Syt=760;// MPa +M=15;// kN.m +T=25;//kN.m +n=2.5;// factor of safety +E=200;// GPa +v=0.25;// Poisson's ratio + +sigma_d=Syt/n;// MPa +// let d is diameter of the shaft +sigma_b_into_d_cube=32*M*10**6/%pi;// N/mm.sq. (where sigma_b_into_d_cube = sigma_d*d**3) +tau_into_d_cube=16*T*10**6/%pi//d**3;// N/mm.sq. (where tau_into_d_cube = tau*d**3) +sigma1_into_d_cube=sigma_b_into_d_cube/2+1/2*sqrt(sigma_b_into_d_cube**2+4*tau_into_d_cube**2) ; // (where sigma1_into_d_cube=sigma1*d**3) +sigma2_into_d_cube=sigma_b_into_d_cube/2-1/2*sqrt(sigma_b_into_d_cube**2+4*tau_into_d_cube**2); // (where sigma2_into_d_cube=sigma2*d**3) +printf('\n (i) Maximum shear stress theory') +tau_max_into_d_cube=(sigma1_into_d_cube-sigma2_into_d_cube)/2; //(where tau_max_into_d_cube = tau_max*d**3) +d=(tau_max_into_d_cube/(sigma_d/2))**(1/3);//mm +printf('diameter of shaft, d=%.1f mm or %.f mm',d,ceil(d)) + +printf('\n (ii) Maximum strain energy theory') +//sigma1**2+sigma2**2-2*v*sigma1*sigma2=sigma_d**2 +d=((sigma1_into_d_cube**2+sigma2_into_d_cube**2-2*v*sigma1_into_d_cube*sigma2_into_d_cube)/sigma_d**2)**(1/6) +printf('diameter of shaft, d=%.1f mm',d) +printf('\n Adopt d=100mm') diff --git a/3774/CH3/EX3.6/Ex3_6.sce b/3774/CH3/EX3.6/Ex3_6.sce new file mode 100644 index 000000000..fc7afb40c --- /dev/null +++ b/3774/CH3/EX3.6/Ex3_6.sce @@ -0,0 +1,25 @@ +// exa 3.6 Pg 69 + +clc;clear;close; + +// Given Data +N=200;// rpm +P=200;// kW +tau_d=42;// Mpa +W=900;// N +L=3;// m +sigma_t=56;// MPa +sigma_c=56;// MPa + +T=P*60*10**3/(2*%pi*N);// N.m +M=W*L/4;// N.m +Te=sqrt(M**2+T**2);// N.m +//Te=(%pi/16)*d**3*tau_d +d=(Te/((%pi/16)*tau_d)*1000)**(1/3);// mm +printf('\n Using equivalent torque equation,\n shaft diameter d = %.f mm',d) + +Me=(1/2)*(M+sqrt(M**2+T**2));// N.m +//Me=(%pi/32)*d**3*sigma_d +d=(Me/((%pi/32)*sigma_c)*10**3)**(1/3);//mm +printf('\n Using equivalent bending moment equation,\n shaft diameter d = %.2f mm or %.f mm',d, ceil(d)) +printf('\n Adopt d=105 mm.') diff --git a/3774/CH3/EX3.8/Ex3_8.sce b/3774/CH3/EX3.8/Ex3_8.sce new file mode 100644 index 000000000..1003c0c77 --- /dev/null +++ b/3774/CH3/EX3.8/Ex3_8.sce @@ -0,0 +1,22 @@ +// exa 3.8 Pg 70 + +clc;clear;close; + +// Given Data +M=15;// N.m +P=5;// kW +N=500;// rpm +tau_d=40;// Mpa +sigma_d=58;// MPa + +T=P*60*10**3/(2*%pi*N);// N.m +Te=sqrt(M**2+T**2);// N.m +//Te=(%pi/16)*d**3*tau_d +d=(Te/((%pi/16)*tau_d)*1000)**(1/3);// mm +printf('\n Using equivalent torque equation,\n shaft diameter d = %.f mm',d) + +Me=(1/2)*(M+sqrt(M**2+T**2));// N.m +//Me=(%pi/32)*d**3*sigma_d +d=(Me/((%pi/32)*sigma_d)*10**3)**(1/3);//mm +printf('\n Using equivalent bending moment equation,\n shaft diameter d = %.2f mm or %.f mm',d, ceil(d)) +printf('\n Adopt d=23 mm.') |