//CHAPTER 11 ILLUSRTATION 11 PAGE NO 297 //TITLE:VIBRATIONS //FIGURE 11.19 clc clear //=========================================================================================== //INPUT DATA PI=3.147 g=9.81// ACCELERATION DUE TO GRAVITY IN N /m^2 E=210*10^9// YOUNGS MODUKUS OF SHAFT MATERIAL IN Pascals D=.18// DIAMETER OF SHAFT IN m L=2.5// LENGTH OF SHAFT IN m M1=25// MASS ACTING AT E IN Kg M2=50// MASS ACTING AT D IN Kg M3=20// MASS ACTING AT C IN Kg W1=M1*g W2=M2*g W3=M3*g L1=.6// LENGTH FROM A TO E IN m L2=1.5// LENGTH FROM A TO D IN m L3=2// LENGTH FROM A TO C IN m w=1962// SELF WEIGHT OF SHAFT IN N //========================================================================================== I=PI*D^4/64// MOMENT OF INERTIA OF SHAFT IN m^4 DELTA1=W1*L1^2*(L-L1)^2/(3*E*I*L)// STATIC DEFLECTION DUE TO W1 DELTA2=W2*L2^2*(L-L2)^2/(3*E*I*L)// STATIC DEFLECTION DUE TO W2 DELTA3=W3*L3^2*(L-L3)^2/(3*E*I*L)// STATIC DEFLECTION DUE TO W3 DELTA4=5*w*L^4/(384*E*I)// STATIC DEFLECTION DUE TO w Fn=.4985/(DELTA1+DELTA2+DELTA3+DELTA4/1.27)^.5 Nc=Fn*60// CRITICAL SPEED OF SHAFT IN rpm //======================================================================================== printf('CRITICAL SPEED OF SHAFT = %.3f rpm',Nc)