//CHAPTER 7 ILLUSRTATION 9 PAGE NO 204 //TITLE:GOVERNORS //FIGURE 7.3(C) clc clear //=========================================================================================== //INPUT DATA g=9.81// ACCELERATION DUE TO GRAVITY PI=3.147 r=.14// DISTANCE BETWEEN THE CENTRE OF PIVOT OF BELL CRANK LEVER AND AXIS OF GOVERNOR SPINDLE IN m r2=.11// INITIAL RADIUS OF ROTATION IN m a=.12// LENGTH OF VERTICAL ARM OF BELL CRANK LEVER IN m b=.10// LENGTH OF HORIZONTAL ARM OF BELL CRANK LEVER IN m h=.05// SLEEVE LIFT IN m N2=240// INITIAL SPEED IN rpm F=30// FRICTIONAL FORCE ACTING IN N m=5// MASS OF EACH BALL IN Kg //========================================== r1=r2+a/b*h// MAX RADIUS OF ROTATION IN m N1=41*N2/39// MAX SPEED OF ROTATION IN rpm N=(N1+N2)/2// MEAN SPEED IN rpm Fc1=m*(2*PI*N1/60)^2*r1// CENTRIFUGAL FORCE ACTING AT MAX SPEED OF ROTATION IN N Fc2=m*(2*PI*N2/60)^2*r2// CENTRIFUGAL FORCE ACTING AT MIN SPEED OF ROTATION IN N c1=r1-r// FROM FIGURE 7.3(C) IN m a1=(a^2-c1^2)^.5// FROM FIGURE 7.3(C) IN m b1=(b^2-(h/2)^2)^.5// FROM FIGURE 7.3(C) IN m c2=r-r2// FROM FIGURE 7.3(C) IN m a2=a1// FROM FIGURE 7.3(C) IN m b2=b1// FROM FIGURE 7.3(C) IN m S1=2*((Fc1*a1)-(m*g*c1))/b1// SPRING FORCE EXERTED ON THE SLEEVE AT MAXIMUM SPEED IN NEWTONS S2=2*((Fc2*a2)-(m*g*c2))/b2// SPRING FORCE EXERTED ON THE SLEEVE AT MAXIMUM SPEED IN NEWTONS S=(S1-S2)/h// STIFFNESS OF THE SPRING IN N/m Is=S2/S// INITIAL COMPRESSION OF SPRING IN m P=S2+(h/2*S)// SPRING FORCE OF MID PORTION IN N n1=N*((P+F)/P)^.5// SPEED,WHEN THE SLEEVE BEGINS TO MOVE UPWARDS FROM MID POSITION IN rpm n2=N*((P-F)/P)^.5// SPEED,WHEN THE SLEEVE BEGINS TO MOVE DOWNWARDS FROM MID POSITION IN rpm A=n1-n2// ALTERATION IN SPEED IN rpm printf('INTIAL COMPRESSION OF SPRING= %.3f cm\n ALTERATION IN SPEED = %.3f rpm',Is*100,A)