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//CHAPTER 5 ILLUSRTATION 8 PAGE NO 166
//TITLE:Inertia Force Analysis in Machines
//figure 5.4
clc
clear
pi=3.141
D=.25// diameter of vertical cylinder of diesel engine in m
L=.40// stroke length in m
r=L/2
n=4
N=300// speed of the engine in rpm
teeta=60// angle of inclination of crank in degrees
mR=200// mass of reciprocating parts in kg
g=9.81// acceleration due to gravity
l=.8// length of connecting rod in m
c=14// compression ratio=v1/v2
p1=.1*10^6// suction pressure in n/m^2
i=1.35// index of the law of expansion and compression
//==============================================================
Vs=pi/4*D^2*L// swept volume in m^3
w=2*pi*N/60// angular speed in rad/s
Vc=Vs/(c-1)
V3=Vc+Vs/10// volume at the end of injection of fuel in m^3
p2=p1*c^i// final pressure in N/m^2
p3=p2// from figure
x=r*((1-cosd(teeta)+(sind(teeta))^2/(2*n)))// the displacement of the piston when the crank makes an angle 60 degrees with T.D.C
Va=Vc+pi*D^2*x/4
pa=p3*(V3/Va)^i
p=pa-p1// difference of pressues on 2 sides of piston in N/m^2
Fl=p*pi*D^2/4// net load on piston in N
Fi=mR*w^2*r*(cosd(teeta)+cosd(2*teeta)/(n))// inertia force due to reciprocating parts in N
Fp=Fl-Fi+mR*g// piston effort in N
phi=asind(sind(teeta)/n)// angle of inclination of the connecting rod to the line of stroke in degrees
T=Fp*sind(teeta+phi)/cosd(phi)*r// torque exerted on crank shaft in N-m
printf('Effective turning moment on the crank shaft= %.3f N-m',T)
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