diff options
Diffstat (limited to '2063/CH7')
28 files changed, 645 insertions, 0 deletions
diff --git a/2063/CH7/EX7.1/7_1.sce b/2063/CH7/EX7.1/7_1.sce new file mode 100755 index 000000000..3fc4eec73 --- /dev/null +++ b/2063/CH7/EX7.1/7_1.sce @@ -0,0 +1,15 @@ +clc
+clear
+//Input data
+N=1500;//Engine speed in rpm
+p=110;//Load on brakes in kg
+L=900;//Length of brake arm in mm
+g=9.81;//Gravitational force in N/m^2
+pi=3.14;//Mathematical constant
+
+//Calculations
+T=((p*g)*(L/1000));//Braking torque in Nm
+P=((T/1000)*((2*3.14*N)/60));//Power available at the brakes of the engine in kW
+
+//Output
+printf('(a) Brake torque is %3.1f Nm \n (b)Power available at the brakes of the engine is %3.2f kW',T,P)
diff --git a/2063/CH7/EX7.10/7_10.sce b/2063/CH7/EX7.10/7_10.sce new file mode 100755 index 000000000..1c2088003 --- /dev/null +++ b/2063/CH7/EX7.10/7_10.sce @@ -0,0 +1,17 @@ +clc
+clear
+//Input data
+d=6;//Diameter of the bore in cm
+l=9;//Length of the stroke in cm
+m=0.00025;//Mass of charge admitted in each suction stroke
+R=29.27;//Gas constant Kgfm/kg K
+p=1;//Normal pressure in kgf/cm^2
+T=273;//Temperature in K
+
+//Calculations
+V=(m*R*T)*10^6/(p*10^4);//Volume of charge admitted in each cycle in m^3
+Vs=(3.14*d^2*l)/4;//Swept volume of the cylinder
+nv=(V/Vs)*100;//Volumetric efficiency in percentage
+
+//Output
+printf('The volumetric efficiency is %3.1f percent',nv)
diff --git a/2063/CH7/EX7.11/7_11.sce b/2063/CH7/EX7.11/7_11.sce new file mode 100755 index 000000000..b9677d248 --- /dev/null +++ b/2063/CH7/EX7.11/7_11.sce @@ -0,0 +1,28 @@ +clc
+clear
+//Input data
+d=0.12;//Diameter of the bore in m
+l=0.13;//Length of stroke in m
+N=2500;//Speed of the engine in rpm
+d1=0.06;//Diameter of the orifice in m
+Cd=0.70;//Discharge coefficient of orifice
+hw=33;//Heat causing air flow through orifice in cm of water
+p=760;//Barometric reading in mm of Hg
+T1=298;//Ambient temperature in degree K
+p1=1.013;//Pressure of air at the end of suction in bar
+T2=22;//Temperature of air at the end of suction in degree C
+R=0.287;//Universal gas constant
+n=6;//Number of cylinders in the engine
+n1=1250;//Number of strokes per minute for a four stroke engine operating at 2500 rpm
+
+//Calculations
+V=(3.14*d^2*l)/4;//Swept volume of piston in m^3
+Ao=(3.14*d1^2)/4;//Area of the orifice in m^2
+rho=p1*10^5/((R*T1)*1000);//Density of air at 1.013 bar and 22 degrees C
+Va=840*Cd*Ao*(hw/rho)^(1/2);//Volume of air passing through the orifice in m^3/min
+V1=8.734/n;//Actual volume of air per cylinder in m^3/min
+As=V1/n1;//Air supplied per cycle per cylinder in m^3
+nv=(As/V)*100;//Volumetric efficiency of the engine in percentage
+
+//Output
+printf('The volumetric efficiency of the engine is %3.2f percent',nv)
diff --git a/2063/CH7/EX7.12/7_12.sce b/2063/CH7/EX7.12/7_12.sce new file mode 100755 index 000000000..9ac9a1dc9 --- /dev/null +++ b/2063/CH7/EX7.12/7_12.sce @@ -0,0 +1,24 @@ +clc
+clear
+//Input data
+d=0.15;//Diameter of the piston in m
+l=0.19;//Length of the stroke in m
+V=0.00091;//Clearance volume in m^3
+N=250;//Speed of the engine in rpm
+M=6.5;//Indicated mean effective pressure in bar
+c=6.3;//Gas consumption in m^3/hr
+H=16000;//Calorific value of the has in kJ/m^3
+r1=1.4;//Polytropic index
+
+//Calculations
+Vs=(3.14*d^2*l)/4;//Swept volume in m^3
+Vt=Vs+V;//Total cylinder volume in m^3
+r=Vt/V;//Compression ratio
+na=(1-(1/r^(r1-1)))*100;//Air standard efficiency in percent
+A=(3.14*d^2)/4;//Area of the bore in m
+I=(M*10^5*l*A*N)/(1000*60);//Indicated power in kW
+Hs=(c*H)/(60*60);//Heat supplied per second
+nt=(I/Hs)*100;//Indicated thermal efficiency in percent
+
+//Output
+printf('(a)The air standard efficiency is %3.1f percent\n (b)Indicated power is %3.3f kW\n (c)Indicated thermal efficiency is %3.1f percent',na,I,nt)
diff --git a/2063/CH7/EX7.13/7_13.sce b/2063/CH7/EX7.13/7_13.sce new file mode 100755 index 000000000..572303bdc --- /dev/null +++ b/2063/CH7/EX7.13/7_13.sce @@ -0,0 +1,29 @@ +clc
+clear
+//Input data
+ma=6;//Air supplied per minute by a single jet carburetor in kg/min
+mf=0.44;//Mass flow rate of petrol in kg/min
+s=0.74;//Specific gravity of petrol in kg/m^3
+p1=1;//Initial pressure of air in bar
+T1=300;//Initial temperature of air in K
+Ci=1.35;//Isentropic coefficient of air
+V=90;//Speed of air in the venturi in m/s
+Vc=0.85;//Velocity coefficient of the venturi in m/s
+Cf=0.66;//Coefficient of discharge for the jet
+Cp=1005;//Coefficient of pressure in J/kg K
+n=1.35;//Isentropic coefficient of air
+R=0.281;//Real gas constant in Nm/kg K
+rhof=740;//Density of fuel in mm of Hg
+
+//Calculations
+p2=(1-((V/Vc)^(2)/(2*T1*Cp)))^((n)/(n-1));//Pressure at the venturi in bar
+V1=((R*T1)/(p1*10^5))*1000;//Initial volume in m^3/kg
+V2=V1*((p1/p2)^(0.741));//Final volume in m^3/kg
+A2=((ma*V2)/(V*60))*10^4;//Throat area of venturi in cm^2
+d=((A2*4)/3.14)^(0.5);//Diameter of venturi in cm
+deltaPa=1-p2;//Pressure drop causing air flow in bar
+deltaPf=0.8*deltaPa;//Pressure drop causing fuel flow in bar
+Af=(mf/60)*(10^4)/((Cf)*(2*rhof*deltaPf*10^5)^(1/2));//Area through which fuel flows in cm^2
+df=((Af*(4/3.14))^(1/2))*10;//Diameter of fuel jet in mm
+
+printf('(a)The diameter of the venturi of the venturi if the air speed is 90 m/s is %3.2f cm\n (b)The diameter of the jet if the pressure drop at the jet is 0.8 times the pressure drop at the venturi is %3.4f mm',d,df)
diff --git a/2063/CH7/EX7.14/7_14.sce b/2063/CH7/EX7.14/7_14.sce new file mode 100755 index 000000000..8bbbc9ff8 --- /dev/null +++ b/2063/CH7/EX7.14/7_14.sce @@ -0,0 +1,20 @@ +clc
+clear
+//Input data
+r=14;//The compression ratio of a diesel engine
+Vc=1;//Clearance volume in m^3
+c=0.08;//Fuel supply cut off point
+nr=0.55;//Relative efficiency
+H=10000;//Calorific value of fuel in kcal/kg
+r1=1.4;//Ratio of specific heat of air
+Vs=13;//Stroke volume in m^3
+
+//Calculations
+rho=Vc+(c*Vs);//Cut off ratio
+na=1-(1*(rho^r1-1)/((r^(r1-1)*r1)*(rho-1)));//Air standard efficiency of diesel cycle in percent
+In=(na*nr);//Indicated thermal efficiency in percent
+H1=(4500*60)/(In*427);//Heat in fuel supplied/1HP hr
+W=H1/10^4;//Weight of fuel required/1HP hr
+
+//Output
+printf('The weight of fuel required per 1HP hr is %3.4f kg',W)
diff --git a/2063/CH7/EX7.15/7_15.sce b/2063/CH7/EX7.15/7_15.sce new file mode 100755 index 000000000..5cc6db7ae --- /dev/null +++ b/2063/CH7/EX7.15/7_15.sce @@ -0,0 +1,17 @@ +clc
+clear
+//Input data
+P=120;//Power developed by a six cykinder four stroke diesel engine
+N=2400;//Speed in rpm
+f=0.2;//Brake specific fuel consumption in kg/kWh
+s=0.85;//Specific gravity of fuel
+
+//Calculations
+F=f*P;//Fuel consumed per hour in kg
+F1=F/6;//Fuel consumed per cylinder in kg/h
+n=(N*60)/2;//Number of cycles per hour
+F2=(F1/n)*10^3;//Fuel consumption per cycle in gm
+V=F2/s;//Volume of fuel to be injected per cycle in cc
+
+//Output
+printf('The quantity kof fuel to be injected per cycle per cylinder is %3.4f cc',V)
diff --git a/2063/CH7/EX7.16/7_16.sce b/2063/CH7/EX7.16/7_16.sce new file mode 100755 index 000000000..e23702fa0 --- /dev/null +++ b/2063/CH7/EX7.16/7_16.sce @@ -0,0 +1,22 @@ +clc
+clear
+//Input data
+P=20;//Power developed by a four stroke diesel engine per cylinder in kW
+N=2000;//Operating speed of the diesel engine in rpm
+s=0.25;//Specific fuel consumption in kh/kW
+p1=180;//Pressure of fuel injected in bar
+d=25;//Distance travelled by crank in degrees
+p2=38;//Pressure in the combustion chamber in bar
+Cd=0.85;//Coefficient of velocity
+A=30;//API in degrees
+
+//Calculations
+T=d/(360*(N/60));//Duration of fuel injection in s
+SG=(141.5/(131.5+A))*10^3;//Specific gravity of fuel
+V=Cd*(2*(p1-p2)*10^5/SG)^(1/2);//Velocity of fuel injection in m/s
+Vf=(s/60)*P/((N/2)*SG);//Volume of fuel injected per cycle in m^3/cycle
+Na=Vf/(V*T);//Nozzle orifice area in m^2
+d=(((4*Na)/3.14)^(1/2))*10^3;//Diameter of the orifice of the fuel injector in mm
+
+//Output
+printf('The diameter of the orifice is %3.4f mm',d)
diff --git a/2063/CH7/EX7.17/7_17.sce b/2063/CH7/EX7.17/7_17.sce new file mode 100755 index 000000000..b8b5b3407 --- /dev/null +++ b/2063/CH7/EX7.17/7_17.sce @@ -0,0 +1,29 @@ +clc
+clear
+//Input data
+P=200;//Power developed by a six cylinder diesel engine in kW
+N=2000;//Operating speed of the engine in rpm
+bs=0.2;//The brake specific fuel consumption in kg/kWh
+p1=35;//The pressure of air in the cylinder at the beginning of injection in bar
+p2=55;//Maximum cylinder pressure in bar
+p3=180;//Initial injection pressure in bar
+p4=520;//Maximum pressure at the injector in bar
+Cd=0.75;//Coefficient of discharge
+S=850;//Specific gravity of fuel
+p5=1;//Atmospheric pressure in bar
+a=16;//The crank angle over which injection takes place in degrees
+
+//Calculations
+Po=P/6;//Power output per cylinder in kW
+F=(Po*bs)/60;//Fuel consumed per cylinder in kg/min
+Fi=F/(N/2);//Fuel injected per cycle in kg
+T=a/(360*(N/60));//Duration of injection in s
+deltaP1=p3-p1;//Pressure difference at the beginning of injection in bar
+deltaP2=p4-p2;//Pressure difference at the end of injection in bar
+avP=(deltaP1+deltaP2)/2;//Average pressure difference in bar
+V=Cd*(2*(avP*10^5)/S)^(1/2);//Velocity of injection of fuel jet in m/s
+Vo=Fi/S;//Volume of fuel injected per cycle in m^3/cycle
+A=(Vo/(V*T))*10^6;//Area of fuel orifices in mm^2
+
+//Output
+printf('The total orifice area required per injector if the injection takes place over 16 degree crank angle is %3.4f mm^2',A)
diff --git a/2063/CH7/EX7.18/7_18.sce b/2063/CH7/EX7.18/7_18.sce new file mode 100755 index 000000000..c07cd7ccf --- /dev/null +++ b/2063/CH7/EX7.18/7_18.sce @@ -0,0 +1,19 @@ +clc
+clear
+//Input data
+A=450;//Area of indicator diagram in mm^2
+l=60;//Length of indicator diagram in mm
+s=1.1;//Spring number in bar/mm
+d=0.1;//Diameter of piston in m
+L=0.13;//Length of stroke in m
+N=400;//Operating speed of the engine in rpm
+
+//Calculations
+Av=A/l;//Average height of indicator diagram in mm
+pm=Av*s;//Mean effective pressure in bar
+np=N/2;//Number of power strokes per minute for a four stroke diesel engine
+Ar=(3.14*d^2)/4;//Area of the piston in m^2
+I=(pm*10^5*L*Ar*np)/(1000*60);//Indicated power in kW
+
+//Output
+printf('(a)The indicated mean effective pressure is %3.2f bar\n (b)Indicated power is %3.2f kW',pm,I)
diff --git a/2063/CH7/EX7.19/7_19.sce b/2063/CH7/EX7.19/7_19.sce new file mode 100755 index 000000000..9128f92aa --- /dev/null +++ b/2063/CH7/EX7.19/7_19.sce @@ -0,0 +1,23 @@ +clc
+clear
+//Input data
+d=25;//Diameter of the bore in cm
+l=0.4;//Stroke length in m
+N=300;//Operating speed of the engine in rpm
+n=120;//Number of explosions per minute
+pm=6.7;//Mean effective pressure in kgf/cm^2
+Tnet=90;//Net brake load in kg
+R=0.75;//Radius of brake drum in m
+f=0.22;//Fuel supplied per minute in m^3
+C=4500;//Calorific value of fuel in kcal/m^3
+
+//Calculations
+BHP=(2*3.14*R*N*Tnet)/4500;//Brake horse power in kW
+A=(3.14*d^2)/4;//Area of the cylinder in cm^2
+IHP=(pm*l*A*n)/4500;//Indicated horse power in kW
+H=f*C;//Heat supplied by fuel per minute in kcal
+nt1=((IHP*C)/(990*427))*100;//Thermal efficiency on IHP basis in percent
+nt2=((BHP*C)/(990*427))*100;//Thermal efficiency on BHP basis in percent
+
+//Output
+printf('(a)The brake horse power is %3.2f kW\n (b)Indicated horse power is %3.3f kW\n (c)Thermal efficiency on IHP basis is %3.2f percent\n (d)Thermal efficiency on BHP basis is %3.2f percent',BHP,IHP,nt1,nt2)
diff --git a/2063/CH7/EX7.2/7_2.sce b/2063/CH7/EX7.2/7_2.sce new file mode 100755 index 000000000..abadeea7d --- /dev/null +++ b/2063/CH7/EX7.2/7_2.sce @@ -0,0 +1,16 @@ +clc
+clear
+//Input data
+N=700;//Engine speed in rpm
+D=0.6;//Diameter of brake drum in m
+d=0.05;//Diameter of rope in m
+W=35;//Dead load on the brake drum in kg
+S=4.5;//Spring balance reading in kg
+g=9.81;//Gravitational constant in N/m^2
+pi=3.14;//Mathematical constant
+
+//Calculations
+P=(((W-S)*g*pi*(D+d))/1000)*(N/60);//Power in kW
+
+//Output
+printf(' The power available at the brakes is %3.3f kW',P)
diff --git a/2063/CH7/EX7.20/7_20.sce b/2063/CH7/EX7.20/7_20.sce new file mode 100755 index 000000000..332f9922d --- /dev/null +++ b/2063/CH7/EX7.20/7_20.sce @@ -0,0 +1,29 @@ +clc
+clear
+//Input data
+D=0.6;//Brake wheel diameter of a constant speed compression ignition engine operating on four stroke cycle in m
+t=0.01;//Thickness of brake band in m
+N=500;//Operating speed of the engine in rpm
+W=20;//Load on brake band in kgf
+S=3;//Spring balance reading in kgf
+l=6.25;//Length of indicator diagram in cm
+A=4.35;//Area of indicator diagram in cm^2
+Sn=11;//Spring number in kgf/cm^2/cm
+d=10;//Diameter of the bore in cm
+L=0.13;//Length of the stroke in m
+F=0.23;//Specific fuel consumption in kg/BHP hr
+CV=10000;//Heating value of fuel in kcal/kg
+
+//Calculations
+BHP=(3.14*(D+t)*N*(W-S))/4500;//Brake horse power in kW
+MEP=(A*Sn)/l;//Mean effective pressure in kgf/cm^2
+Ar=(3.14*d^2)/4;//Area of the cylinder in cm^2
+np=N/2;//Number of explosions per minute
+IHP=(MEP*L*Ar*np)/4500;//Indicated horse power in kW
+nm=(BHP/IHP)*100;//Mechanical efficiency in percentage
+Wf=F*BHP;//Fuel consumption per hr in kg/hr
+nt=((IHP*4500*60)/(Wf*CV*427))*100;//Indicated thermal efficiency in percentage
+nb=((BHP*4500*60)/(Wf*CV*427))*100;//Brake thermal efficiency in kW
+
+//Output
+printf('(a)The brake horse power is %3.2f kW\n (b)Indicated horse power is %3.3f kW\n (c)Mechanical efficiency is %3.1f percent\n (d)Indicated thermal efficiency is %3.0f percent\n (e)Brake thermal efficiency is %3.1f percent',BHP,IHP,nm,nt,nb)
diff --git a/2063/CH7/EX7.21/7_21.sce b/2063/CH7/EX7.21/7_21.sce new file mode 100755 index 000000000..6b7a22118 --- /dev/null +++ b/2063/CH7/EX7.21/7_21.sce @@ -0,0 +1,21 @@ +clc
+clear
+//Input data
+N=1200;//Operating speed of a four cylinder engine in rpm
+BHP=25.3;//The brake horse power when all 4 cylinders are operating in kW
+T=10.5;//The average torque when one cylinder was cut out in mkgf
+CV=10000;//Calorific value of the fuel used in kcal/kg
+f=0.25;//The amount of petrol used in engine per BHP hour
+J=427;//
+
+//Calculations
+BHP1=(2*3.14*N*T)/4500;//BHP for 3 cylinders when 1 cylinder is cut out in kW
+IHP=BHP-BHP1;//IHP of one cylinder in kW
+IHPt=IHP*4;//Total IHP of the engine with 4 cylinders
+Wf=(f*BHP)/60;//Fuel used per minute in kg
+ni=((IHPt*4500)/(Wf*CV*J))*100;//Indicated thermal efficiency in percent
+nm=(BHP/IHPt)*100;//Mechanical efficiency in percent
+nb=(IHPt*nm)/100;//Brake thermal efficiency in percent
+
+//Output
+printf('The indicated thermal efficiency is %3.1f percent',ni)
diff --git a/2063/CH7/EX7.22/7_22.sce b/2063/CH7/EX7.22/7_22.sce new file mode 100755 index 000000000..8b2a7e773 --- /dev/null +++ b/2063/CH7/EX7.22/7_22.sce @@ -0,0 +1,19 @@ +clc
+clear
+//Input data
+B=32;//Brake horse power in kW with all cylinders working
+B1=21.6;//BHP with number 1 cylinder cut out in kW
+B2=22.3;//BHP with number 2 cylinder cut out in kW
+B3=22.5;//BHP with number 3 cylinder cut out in kW
+B4=23;//BHP with number 4 cylinder cut out in kW
+
+//Calculations
+I1=B-B1;//Indicated horse power of number 1 cylinder in kW
+I2=B-B2;//IHP of number 2 cylinder in kW
+I3=B-B3;//IHP of number 3 cylinder in kW
+I4=B-B4;//IHP of number 4 cylinder in kW
+I=I1+I2+I3+I4;//Total IHP of the engine in kW
+nm=(B/I)*100;//Mechanical efficiency in percent
+
+//Output
+printf('(a)The IHP of the engine is %3.1f kW\n (b)Mechanical efficiency is %3.1f percent',I,nm)
diff --git a/2063/CH7/EX7.23/7_23.sce b/2063/CH7/EX7.23/7_23.sce new file mode 100755 index 000000000..7d837c06e --- /dev/null +++ b/2063/CH7/EX7.23/7_23.sce @@ -0,0 +1,32 @@ +clc
+clear
+//Input data
+r=15;//The air fuel ratio by weight
+CV=45000;//Calorific value of fuel in kJ/kg
+nm=85;//Mechanical efficiency of 4 stroke 4 cylinder engine in percent
+na=53;//Air standard efficiency of the engine in percent
+nr=65;//Relative efficiency of the engine in percent
+nv=80;//Volumetric efficiency of the engine in percent
+r1=1.3;//Stroke to bore ratio
+p1=1;//Suction pressure in bar
+T=303;//Suction temperature in K
+S=3000;//The operating speed of the engine in rpm
+P=75;//Power at brakes in kW
+r2=1.4;//Ratio of specific heats for air
+R1=0.287;//Characteristic gas constant for air fuel mixture in kJ/kg K
+
+//Calculations
+R=(1/(1-(na/100)))^(1/(r2-1));//Compression ratio of the engine
+nti=((na/100)*(nr/100))*100;//The indicated thermal efficiency in percent
+Pi=P/(nm/100);//Indicated power in kW
+F=Pi/((nti*CV)/100);//Fuel per second injected in kg/sec
+B=F/P;//Brake specific fuel consumption in kg/kWsec
+A=1+r;//Mass of fuel mixture entering the engine foe every one kg of fuel in kg
+m=A*F;//Mass of air fuel mixture per second in kg
+V=(m*R1*T)/(p1*10^5/1000);//Volume of air fuel mixture supplied to the engine per sec
+Vs=V/(nv/100);//Swept volume per second in m^3/sec
+d=((Vs*2*60*4)/(S*3.14*r1*4))^(1/3)*1000;//Diameter of the bore in mm
+L=r1*d;//Stroke length in mm
+
+//Output
+printf('(a)Compression ratio is %3.1f \n (b)Indicated thermal efficiency is %3.1f percent\n (c)Brake specific fuel consumption is %3.7f kg/kW sec\n (d)Bore diameter of the engine is %3.1f mm\n (e)Stroke length of the engine is %3.1f mm',R,nti,B,d,L)
diff --git a/2063/CH7/EX7.24/7_24.sce b/2063/CH7/EX7.24/7_24.sce new file mode 100755 index 000000000..1afb42c7c --- /dev/null +++ b/2063/CH7/EX7.24/7_24.sce @@ -0,0 +1,44 @@ +clc
+clear
+//Input data
+d=0.3;//Diameter of the bore in m
+L=0.45;//Stroke length in m
+N=220;//Operating speed of the engine in rpm
+T=3600;//Duration of trial in sec
+F=7;//Fuel consumption in kg per minute
+CV=45000;//Calorific value of fuel in kJ/kg
+A=320;//Area of indicator diagram in mm^2
+l=60;//Length of indicator diagram in mm
+S=1.1;//Spring index in bar/mm
+W=130;//Net load on brakes in kg
+D=1.65;//Diameter of brake drum in m
+W1=500;//Total weight of jacket cooling water in kg
+t=40;//Temperature rise of jacket cooling water in degrees celsius
+t1=300;//Temperature of exhaust gases in degrees celsius
+ma=300;//Air consumption in kg
+sg=1.004;//Specific heat of exhaust gas in kJ/kgK
+sw=4.185;//Specific heat of water in kJ/kgK
+t2=25;//Room temperature in degrees celsius
+g=9.81;//gravity
+
+//Calculations
+P=(W*g*3.14*D*N)/(1000*60);//Power available at brakes in kW
+pm=(A*S)/l;//Mean effective pressure in bar
+I=(pm*10^5*L*((3.14*d^2)/4)*N)/(1000*2*60);//Indicated power developed in kW
+nm=(P/I)*100;//Mechanical efficiency in percent
+nt=(P/((F/T)*CV))*100;//Brake thermal efficiency in percent
+ni=(I/((F/T)*CV))*100;//Indicated thermal efficiency in percent
+Hs=F*CV;//Heat supplied on one hour basis
+Hp=P*T;//Heat equivalent of brake power in kJ
+Hf=I-P;//Heat lost in friction in kJ
+Hc=W1*t*sw;//Heat carried away by cooling water in kJ
+He=(ma+F)*(t1-t2)*sg;//Heat carried away by exhaust gas in kJ
+Hu=Hs-(He+Hf+Hc+He);//Heat unaccounted in kJ
+nb=(He/Hs)*100;//Heat equivalent of power at brakes in percent
+nf=(Hf/Hs)*100;//Heat lost in friction in percent
+nw=(Hc/Hs)*100;//Heat removed by jacket water in percent
+ne=(He/Hs)*100;//Heat carried away by exhaust gases in percent
+nu=(Hu/Hs)*100;//Heat unaccounted in percent
+
+//Output
+printf('(a)Power available at brakes is %3.2f kW\n (b)Indicated power developed is %3.2f kW\n (c)Mechanical efficiency is %3.2f percent\n (d)Brake Thermal efficiency is %3.2f percent\n (e)Indicated thermal efficiency is %3.2f percent',P,I,nm,nt,ni)
diff --git a/2063/CH7/EX7.25/7_25.sce b/2063/CH7/EX7.25/7_25.sce new file mode 100755 index 000000000..d195b1095 --- /dev/null +++ b/2063/CH7/EX7.25/7_25.sce @@ -0,0 +1,35 @@ +clc
+clear
+//Input data
+d=25;//The bore diameter of a single cylinder 4 stroke engine in cm
+l=0.38;//Stroke length in m
+t=3600;//Duration of test in sec
+r=19710;//Total number of revolutions
+F=6.25;//Fuel oil used in kg
+A=5.7;//Area of indicator diagram in cm^2
+L=7.6;//Length of indicator diagram in cm
+S=8.35;//Spring number in kgf/cm^3
+P=63.5;//Net load on brake drum in kg
+R=1.2;//Radius of brake drum in m
+Ww=5.7;//Rate of coolant flow in kg/min
+deltaT=44;//Temperature rise of coolant in degrees celsius
+T1=15.5;//Atmospheric temperature in degrees celsius
+As=30;//Air supplied per kg of fuel
+CV=10600;//Calorific value of fuel in kcal/kg
+Te=390;//Exhaust gas temperature in degrees celsius
+sm=0.25;//Mean specific heat of exhaust gas
+
+//Calculations
+Hs=(F*CV)/60;//Heat supplied by fuel per minute in kcal
+pm=(A*S)/L;//Mean effective pressure in kgf/cm^2
+I=(pm*l*(3.14*d^2)*r)/(4*60*2*4500);//Indicated horse power in kW
+B=(P*R*2*3.14*r)/(4500*60);//Brake horse power in kW
+Hei=(I*4500)/427;//Heat equivalent of IHP/min in kcal
+Heb=(B*4500)/427;//Heat equivalent of BHP/min in kcal
+Hf=Hei-Heb;//Heat in friction per minute in kcal
+Hc=Ww*deltaT;//Heat carried away by coolant in kcal
+We=(F+(As*F))/60;//Weight of exhaust gases per minute
+He=We*(Te-T1)*sm;//Heat carried away by exhaust gases in kcal
+
+//Output
+printf('(a)Indicated horse power is %3.2f kcal\n (b)Brake horse power developed is %3.2f kcal\n (c)Heat equivalent of friction is %3.1f kcal',I,B,Hf)
diff --git a/2063/CH7/EX7.26/7_26.sce b/2063/CH7/EX7.26/7_26.sce new file mode 100755 index 000000000..19183e330 --- /dev/null +++ b/2063/CH7/EX7.26/7_26.sce @@ -0,0 +1,21 @@ +clc
+clear
+//Input
+F=10;//Quantity of fuel supplied during the trial of a diesel engine in kg/hr
+CV=42500;//Calorific value of fuel in kJ/kg
+r=20;//Air fuel ratio
+T=20;//Ambient temperature in degrees celsius
+mw=585;//Water circulated through the gas calorimeter in litres/hr
+T1=35;//Temperature rise of water through the calorimeter in degrees celsius
+T2=95;//Temperature of gases at exit from the calorimeter in degrees celsius
+se=1.05;//Specific heat of exhaust gases in kJ/kgK
+sw=4.186;//Specific heat of water in kJ/kgK
+
+//Calculations
+M=(F/60)*(r+1);//Mass of exhaust gases formed per minute
+H=((mw/60)*sw*T1)+(M*se*(T2-T));//Heat carried away by the exhaust gases per minute in kJ/min
+Hs=(F/60)*CV;//Heat supplied by fuel per minute in kJ/min
+nh=(H/Hs)*100;//Percentage of heat carried away by the exhaust gas
+
+//Output
+printf('Percentage of heat carried away by exhaust gas is %3.2f percent',nh)
diff --git a/2063/CH7/EX7.27/7_27.sce b/2063/CH7/EX7.27/7_27.sce new file mode 100755 index 000000000..50212b06b --- /dev/null +++ b/2063/CH7/EX7.27/7_27.sce @@ -0,0 +1,36 @@ +clc
+clear
+//Input data
+F=11;//Fuel used per hour observed during the trial of a single cylinder four stroke diesel engine in kg
+mc=85;//Carbon present in the fuel in percent
+mh=14;//Hydrogen present in the fuel in percent
+mn=1;//Non combustibles present in the fuel in percent
+CV=50000;//Calorific value of fuel in kJ/kg
+Vc=8.5;//Percentage of carbon dioxide present in exhaust gas by Volumetric analysis
+Vo=10;//Oxygen present in exhaust gases in percent
+Vn=81.5;//Nitrogen present in exhaust gases in percent
+Te=400;//Temperature of exhaust gases in degrees celsius
+se=1.05;//Specific heat of exhaust gas in kJ/kg
+Pp=0.030;//Partial pressure of steam in the exhaust in bar
+Ta=20;//Ambient temperature in degrees celsius
+hs=2545.6;//Enthalpy of saturated steam in kJ/kg
+Tsa=24.1;//Saturation temperature from graph in degrees celcius
+Cp=2.1;//Specific heat in kJ/kg K
+hst=3335;//Enthalpy of super heated steam in kJ/kg
+
+//Calculations
+Ma=(Vn*mc)/(33*Vc);//Mass of air supplied per kg of fuel in kg
+Me=Ma+1;//Mass of exhaust gases formed per kg of fuel in kg
+me=(Me*F)/60;//Mass of exhaust gases formed per minute in kg
+ms=F*(mh/100);//Mass of steam formed per kg of fuel in kg
+ms1=(ms*F)/60;//Mass of steam formed per minute in kg
+mde=me-ms1;//Mass of dry exhaust gases formed per minute in kg
+H=mde*se*(Te-Ta);//Heat carried away by the dry exhaust gases per minute in kJ/min
+Es=hs+(Cp*(Te-Tsa));//Enthalpy of superheated steam in kJ/kg
+He=ms1*hst;//Heat carried away by steam in the exhaust gases in kJ/min
+Hl=H+He;//Total heat lost through dry exhaust gases and steam in kJ/min
+Hf=(F/60)*CV;//Heat supplied by fuel per minute in kJ/min
+nh=(Hl/Hf)*100;//Percentage of heat carried away by exhaust gases
+
+//Output
+printf('Percentage of heat carried away by exhaust gases is %3.1f percent',nh)
diff --git a/2063/CH7/EX7.28/7_28.sce b/2063/CH7/EX7.28/7_28.sce new file mode 100755 index 000000000..2db7de190 --- /dev/null +++ b/2063/CH7/EX7.28/7_28.sce @@ -0,0 +1,33 @@ +clc
+clear
+//Input data
+C=0.0033;//The capacity of a four stroke engine of compression ignition type
+I=13;//Average indicated power developed in kW/m^3
+N=3500;//Operating speed of the engine
+nv=80;//Volumetric efficiency in percentage
+p1=1.013;//Initial pressure in bar
+T1=298;//Initial temperature in K
+r=1.75;//Pressure ratio of the engine
+ni=75;//The isentropic efficiency in percentage
+nm=80;//mechanical efficiency in percentage
+r1=1.4;//Polytropic index
+
+//Calculations
+Vs=(N/2)*C;//Swept volume in m^3/min
+Vi=Vs*(nv/100);//Unsupercharged engine inducted volume in m^3/min
+Pb=p1*r;//Blower delivery pressure in bar
+T2s=((r)^((r1-1)/r1))*T1;//Final temperature in K
+T2=((T2s-T1)/(ni/100))+T1;//Blower delivery temperature in K
+Ve=((Pb*Vs)*T1)/(T2*p1);//Equivalent volume at 1.013 bar and 298K in m^3/min
+Vin=Ve-Vi;//Increase in inducted volume of air in m^3/min
+Pin=Vin*I;//Increase in indicated power due to extra air inducted in kW
+Pinp=((Pb-p1)*Vs*100)/60;//Increase in indicated power due to increase in induction pressure in kW
+Pt=Pin+Pinp;//Total increase in indicated power in kW
+nb=Pt*(nm/100);//Total increase in brake power efficiency in kW
+ma=(Pb*Vs*100)/(60*0.287*T2);//Mass of air delivered by the blower in kg/s
+Wb=ma*1.005*(T2-T1);//Work input to air by blower in kW
+Pb1=Wb/(nv/100);//Power required to drive the blower in kW
+Pb2=nb-Pb1;//Net increase in brake power in kW
+
+//Output
+printf('The net increase in brake power is %3.2f kW',Pb2)
diff --git a/2063/CH7/EX7.3/7_3.sce b/2063/CH7/EX7.3/7_3.sce new file mode 100755 index 000000000..09482460e --- /dev/null +++ b/2063/CH7/EX7.3/7_3.sce @@ -0,0 +1,17 @@ +clc
+clear
+//Input data
+W=950;//Load on hydraulic dynamometer in N
+C=7500;//Dynamometer constant
+f=10.5;//Fuel used per hour in kg
+h=50000;//Calorific value of fuel in kJ/kg
+N=400;//Engine speed in rpm
+
+//Calculations
+P=(W*N)/C;//Power available at the brakes in kW
+H=P*60;//Heat equivalent of power at brakes in kJ/min
+Hf=(f*h)/60;//Heat supplied by fuel per minute in kJ/min
+n=(H/Hf)*100;//Brake thermal efficiency in percentage
+
+//Output
+printf(' Brake thermal efficiency of the engine is %3.2f percent',n)
diff --git a/2063/CH7/EX7.4/7_4.sce b/2063/CH7/EX7.4/7_4.sce new file mode 100755 index 000000000..091f75785 --- /dev/null +++ b/2063/CH7/EX7.4/7_4.sce @@ -0,0 +1,20 @@ +clc
+clear
+//Input data
+n1=50.5;//Air standard efficiency in percentage
+n2=50;//Brake thermal efficiency in percentage
+N=3000;//Engine speed in rpm
+H=10500;//Heating value of fuel in kcal/kg
+T=7.2;//Torque developed in kgf*m
+B=6.3;//Bore diameter in cm
+S=0.095;//stroke in m
+
+//Calculations
+nbt=(n1/100)*(n2/100);//Brake thermal efficiency in percentage
+B1=(2*(22/7)*N*T)/4500;//Brake horse power in kW
+B2=B1/4;//Brake horse power per cylinder in kW
+Bsf=(4500*60)/(H*427*nbt);//Brake specific fuel consumption in kg/BHP hr
+bmep=(B2*4500)/(S*(3.14*B^2/4)*(N/2));//Brake mean effective pressure in kgf/cm^2
+
+//Output
+printf('(a)Specific fuel consumption is %3.3f kg/BHP hr\n (b)Brake mean effective pressure is %3.3f kgf/cm^2',Bsf,bmep)
diff --git a/2063/CH7/EX7.5/7_5.sce b/2063/CH7/EX7.5/7_5.sce new file mode 100755 index 000000000..76ac233b1 --- /dev/null +++ b/2063/CH7/EX7.5/7_5.sce @@ -0,0 +1,15 @@ +clc
+clear
+//Input data
+W=30;//The net dynamometer load in kg
+R=0.5;//Radius in m
+N=2400;//Speed in rpm
+FHP=6.5;//Engine power in hp
+
+//Calculations
+BHP=(2*3.14*R*N*W)/4500;//Brake horse power in kW
+IHP=BHP+FHP;//Indicated horse power in kW
+nm=(BHP/IHP)*100;//Mechanical efficiency in percentage
+
+//Output
+printf('Mechanical efficiency of the engine is %3.2f percent',nm)
diff --git a/2063/CH7/EX7.6/7_6.sce b/2063/CH7/EX7.6/7_6.sce new file mode 100755 index 000000000..f871f2b5f --- /dev/null +++ b/2063/CH7/EX7.6/7_6.sce @@ -0,0 +1,19 @@ +clc
+clear
+//Input data
+d=25;//Diameter of cylinder in cm
+l=0.4;//Stroke of piston in m
+N=200;//Speed in rpm
+m=10;//Misfires per minute
+M=6.2;//Mean effective pressure in kgf/cm^2
+nm=0.8;//Mechanical efficiency in percent
+
+//Calculations
+np=(N/2)-m;//Number of power strokes per minute
+A=(3.14*d^2)/4;//Area of the cylinder
+I=(M*l*A*np)/4500;//Indicated horse power in kW
+B=I*nm;//Brake horse power in kW
+F=I-B;//Friction horse power in kW
+
+//Output
+printf('(a)The indicated horse power is %3.2f kW \n (b)The brake horse power is %3.2f kW \n (c)Friction horse power is %3.2f kW',I,B,F)
diff --git a/2063/CH7/EX7.7/7_7.sce b/2063/CH7/EX7.7/7_7.sce new file mode 100755 index 000000000..1fd0baf08 --- /dev/null +++ b/2063/CH7/EX7.7/7_7.sce @@ -0,0 +1,14 @@ +clc
+clear
+//Input data
+I=5;//Indicated power developed by single cylinder of 2 stroke petrol engine
+M=6.5;//Mean effective pressure in bar
+d=0.1;//Diameter of piston in m
+
+//Calculations
+A=(3.14*d^2)/4;//Area of the cylinder
+LN=(I*1000*60)/(M*10^5*A);//Product of length of stroke and engine speed
+S=2*LN;//Average piston speed in m/s
+
+//Output
+printf('The average piston speed is %3.2f m/s',S)
diff --git a/2063/CH7/EX7.8/7_8.sce b/2063/CH7/EX7.8/7_8.sce new file mode 100755 index 000000000..3ab4c0c80 --- /dev/null +++ b/2063/CH7/EX7.8/7_8.sce @@ -0,0 +1,16 @@ +clc
+clear
+//Input data
+P=60;//Power developed by oil engine in kW
+M=6.5;//Mean effective pressure in kgf/cm^2
+N=85;//Number of explosions per minute
+r=1.75;//Ratio of stroke to bore diameter
+nm=0.8;//Mechanical efficiency
+
+//Calculations
+I=P/nm;//Indicated horse power
+d=((I*100*4*4500)/(M*r*3.14*N))^(1/3);//Bore diameter in cm
+l=r*d;//Stroke length in cm
+
+//Output
+printf('(a)Diameter of the bore is %3.2f cm \n (b)Stroke length of the piston is %3.2f cm',d,l)
diff --git a/2063/CH7/EX7.9/7_9.sce b/2063/CH7/EX7.9/7_9.sce new file mode 100755 index 000000000..5b2723e41 --- /dev/null +++ b/2063/CH7/EX7.9/7_9.sce @@ -0,0 +1,15 @@ +clc
+clear
+//Input data
+I=45;//Power developed by two cylinder internal combustion engine operating on two stroke principle
+N=1100;//Speed in rpm
+M=6;//Mean effective pressure in kgf/cm^2
+r=1.3;//Ratio of stroke to the bore
+nc=2;//Number of cylinders
+
+//Calculations
+d=((I*4500*4)/(M*(r/100)*3.14*N*nc))^(1/3);//Diameter of the bore in cm
+l=1.3*d;//Stroke length in cm
+
+//Output
+printf('(a)The bore diameter of the cylinder is %3.2f cm\n (b)Stroke length of the piston is %3.2f cm',d,l)
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