7 files changed, 213 insertions, 0 deletions
diff --git a/2657/CH27/EX27.1/Ex27_1.sce b/2657/CH27/EX27.1/Ex27_1.sce
new file mode 100755
index 000000000..17d27deff
--- /dev/null
+++ b/2657/CH27/EX27.1/Ex27_1.sce
@@ -0,0 +1,26 @@
+//Calculations on non supercharged CI engine
+clc,clear
+//Given:
+Pr=500 //Standard reference brake power in kW
+eta_m=85 //Mechanical efficiency in percent
+br=220 //Standard specific fuel consumption in g/kWh
+px=87 //Site ambient air pressure in kPa
+Tx=45+273 //Site ambient temperature in K
+phix=80/100 //Relative humidity at site
+//Solution:
+//Refer table 27.1, 27.2 and 27.3
+a=1 //Factor
+m=1,n=0.75,q=0 //Exponents
+psx=9.6 //Saturation vapour pressure at site in kPa
+psr=3.2 //Standard saturation vapour pressure in kPa
+pr=100 //Standard total barometric pressure in kPa
+Tr=298 //Standard air temperature in K
+phir=0.3 //Standard relative humidity
+k=((px-a*phix*psx)/(pr-a*phir*psr))^m*(Tr/Tx)^n //The ratio of indicated power
+alpha=k-0.7*(1-k)*(100/eta_m-1) //Power adjustment factor
+Beta=k/alpha //Fuel consumption adjustment factor
+Px=alpha*Pr //Brake power at site in kW
+bx=Beta*br //Specific fuel consumption at site in g/kWh
+//Results:
+printf("\n The site continuous net brake power, Px = %.1f kW",Px)
+printf("\n The site continuous specific fuel consumption, bx = %.1f g/kWh\n",bx)
diff --git a/2657/CH27/EX27.2/Ex27_2.sce b/2657/CH27/EX27.2/Ex27_2.sce
new file mode 100755
index 000000000..e30219abb
--- /dev/null
+++ b/2657/CH27/EX27.2/Ex27_2.sce
@@ -0,0 +1,30 @@
+//Calculations on turbocharged CI engine
+clc,clear
+//Given:
+Pr=1000 //Standard reference brake power in kW
+eta_m=90 //Mechanical efficiency in percent
+Pir=2 //Boost pressure ratio
+Tra=313 //Substitute reference air temperature in K
+Pimax=2.36 //Maximum boost pressure ratio
+h=4000 //Altitude in m
+px=61.5 //Site ambient air pressure in kPa
+Tx=323 //Site ambient temperature in K
+Tcx=310 //Charge air coolent temperature at site in K
+//Solution:
+//Refer table 27.1, 27.2 and 27.3
+m=0.7,n=1.2,q=1 //Exponents
+pr=100 //Standard total barometric pressure in kPa
+Tcr=298 //Standard charge air coolent temperature in K
+Tr=298 //Standard air temperature in K
+pra=pr*Pir/Pimax //Standard reference pressure in kPa
+pra=round(10*pra)/10
+k=(px/pra)^m*(Tra/Tx)^n*(Tcr/Tcx)^q //The ratio of indicated power
+alpha=k-0.7*(1-k)*(100/eta_m-1) //Power adjustment factor
+Px1=round(alpha*Pr) //Brake power at site in kW
+//If reference conditions are not changed
+k=(px/pr)^m*(Tr/Tx)^n*(Tcr/Tcx)^q //The ratio of indicated power
+alpha=k-0.7*(1-k)*(100/eta_m-1) //Power adjustment factor
+Px2=round(alpha*Pr) //Brake power at site in kW
+//Results:
+printf("\n Power available at an altitude of 4000m, Px = %d kW",Px1)
+printf("\n Power available at an altitude of 4000m if reference conditions are not changed, Px = %d kW\n",Px2)
diff --git a/2657/CH27/EX27.3/Ex27_3.sce b/2657/CH27/EX27.3/Ex27_3.sce
new file mode 100755
index 000000000..7450ea1e7
--- /dev/null
+++ b/2657/CH27/EX27.3/Ex27_3.sce
@@ -0,0 +1,27 @@
+//Calculations on turbocharged CI engine
+clc,clear
+//Given:
+Px=640 //Brake power at site in kW
+px=70 //Site ambient air pressure in kPa
+Tx=330 //Site ambient temperature in K
+Tcx=300 //Charge air coolent temperature at site in K
+eta_m=85 //Mechanical efficiency in percent
+py=100 //Test ambient pressure in kPa
+Tcy=280 //Charge air coolent temperature at test in K
+Ty=300 //Test ambient temperature in K
+//Solution:
+//Refer table 27.1, 27.2 and 27.3
+m=0.7,n=1.2,q=1 //Exponents
+pr=100 //Standard total barometric pressure in kPa
+Tcr=298 //Standard charge air coolent temperature in K
+Tr=298 //Standard air temperature in K
+kr=(px/pr)^m*(Tr/Tx)^n*(Tcr/Tcx)^q //The ratio of indicated power
+kr=floor(1000*kr)/1000
+alphar=kr-0.7*(1-kr)*(100/eta_m-1) //Power adjustment factor
+Pr=Px/alphar //Standard reference brake power in kW
+ky=(py/pr)^m*(Tr/Ty)^n*(Tcr/Tcy)^q //The ratio of indicated power at test
+alphay=ky-0.7*(1-ky)*(100/eta_m-1) //Power adjustment factor at test
+Py=Pr*alphay //Brake power at test in kW (Round off error)
+//Results:
+printf("\n Power developed under test ambient conditions, Py = %.0f kW",Py)
+//Round off error in the value of 'Py'
diff --git a/2657/CH27/EX27.4/Ex27_4.sce b/2657/CH27/EX27.4/Ex27_4.sce
new file mode 100755
index 000000000..78712b62e
--- /dev/null
+++ b/2657/CH27/EX27.4/Ex27_4.sce
@@ -0,0 +1,29 @@
+//Simulating site ambient conditions
+clc,clear
+//Given:
+//Datas are taken from Ex. 27.3
+Px=640 //Brake power at site in kW
+eta_m=85 //Mechanical efficiency in percent
+px=70 //Site ambient air pressure in kPa
+py=100 //Standard total barometric pressure in kPa
+Tx=330 //Site ambient temperature in K
+Ty=300 //Test ambient temperature in K
+p2_py=2.5 //Pressure ratio
+by=238 //Specific fuel consumption at test in g/kWh
+//Solution:
+//Refer table 27.1, 27.2 and 27.3
+m=0.7,n=1.2,q=1 //Exponents
+ky=(py/px)^m //The ratio of indicated power at test
+alphay=ky-0.7*(1-ky)*(100/eta_m-1) //Power adjustment factor at test
+Py=round(Px*alphay) //Brake power at test in kW
+//From fig 27.1
+Tx_Ty=Tx/Ty //Temperature ratio
+p1_py=0.925 //Ratio
+p1=p1_py*py //Air pressure after throttle in kPa (printing error)
+Betay=ky/alphay //Fuel consumption adjustment factor at test
+bx=by/Betay //Specific fuel consumption at site in g/kWh
+//Results:
+printf("\n Power developed on the test bed, Py = %d kW",Py)
+printf("\n The pressure behind the throttle plate, p1 = %.1f kPa",p1)
+printf("\n The fuel consumption adjusted to site ambient conditions, bx = %d g/kWh",bx)
+//Answer in the book is printed wrong
diff --git a/2657/CH27/EX27.5/Ex27_5.sce b/2657/CH27/EX27.5/Ex27_5.sce
new file mode 100755
index 000000000..f1df1d157
--- /dev/null
+++ b/2657/CH27/EX27.5/Ex27_5.sce
@@ -0,0 +1,18 @@
+//Calculations on unsupercharged SI engine
+clc,clear
+//Given:
+Py=640 //Brake power at test in kW
+py=98 //Test ambient pressure in kPa
+Ty=303 //Test ambient temperature in K
+phiy=0.8 //Relative humidity at test
+//Solution:
+//Refer table 27.1, 27.3
+psy=4.2 //Saturation vapour pressure at test in kPa
+psr=3.2 //Standard saturation vapour pressure in kPa
+pr=100 //Standard total barometric pressure in kPa
+Tr=298 //Standard air temperature in K
+phir=0.3 //Standard relative humidity
+alpha_a=((pr-phir*psr)/(py-phiy*psy))^1.2*(Ty/Tr)^0.6 //Correction factor for CI engine
+Pr=round(alpha_a*Py) //Standard reference brake power in kW
+//Results:
+printf("\n The power at standard reference conditions, Pr = %d kW",Pr)
diff --git a/2657/CH27/EX27.6/Ex27_6.sce b/2657/CH27/EX27.6/Ex27_6.sce
new file mode 100755
index 000000000..b9b165f49
--- /dev/null
+++ b/2657/CH27/EX27.6/Ex27_6.sce
@@ -0,0 +1,33 @@
+//Calculations on turbocharged CI engine
+clc,clear
+//Given:
+Py=896 //Brake power at test in kW
+py=96 //Test ambient pressure in kPa
+Ty=302 //Test ambient temperature in K
+phiy=0.2 //Relative humidity at test
+px=98 //Site ambient air pressure in kPa
+Tx=315 //Site ambient temperature in K
+phix=0.4 //Relative humidity at site
+N=1800 //Engine speed in rpm
+V_s=51.8 //Swept volume in litres
+m_f=54.5 //Fuel delivery in gm/s
+pi=2.6 //Pressure ratio
+//Solution:
+//Refer table 27.1, 27.3
+psy=4.8 //Saturation vapour pressure at test in kPa
+psx=8.2 //Saturation vapour pressure at site in kPa
+q=m_f*1000/(N/(2*60)*V_s) //Fuel delivery in mg/litrecycle
+qc=round(q/pi) //Corrected fuel delivery inmg/litrecycle
+//Applying condition given in fig 27.2 for value of engine factor (fm)
+if (qc <= 40) then
+    fm=0.3;
+elseif (qc >= 65) then
+    fm=1.2;
+else
+    fm=0.036*qc-1.14;
+end
+fa=((px-phix*psx)/(py-phiy*psy))^0.7*(Ty/Tx)^1.5 //Atmospheric factor
+alpha_d=fa^fm //Correction factor for CI engine
+Px=alpha_d*Py //Brake power at site in kW
+//Results:
+printf("\n Power at site ambient conditions, Px = %d kW",Px)
diff --git a/2657/CH27/EX27.7/Ex27_7.sce b/2657/CH27/EX27.7/Ex27_7.sce
new file mode 100755
index 000000000..4cf5203eb
--- /dev/null
+++ b/2657/CH27/EX27.7/Ex27_7.sce
@@ -0,0 +1,50 @@
+//Calculations on turbocharged CI engine
+clc,clear
+//Given:
+Py=700 //Brake power at test in kW
+py=96 //Test ambient pressure in kPa
+Ty=302 //Test ambient temperature in K
+phiy=0.2 //Relative humidity at test
+px=69 //Site ambient air pressure in kPa
+Tx=283 //Site ambient temperature in K
+phix=0.4 //Relative humidity at site
+N=1200 //Engine speed in rpm
+V_s=45 //Swept volume in litres
+m_f=51.3 //Fuel delivery in gm/s
+pi=2.0 //Pressure ratio
+eta_m=85 //Mechanical efficiency in percent
+//Solution:
+pr=100 //Standard total barometric pressure in kPa
+Tr=298 //Standard air temperature in K
+phir=0.3 //Standard relative humidity
+//Refer table 27.1, 27.3
+psy=4.1 //Saturation vapour pressure at test in kPa
+psx=1.2 //Saturation vapour pressure at site in kPa
+psr=3.2 //Standard saturation vapour pressure in kPa
+q=m_f*1000/(N/(2*60)*V_s) //Fuel delivery in mg/litrecycle
+qc=round(q/pi) //Corrected fuel delivery in mg/litrecycle
+//Applying condition given in fig 27.2 for value of engine factor (fm)
+if (qc <= 40) then
+    fm=0.3;
+elseif (qc >= 65) then
+    fm=1.2;
+else
+    fm=0.036*qc-1.14;
+end
+fa=((px-phix*psx)/(py-phiy*psy))^0.7*(Ty/Tx)^1.5 //Atmospheric factor
+alpha_d=fa^fm //Correction factor for CI engine
+//Applying condition given in section 27.4.2
+if (alpha_d > 0.9) & (alpha_d < 1.1) then
+    Px=alpha_d*Py
+else
+    fa=((pr-phir*psr)/(py-phiy*psy))^0.7*(Ty/Tr)^1.5 //Atmospheric factor
+    alpha_d=fa^fm //Correction factor for CI engine
+    Pr=alpha_d*Py //Standard reference brake power in kW
+    m=0.7,n=2 //Exponents
+    k=(px/pr)^m*(Tr/Tx)^n //The ratio of indicated power
+    alpha=k-0.7*(1-k)*(100/eta_m-1) //Power adjustment factor
+    Px=alpha*Pr //Brake power at site in kW
+end
+//Results:
+printf("\n Power at site ambient conditions, Px = %d kW",Px)
+//Answer in the book is wrong