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-rwxr-xr-x2510/CH17/EX17.1/Ex17_1.sce14
-rwxr-xr-x2510/CH17/EX17.10/Ex17_10.sce38
-rwxr-xr-x2510/CH17/EX17.11/Ex17_11.sce13
-rwxr-xr-x2510/CH17/EX17.12/Ex17_12.sce32
-rwxr-xr-x2510/CH17/EX17.13/Ex17_13.sce32
-rwxr-xr-x2510/CH17/EX17.14/Ex17_14.sce13
-rwxr-xr-x2510/CH17/EX17.15/Ex17_15.sce38
-rwxr-xr-x2510/CH17/EX17.16/Ex17_16.sce31
-rwxr-xr-x2510/CH17/EX17.17/Ex17_17.sce2
-rwxr-xr-x2510/CH17/EX17.18/Ex17_18.sce17
-rwxr-xr-x2510/CH17/EX17.3/Ex17_3.sce11
-rwxr-xr-x2510/CH17/EX17.4/Ex17_4.sce15
-rwxr-xr-x2510/CH17/EX17.5/Ex17_5.sce10
-rwxr-xr-x2510/CH17/EX17.6/Ex17_6.sce18
-rwxr-xr-x2510/CH17/EX17.8/Ex17_8.sce56
15 files changed, 340 insertions, 0 deletions
diff --git a/2510/CH17/EX17.1/Ex17_1.sce b/2510/CH17/EX17.1/Ex17_1.sce
new file mode 100755
index 000000000..69e6d1ba3
--- /dev/null
+++ b/2510/CH17/EX17.1/Ex17_1.sce
@@ -0,0 +1,14 @@
+//Variable declaration:
+w1 = 1.5 //Thicknessof fin (in)
+L = 12.0 //Length of fin (in)
+w2 = 0.1 //Thickness of fin(in)
+
+//Calculation:
+Af = 2*w1*L //Face area of fin (in^2)
+At = Af + L*w2 //Total area of fin (in^2)
+
+//Result:
+printf("The face area of the fin is : %.0f in^2 ",Af)
+printf("The face area of the fin is : %.2f ft^2 .",Af/12**2)
+printf("The total area of the fin is : %.1f in^2 .",At)
+printf("The total area of the fin is : %.3f ft^2 .",At/12**2)
diff --git a/2510/CH17/EX17.10/Ex17_10.sce b/2510/CH17/EX17.10/Ex17_10.sce
new file mode 100755
index 000000000..6743c6203
--- /dev/null
+++ b/2510/CH17/EX17.10/Ex17_10.sce
@@ -0,0 +1,38 @@
+//Variable declaration:
+Do = 2.5/100 //Outside diameter of tube (m)
+t = 1/10**3 //Thickness of fin (m)
+T = 25 //Fluid temperature ( C)
+Tb = 170 //Surface temperature ( C)
+h = 130 //Heat transfer coefficient (W/m^2.K)
+k = 200 //Thermal conductivity of fin (W/m.K)
+rf = 2.75/100 //Outside radius of fin (m)
+
+//Calculation:
+ro = Do/2 //Radius of tube (m)
+Ab = 2*%pi*ro*t //Area of the base of the fin (m^2)
+Te = Tb-T //Excess temperature at the base of the fin (K)
+Q1 = h*Ab*Te //Total heat transfer rate without the fin (W)
+Bi = h*(t/2)/k //Biot number
+L = rf-ro //Fin height (m)
+rc = rf+t/2 //Corrected radius (m)
+Lc = L+t/2 //Corrected height (m)
+Ap = Lc*t //Profile area (m^2)
+Af = 2*%pi*(rc**2-ro**2) //Fin surface area (m^2)
+Qm = h*Af*Te //Maximum fin heat transfer rate (W)
+A = sqrt(Lc**3*h/(k*Ap)) //Abscissa of fin efficiency
+C = rf/ro //Curve parameter of fin efficiency
+//From figure 17.4:
+nf = 0.86 //Fin efficiency
+Qf = nf*Qm //Fin heat transfer rate (W)
+R = Te/Qf //Fin resistance (K/W)
+
+//Result:
+printf("1. The heat transfer rate without the fin is : %.2f W .",Q1)
+printf("Or, the heat transfer rate without the fin is : %.0f Btu/h .",Q1*3.412)
+printf("2. The corrected length is : %.4f m .",Lc)
+printf("3. The outer radius is : %.3f m ",rc)
+printf("4. The maximum heat transfer rate from the fin is : %.2f W .",Qm)
+printf("5. The fin efficiency is : %.0f %%",nf*100)
+printf("6. The fin heat transfer rate is : %.0f %%",Qf)
+printf("Or, the fin heat transfer rate is : %.0f %%",Qf*3.412)
+printf("7. The fin thermal resistance is : %.2f K/W .",R)
diff --git a/2510/CH17/EX17.11/Ex17_11.sce b/2510/CH17/EX17.11/Ex17_11.sce
new file mode 100755
index 000000000..66232cc78
--- /dev/null
+++ b/2510/CH17/EX17.11/Ex17_11.sce
@@ -0,0 +1,13 @@
+//Variable declaration:
+//From example 17.10:
+Qf = 64 //Fin heat transfer rate (W)
+Q1 = 1.48 //Total heat transfer rate without the fin (W)
+
+//Calculation:
+E = Qf/Q1 //Fin effectiveness
+
+//Result:
+printf("The fin effectiveness is : %.1f",E)
+if E>2 then
+ printf("Hence, the use of the fin is justified.")
+end
diff --git a/2510/CH17/EX17.12/Ex17_12.sce b/2510/CH17/EX17.12/Ex17_12.sce
new file mode 100755
index 000000000..5ef496cff
--- /dev/null
+++ b/2510/CH17/EX17.12/Ex17_12.sce
@@ -0,0 +1,32 @@
+//Variable declaration:
+w = 1 //Length of tube (m)
+S = 10/10**3 //Fin patch (m)
+//From example 17.10:
+t = 1/10**3 //Thickness of fin (m)
+ro = 0.0125 //Radius of tube (m)
+Af = 3.94*10**-3 //Fin surface area (m^2)
+Tb = 145 //Excess temperature at the base of the fin (K)
+h = 130 //Heat transfer coefficient (W/m^2.K)
+Qf = 64 //Fin heat transfer rate (W)
+
+//Calculation:
+Nf = w/S //Number of fins in tube length
+wb = w-Nf*t //Unfinned base length (m)
+Ab = 2*%pi*ro*wb //Unfinned base area (m^2)
+At =Ab+Nf*Af //Total transfer surface area (m^2)
+Qt = h*(2*%pi*ro*w*Tb) //Total heat rate without fins (W)
+Qb = h*Ab*Tb //Heat flow rate from the exposed tube base (W)
+Qft = Nf*Qf //Heat flow rate from all the fins (W)
+Qt2 = Qb+Qft //Total heat flow rate (W)
+Qm = h*At*Tb //Maximum heat transfer rate (W)
+no = Qt2/Qm //Overall fin efficiency
+Eo = Qt2/Qt //Overall effectiveness
+Rb = 1/(h*Ab) //Thermal resistance of base (K/W)
+Rf = 1/(h*Nf*Af*no) //Thermal resistance of fins (K/W)
+
+//Result:
+printf("1. The total surface area for heat transfer is : %.3f m^2 .",At)
+printf("2. The exposed tube base total heat transfer rate is : %.1f W .",Qb)
+printf("Or, the exposed tube base total heat transfer rate is : %.0f Btu/h .",Qb*3.412)
+printf("3. The overall efficiency of the surface is : %.1f %%",no*100)
+printf("4. The overall surface effectiveness is : %.2f .",Eo)
diff --git a/2510/CH17/EX17.13/Ex17_13.sce b/2510/CH17/EX17.13/Ex17_13.sce
new file mode 100755
index 000000000..4bf8728ee
--- /dev/null
+++ b/2510/CH17/EX17.13/Ex17_13.sce
@@ -0,0 +1,32 @@
+//Variable declaration:
+w = 1 //Width of single of fin (m)
+t = 2/10**3 //Fin base thickness (m)
+l = 6/10**3 //Fin length thickness (m)
+T1 = 250 //Surface temperature ( C)
+T2 = 20 //Ambient air temperature ( C)
+h = 40 //Surface convection coefficient (W/m^2.K)
+k = 240 //Thermal conductivity of fin (W/m.K)
+
+//Calculation:
+Ab = t*w //Base area of the fin (m^2)
+Te = T1-T2 //Excess temperature at the base of the fin (K)
+Qw = h*Ab*Te //Heat transfer rate without a fin (W)
+Af = 2*w*(sqrt(l**2-(t/2)**2)) //Fin surface area (m^2)
+Qm = h*Af*Te //Maximum heat transfer rate (m^2)
+Bi = h*(t/2)/k //Biot number
+Lc = l //Corrected length (m)
+Ap = l*t/2 //Profile area (m^2)
+A = sqrt((Lc**3*h)/k*Ap) //Abscissa for the fin efficiency figure
+//From figure 17.4:
+nf = 0.99 //Fin efficiency
+Qf = nf*Qm //Fin heat transfer rate (W)
+R = Te/Qf //Fin thermal resistance (K/W)
+E = Qf/Qw //Fin effectiveness
+Qm = round(Qm*10**-1)/10**-1
+
+//Result:
+printf("1. The heat transfer rate without the fin is : %.1f W .",Qw)
+printf("2. The maximum heat transfer rate from the fin is : %f W .",Qm)
+printf("3. The fin efficiency is : %.0f %%",nf*100)
+printf(" The fin thermal resistance is : %.1f C/W .",R)
+printf(" The fin effectiveness is : %.1f .",E)
diff --git a/2510/CH17/EX17.14/Ex17_14.sce b/2510/CH17/EX17.14/Ex17_14.sce
new file mode 100755
index 000000000..aa51305e2
--- /dev/null
+++ b/2510/CH17/EX17.14/Ex17_14.sce
@@ -0,0 +1,13 @@
+//Variable declaration:
+//From example 17.13:
+Qf = 108.9 //Fin heat transfer rate (W)
+Qw = 18.4 //Total heat transfer rate without the fin (W)
+
+//Calculation:
+E = Qf/Qw //Fin effectiveness
+
+//Result:
+printf("The fin effectiveness is : %.2f .",E)
+if E>2 then
+ printf("Hence, the use of the fin is justified.")
+end
diff --git a/2510/CH17/EX17.15/Ex17_15.sce b/2510/CH17/EX17.15/Ex17_15.sce
new file mode 100755
index 000000000..8a282671c
--- /dev/null
+++ b/2510/CH17/EX17.15/Ex17_15.sce
@@ -0,0 +1,38 @@
+//Variable declaration:
+Do = 50/10**3 //Outside diameter of tube (m)
+t = 4/10**3 //Thickness of fin (m)
+T = 20 //Fluid temperature ( C)
+Tb = 200 //Surface temperature ( C)
+h = 40 //Heat transfer coefficient (W/m^2.K)
+k = 240 //Thermal conductivity of fin (W/m.K)
+l = 15/10**3 //Length of fin (m)
+
+//Calculation:
+ro = Do/2 //Radius of tube (m)
+rf = ro+l //Outside radius of fin (m)
+Ab = 2*%pi*ro*t //Area of the base of the fin (m^2)
+Te = Tb-T //Excess temperature at the base of the fin (K)
+Q1 = h*Ab*Te //Total heat transfer rate without the fin (W)
+Bi = h*(t/2)/k //Biot number
+L = rf-ro //Fin height (m)
+rc = rf+t/2 //Corrected radius (m)
+Lc = L+t/2 //Corrected height (m)
+Ap = Lc*t //Profile area (m^2)
+Af = 2*%pi*(rc**2-ro**2) //Fin surface area (m^2)
+Qm = h*Af*Te //Maximum fin heat transfer rate (W)
+A = sqrt(Lc**3*h/(k*Ap)) //Abscissa of fin efficiency
+C = rf/ro //Curve parameter of fin efficiency
+//From figure 17.4:
+nf = 0.97 //Fin efficiency
+Qf = nf*Qm //Fin heat transfer rate (W)
+R = Te/Qf //Fin resistance (K/W)
+E = Qf/Q1 //Fin effectiveness
+
+//Result:
+printf("The fin efficiency is : %.0f %%",nf*100)
+printf("The fin thermal resistance is : %.1f C/W.",R)
+printf("The fin effectiveness is : %.2f .",E)
+printf("The maximum heat transfer rate from a single fin is : %.2f W .",Qm)
+if E>2 then
+ printf("Since Ef = FCP>2, the use of the fin is justified.")
+end
diff --git a/2510/CH17/EX17.16/Ex17_16.sce b/2510/CH17/EX17.16/Ex17_16.sce
new file mode 100755
index 000000000..d9192b1de
--- /dev/null
+++ b/2510/CH17/EX17.16/Ex17_16.sce
@@ -0,0 +1,31 @@
+//Variable declaration:
+Nf = 125 //Array of fins per meter
+w = 1 //Length of fin (m)
+//From example 17.15:
+t = 4/10**3 //Thickness of fin (m)
+Do = 50/10**3 //Outside diameter of tube (m)
+Af = 7.157*10**-3 //Fin surface area (m^2)
+h = 40 //Heat transfer coefficient (W/m^2.K)
+DTb = 180 //Excess temperature at the base of the fin (K)
+Qf = 50 //Fin heat transfer rate (W)
+
+//Calculation:
+ro = Do/2 //Radius of tube (m)
+wb = w-Nf*t //Unfinned exposed base length (m)
+Ab = 2*%pi*ro*wb //Area of the base of the fin (m^2)
+At = Ab+Nf*Af //Total heat transfer surface area (m^2)
+Qw = h*(2*%pi*ro*w)*DTb //Heat rate without fin (W)
+Qb = h*Ab*DTb //Heat rate from the base (W)
+Qft = Nf*Qf //Heat rate from the fin (W)
+Qt = Qb+Qft //Total heat rate (W)
+Qm = h*At*DTb //Maximum heat transfer rate (W)
+n = Qt/Qm //Overall fin efficiency
+E = Qt/Qw //Overall fin effectiveness
+Rb = 1/(h*Ab) //Thermal resistance of base ( C/W)
+Rf = 1/(h*Nf*Af*n) //Thermal resistance of fin ( C/W)
+
+//Result:
+printf("The rate of heat transfer per unit length of tube is : %.1f W .",Qt)
+printf("Or, the rate of heat transfer per unit length of tube is : %.2f kW .",Qt/10**3)
+printf("The overall fin efficiency is : %.1f %%",n*100)
+printf("The overall fin effectiveness is : %.2f .",E)
diff --git a/2510/CH17/EX17.17/Ex17_17.sce b/2510/CH17/EX17.17/Ex17_17.sce
new file mode 100755
index 000000000..22af4a2a7
--- /dev/null
+++ b/2510/CH17/EX17.17/Ex17_17.sce
@@ -0,0 +1,2 @@
+//Variable declaration:
+printf('Analytical Solution')
diff --git a/2510/CH17/EX17.18/Ex17_18.sce b/2510/CH17/EX17.18/Ex17_18.sce
new file mode 100755
index 000000000..d87459d37
--- /dev/null
+++ b/2510/CH17/EX17.18/Ex17_18.sce
@@ -0,0 +1,17 @@
+//Variable declaration:
+//From example 17.18:
+T = 250 //Base temperature of fin ( F)
+h = 15 //Convection coefficient of heat transfer (Btu/h.ft. F)
+w = 1 //Base width of fin (ft)
+t = 1 //Thickness of fin (in)
+H = 1/8 //Height of fin (in)
+l = 1 //Length of fin (in)
+Q = 357.2 //Heat transfer rate (Btu/h.ft)
+
+//Calculation:
+A = (l*w+t*w+H*w)/12 //Heat transfer area of fin (ft^2)
+Qm = h*A*(T-70) //Maximum heat transfer rate (Btu/h.ft)
+n = Q/Qm*100 //Fin efficiency
+
+//Result:
+printf("The fin efficiency is : %.1f %%",n)
diff --git a/2510/CH17/EX17.3/Ex17_3.sce b/2510/CH17/EX17.3/Ex17_3.sce
new file mode 100755
index 000000000..9556ddecd
--- /dev/null
+++ b/2510/CH17/EX17.3/Ex17_3.sce
@@ -0,0 +1,11 @@
+//Variable declaration:
+rf = 6.0/12.0 //Outside radius of fin (ft)
+ro = 4.0/12.0 //Outside radius of %pipe (ft)
+t = 0.1/12.0 //Thickness of fin (ft)
+
+//Calculation:
+Af = 2*%pi*(rf**2-ro**2) //Face area of fin (ft^2)
+At = Af + 2*%pi*rf*t //Total area of fin (ft^2)
+
+//Result:
+printf("The total fin area is : %.3f ft^2 .",At)
diff --git a/2510/CH17/EX17.4/Ex17_4.sce b/2510/CH17/EX17.4/Ex17_4.sce
new file mode 100755
index 000000000..87c3206d3
--- /dev/null
+++ b/2510/CH17/EX17.4/Ex17_4.sce
@@ -0,0 +1,15 @@
+//Variable declaration:
+L = 3.0*0.0254 //Height of fin (m)
+t = 1.0*0.0254 //Thickness of fin (m)
+h = 15.0 //Heat transfer coefficient (W/m^2.K)
+k = 300.0 //Thermal conductivity (W/m.K)
+
+//Calculation:
+Lc = L + t/2.0 //Corrected height of fin (m)
+Ap = Lc*t //Profile area of fin (m^2)
+x = sqrt((Lc**3*h)/(k*Ap)) //x-coordinate of figure 17.3
+//From figure 17.3:
+nf = 98.0 //Fin efficiency
+
+//Result:
+printf("The fin efficiency is : %f %%",nf)
diff --git a/2510/CH17/EX17.5/Ex17_5.sce b/2510/CH17/EX17.5/Ex17_5.sce
new file mode 100755
index 000000000..2ac673dba
--- /dev/null
+++ b/2510/CH17/EX17.5/Ex17_5.sce
@@ -0,0 +1,10 @@
+//Variable declaration:
+//From example 17.4:
+X = 0.1246 //X-coordinate of figure 17.3
+
+//Calculation:
+//Applying equation (A) from Table 17.3:
+Y = 4.5128*X**3 - 10.079*X**2 - 31.413*X + 101.47
+
+//Result:
+printf("The fin efficiency is : %.1f %%",Y)
diff --git a/2510/CH17/EX17.6/Ex17_6.sce b/2510/CH17/EX17.6/Ex17_6.sce
new file mode 100755
index 000000000..1ff551c5a
--- /dev/null
+++ b/2510/CH17/EX17.6/Ex17_6.sce
@@ -0,0 +1,18 @@
+//Variable declaration:
+w = 0.2/100.0 //Width of fin (m)
+t = 0.2/100.0 //Thickness of fin (m)
+L = 1.0/100.0 //Length of fin (m)
+h = 16.0 //Heat transfer coefficient (W/m^2.K)
+k = 400.0 //Thermal conductivity of fin (W/m.K)
+Tc = 100.0 //Circuit temperature ( C)
+Ta = 25.0 //Air temperature ( C)
+
+//Calculation:
+P = 4*w //Fin cross-section parameter (m)
+Ac = w*t //Cross-sectional area of fin (m^2)
+Lc = L+Ac/P //Corrected height of fin (m)
+m = sqrt((h*P)/(k*Ac)) //Location of minimum temperature (m^-1)
+Q = (sqrt(h*P*k*Ac))*(Tc-Ta)*atan(h)*(m*Lc) //Heat transfer from each micro-fin (W)
+
+//Result:
+printf("The heat transfer from each micro-fin is : %.2f W .",Q)
diff --git a/2510/CH17/EX17.8/Ex17_8.sce b/2510/CH17/EX17.8/Ex17_8.sce
new file mode 100755
index 000000000..f06516247
--- /dev/null
+++ b/2510/CH17/EX17.8/Ex17_8.sce
@@ -0,0 +1,56 @@
+//Variable declaration:
+h1 = 13.0 //Air-side heat transfer coefficient (W/m^2.K)
+A = 1.0 //Base wall area (m^2)
+L = 2.5/100 //Length of steel fins (m)
+L2 = 1.5/10**3 //Length of steel wall (m)
+k = 13.0 //Thermal conductivity of fin (W/m.K)
+k1 = 38.0 //Thermal conductivity of steel wall (W/m.K)
+h2 = 260.0 //Water side heat transfer coefficient (W/m^2.K)
+T4 = 19.0 //Air temperature ( C)
+T1 = 83.0 //Water temperature ( C)
+t = 1.3/10**3 //Thickness of steel fins (m)
+w = 1.0 //Width of wall (m)
+S = 1.3/100 //Fin pitch(m)
+
+//Calculation:
+R1 = 1/(h1*A) //Air resistance ( C/W) (part 1)
+R2 = L2/(k1*A) //Conduction resistance ( C/W)
+R3 = 1/(h2*A) //Water resistance ( C/W)
+Rt = (R1+R3) //Total resistance ( C/W) (part 2)
+Q = (T1-T4)/Rt //Total heat transfer (W)
+Nf = 1/S //Number of fins (part 3)
+Lbe = w - Nf*t //Unfinned exposed base surface
+Abe = w*Lbe //Exposed base surface area (m^2)
+Lc = L+t/2 //Corrected length (m)
+Ap = Lc*t //Profile area (m^2)
+Af = 2*w*Lc //Fin surface area (m^2)
+Bi = h1*(t/2)/k1 //Biot number
+a = sqrt(Lc**3*h1/(k*Ap)) //Abscissa of the fin efficiency
+//From figure 17.3:
+nf = 0.88 //Fin efficiency
+Rb = 1/(h1*Abe) //Air thermal resistance of base wall ( C/W)
+Rf = 1/(h1*Nf*Af*nf) //Air thermal resistance of fins ( C/W)
+RT1 = 1/(1/Rb+1/Rf) //Total outside resistance of the fin array ( C/W)
+Rt3 = RT1+R3 //Total resistance on air side fins ( C/W)
+Qt = (T1-T4)/Rt3 //Heat transfer rate on air side fins (W)
+I = (Qt/Q - 1)*100 //Percent increase in heat transfer rate to air side fins (W)
+A = sqrt(Lc**3*h2/(k1*Ap)) //Abscissa of the new fin efficiency (part 4)
+//From figure 17.3:
+nf2 = 38.0 //New fin efficiency
+Rb2 = 1/(h2*Abe) //Thermal resistance of base wall ( C/W)
+Rf2 = 1/(h2*Nf*Af*nf2) //Thermal resistance of fins ( C/W)
+Rt4 = 1/(1/Rb2+1/Rf2) //Total resistance of the finned surface ( C/W)
+Rt5 = R1+Rt4 //Total resistance on water side fins ( C/W)
+QT1 = (T1-T4)/Rt5 //Heat transfer rate on water side fins (W)
+I2 = (QT1/Q - 1)*100 //Percent increase in heat transfer rate to water side fins (W)
+
+//Result:
+if (R2<R1 | R2<R3) then
+ printf("1. The conduction resistance may be neglected.")
+else
+ printf("1. The conduction resistance can not be neglected.")
+end
+printf("2. The rate of heat transfer from water to air is : %.1f W .",Q)
+printf("3. The percent increase in steady-state heat transfer rate by adding fins to the air side of the plane wall is : %.1f %%",I)
+printf("4. The percent increase in steady-state heat transfer rate by adding fins to the water side of the plane wall is : %.1f %%",I2)
+printf("____There is a calculation mistake in book in calculating Qt(83-19/0.0214 = 2999), hence slight differences in answer______")
generated by cgit (git 2.34.1) at 2025-01-24 15:03:00 +0000