24 files changed, 364 insertions, 0 deletions

diff --git a/3685/CH18/EX18.1/Ex18_1.sce b/3685/CH18/EX18.1/Ex18_1.sce
new file mode 100644
index 000000000..7e5766770
--- /dev/null
+++ b/3685/CH18/EX18.1/Ex18_1.sce
@@ -0,0 +1,24 @@
+clc

+ho = 12 // Outside convective heat transfer coefficient in W/m^2K 

+x1 = 0.23// Thickness of brick in m

+k1 = 0.98 // Thermal conductivity of brick in W/mK

+x2 = 0.08 // Thickness of foam in m

+k2 = 0.02// Thermal conductivity of foam in W/mK

+x3 = 1.5// Thickness of wood in cm

+k3 = 0.17// Thermal conductivity of wood in W/cmK

+hi = 29// Inside convective heat transfer coefficient in W/m^2K 

+A = 90 // Total wall area in m^2

+to = 22// outside air temperature in degree Celsius

+ti = -2 // Inside air temperature in degree Celsius

+printf("\n Example 18.1\n")

+U = (1/((1/ho)+(x1/k1)+(x2/k2)+(x3*1e-2/k3)+(1/hi)))// Overall heat transfer coefficient

+Q = U*A*(to-ti) // Rate of heat transfer

+R = (1/ho)+(x1/k1)

+t2 = to-Q*R/A // Temperature at inside surface of brick

+

+printf("\n The rate of heat removal is %f W",Q)

+

+printf("\n Temperature at inside surface of brick is %f degree celcius",t2)

+

+//The answers vary due to round off error

+

diff --git a/3685/CH18/EX18.1/Ex18_1.txt b/3685/CH18/EX18.1/Ex18_1.txt
new file mode 100644
index 000000000..6aeaee358
--- /dev/null
+++ b/3685/CH18/EX18.1/Ex18_1.txt
@@ -0,0 +1,5 @@
+ 

+ Example 18.1

+

+ The rate of heat removal is 486.404842 W

+ Temperature at inside surface of brick is 20.281222 degree celcius 
\ No newline at end of file
diff --git a/3685/CH18/EX18.10/Ex18_10.sce b/3685/CH18/EX18.10/Ex18_10.sce
new file mode 100644
index 000000000..8ccdf32cb
--- /dev/null
+++ b/3685/CH18/EX18.10/Ex18_10.sce
@@ -0,0 +1,27 @@
+clc

+b = 10 // width of plate in cm

+h = 15 // Height of plate in cm

+hr = 8.72 // Radiative heat transfer coefficient in W/m^2K

+tw = 140 // temperature of wall in degree Celsius

+tf = 20 // Atmospheric temperature in degree Celsius

+v = 2.109e-5 // Coefficient of dynamic viscosity in m^2/s

+Pr = 0.692 // Prantl number

+K = 0.0305 // Thermal conductivity in W/mK

+L = 0.15 // characteristic length in m

+g = 9.81 // Gravitational acceleration in m/s^2

+

+printf("\n Example 18.10\n")

+A = 2*b*1e-2*h*1e-2 // total area of plate

+t_mean = (tw+tf)/2 +273

+B = 1/t_mean

+del_t = tw-tf

+Gr = g*B*del_t*L^3/v^2 // Grashoff number

+x = Gr*Pr

+if x<1e9 then

+    Nu = 0.59*(Gr*Pr)^0.25

+end

+hc = Nu*K/L

+Q = (hc+hr)*A*del_t // Rate of heat dissipation

+printf("\n Rate of heat dissipation is %f W",Q)

+//The answers vary due to round off error

+

diff --git a/3685/CH18/EX18.10/Ex18_10.txt b/3685/CH18/EX18.10/Ex18_10.txt
new file mode 100644
index 000000000..9df0b0436
--- /dev/null
+++ b/3685/CH18/EX18.10/Ex18_10.txt
@@ -0,0 +1,4 @@
+ 

+ Example 18.10

+

+ Rate of heat dissipation is 59.329572 W 
\ No newline at end of file
diff --git a/3685/CH18/EX18.11/Ex18_11.sce b/3685/CH18/EX18.11/Ex18_11.sce
new file mode 100644
index 000000000..8cd28c380
--- /dev/null
+++ b/3685/CH18/EX18.11/Ex18_11.sce
@@ -0,0 +1,28 @@
+clc

+d1 = 2 // Diameter of steel rod in cm

+d2 = 16 // Diameter of cylindrical furnace in cm

+e1 = 0.6 // emissivity of inner surface

+e2 = 0.85 // emissivity of rod surface

+T = 1093 // Inner surface temperature of furncae in degree celcius

+Tr1 = 427 // Initial temperature of rod in degree celcius

+Tr2 = 538 // Initial temperature of rod in degree celcius

+sigma = 5.67e-8 // Constant

+rho = 7845 // density in kg/ m^3

+c = 0.67 // Specific heat capacity in kJ/kgK

+printf("\n Example 18.11\n")

+A_ratio = d1/d2 // Surface area ratio of cylindrical bodies

+F12 = (1/((1/e1)+(A_ratio*(1/e2 -1))))

+A1 = %pi*d1*1e-2*1 // Surface area of rod

+T1 = Tr1+273

+T2 = T +273

+T3 = Tr2 +273

+Qi = sigma*A1*F12*(T1^4-T2^4)

+Qe = sigma*A1*F12*(T3^4-T2^4)

+

+Q_avg = abs((Qi+Qe)/2)

+tau = rho*c*(1e-4)*%pi*(Tr2-Tr1)/(Q_avg*(1e-3))

+

+// Time required for heating operation 

+printf("\n Time required for heating operation is %f s",tau)

+

+//The answers vary due to round off error

diff --git a/3685/CH18/EX18.11/Ex18_11.txt b/3685/CH18/EX18.11/Ex18_11.txt
new file mode 100644
index 000000000..b81de0c6d
--- /dev/null
+++ b/3685/CH18/EX18.11/Ex18_11.txt
@@ -0,0 +1,4 @@
+ 

+ Example 18.11

+

+ Time required for heating operation is 27.621984 s 
\ No newline at end of file
diff --git a/3685/CH18/EX18.12/Ex18_12.sce b/3685/CH18/EX18.12/Ex18_12.sce
new file mode 100644
index 000000000..e7272b6b8
--- /dev/null
+++ b/3685/CH18/EX18.12/Ex18_12.sce
@@ -0,0 +1,37 @@
+clc

+d1 = 10 // Diameter of inner cylinder in cm

+d2 = 20 // Diameter of outer cylinder in cm

+e1 = 0.65 // emissivity of inner surface

+e2 = 0.4 // emissivity of outer surface

+T1 = 1000 // Inner surface temperature in K

+T2 = 500 // outer suface temperature in K

+sigma = 5.67e-8 // Constant

+printf("\n Example 18.12\n")

+A1 = %pi*d1*1e-2

+A2 = %pi*d2*1e-2

+R =(((1-e1)/(e1*A1))+((1-e2)/(e2*A2))+(1/(A1*1)))

+Eb1 = sigma*T1^4

+Eb2 = sigma*T2^4

+Q = (Eb1-Eb2)/R // Net heat transfer between two cylinders

+printf("\n Net heat transfer between two cylinders is %d W/m length",Q)

+

+//The answers vary due to round off error

+clc

+d1 = 10 // Diameter of inner cylinder in cm

+d2 = 20 // Diameter of outer cylinder in cm

+e1 = 0.65 // emissivity of inner surface

+e2 = 0.4 // emissivity of outer surface

+T1 = 1000 // Inner surface temperature in K

+T2 = 500 // outer surface temperature in K

+sigma = 5.67e-8 // Constant

+printf("\n Example 18.12\n")

+A1 = %pi*d1*1e-2

+A2 = %pi*d2*1e-2

+R =(((1-e1)/(e1*A1))+((1-e2)/(e2*A2))+(1/(A1*1)))

+Eb1 = sigma*T1^4

+Eb2 = sigma*T2^4

+Q = (Eb1-Eb2)/R // Net heat transfer between two cylinders

+printf("\n Net heat transfer between two cylinders is %d W/m length",Q)

+

+//The answers vary due to round off error

+

diff --git a/3685/CH18/EX18.12/Ex18_12.txt b/3685/CH18/EX18.12/Ex18_12.txt
new file mode 100644
index 000000000..48c6cba5d
--- /dev/null
+++ b/3685/CH18/EX18.12/Ex18_12.txt
@@ -0,0 +1,4 @@
+ 

+ Example 18.12

+

+ Net heat transfer between two cylinders is 7297 W/m length 
\ No newline at end of file
diff --git a/3685/CH18/EX18.2/Ex18_2.sce b/3685/CH18/EX18.2/Ex18_2.sce
new file mode 100644
index 000000000..0a0ed6e49
--- /dev/null
+++ b/3685/CH18/EX18.2/Ex18_2.sce
@@ -0,0 +1,18 @@
+clc

+r1 = 5 // Inner radius of steel pipe in cm

+r2 = 10 // Extreme radius of inner insulation in cm

+r3 = 13// Extreme radius of outer insulation in cm

+K1 = 0.23 // Thermal conductivity of inner insulation in W/mK

+K2 = 0.37 // Thermal conductivity of outer insulation in W/mK

+hi = 58 // Inner heat transfer coefficient in W/m^2K

+h0 = 12 // Inner heat transfer coefficient in W/m^2K

+ti = 60 // Inner temperature in degree Celsius

+to = 25 // Outer temperature in degree Celsius

+L = 50 // Length of pipe in m

+

+printf("\n Example 18.2\n")

+Q =((2*%pi*L*(ti-to))/((1/(hi*r1*1e-2))+(log(r2/r1)/(K1))+(log(r3/r2)/(K2))+(1/(h0*r3*1e-2))))

+// Rate of heat transfer

+printf("\n Heat transfer rate is %f kW",Q/1e3)

+//The answers vary due to round off error

+

diff --git a/3685/CH18/EX18.2/Ex18_2.txt b/3685/CH18/EX18.2/Ex18_2.txt
new file mode 100644
index 000000000..2c994a814
--- /dev/null
+++ b/3685/CH18/EX18.2/Ex18_2.txt
@@ -0,0 +1,4 @@
+ 

+ Example 18.2

+

+ Heat transfer rate is 2.335196 kW
\ No newline at end of file
diff --git a/3685/CH18/EX18.3/Ex18_3.sce b/3685/CH18/EX18.3/Ex18_3.sce
new file mode 100644
index 000000000..71919c225
--- /dev/null
+++ b/3685/CH18/EX18.3/Ex18_3.sce
@@ -0,0 +1,32 @@
+clc

+to = 20 // Environment temperature in degree Celsius

+t = 100// Temperature of steam path in degree Celsius

+ta1 =  26.76 // Temperature at other end in degree Celsius for rod A 

+d = 10 // diameter of rod in mm

+L = 0.25 // length of rod in m

+h = 23 // heat transfer coefficient in W/m^2 K

+tb1 =  32.00 // Temperature at other end in degree Celsius for rod B 

+tc1 =  36.93 // Temperature at other end in degree Celsius for rod C 

+

+printf("\n Example 18.3\n")

+A = %pi/4 * (d*1e-3)^2 //Area of rod

+p = %pi*d*1e-3 // perimeter of rod

+// For rod A

+a = (ta1-to)/(t-to) 

+ma = (acosh(1/a))/L

+

+Ka = (h*p)/(ma^2*A) // Thermal conductivity of rod A

+printf("\n Thermal conductivity of rod A is %f W/mK",Ka)

+// For rod B

+b = (tb1-to)/(t-to) 

+mb = (acosh(1/b))/L

+

+Kb = (h*p)/(mb^2*A) // Thermal conductivity of rod B

+printf("\n Thermal conductivity of rod B is %f W/mK",Kb)

+c = (tc1-to)/(t-to) 

+mc = (acosh(1/c))/L

+

+Kc = (h*p)/(mc^2*A) // Thermal conductivity of rod A

+printf("\n Thermal conductivity of rod C is %d W/mK",ceil(Kc))

+//The answers vary due to round off error

+

diff --git a/3685/CH18/EX18.3/Ex18_3.txt b/3685/CH18/EX18.3/Ex18_3.txt
new file mode 100644
index 000000000..27e95a398
--- /dev/null
+++ b/3685/CH18/EX18.3/Ex18_3.txt
@@ -0,0 +1,6 @@
+ 

+ Example 18.3

+

+ Thermal conductivity of rod A is 57.496967 W/mK

+ Thermal conductivity of rod B is 86.076212 W/mK

+ Thermal conductivity of rod C is 116 W/mK 
\ No newline at end of file
diff --git a/3685/CH18/EX18.4/Ex18_4.sce b/3685/CH18/EX18.4/Ex18_4.sce
new file mode 100644
index 000000000..376c63658
--- /dev/null
+++ b/3685/CH18/EX18.4/Ex18_4.sce
@@ -0,0 +1,19 @@
+clc

+h = 17.4 // Convective heat transfer coefficient in W/m^2K

+K = 52.2 // Thermal conductivity in W/mK

+t = 120 // Heat reservoir wall temperature in degree celcius

+t0 = 35 // Ambient temperature in degree celcius

+L = 0.4 // Lenght of rod in m

+b  = .050 // width of rod in mm

+H = .050 // Heigth of rod in mm

+

+printf("\n Example 18.4\n")

+l= L/2

+A = b*H

+m = sqrt(4*h*b/(K*b*H))

+t1 = (t-t0)/cosh(m*l) + t0 // Midway temperature of rod

+Q1 = 2*5.12*K*A*(t-t0)*tanh(m*l) // Heat loss rate 

+printf("\n Midway temperature of rod is %f degree Celcius",t1)

+printf("\n Heat loss rate is %fW",Q1)

+//The answers vary due to round off error

+

diff --git a/3685/CH18/EX18.4/Ex18_4.txt b/3685/CH18/EX18.4/Ex18_4.txt
new file mode 100644
index 000000000..543fbdb44
--- /dev/null
+++ b/3685/CH18/EX18.4/Ex18_4.txt
@@ -0,0 +1,5 @@
+ 

+ Example 18.4

+

+ Midway temperature of rod is 88.713878 degree Celcius

+ Heat loss rate is 88.033160W 
\ No newline at end of file
diff --git a/3685/CH18/EX18.5/Ex18_5.sce b/3685/CH18/EX18.5/Ex18_5.sce
new file mode 100644
index 000000000..b74a76cff
--- /dev/null
+++ b/3685/CH18/EX18.5/Ex18_5.sce
@@ -0,0 +1,22 @@
+clc

+d = 8 // Average diameter in mm

+r = 750 // Density in Kg/m^3

+t = 2 // Intermediate temperature in degree celcius

+t_inf = 1 // Ambient temperature in degree celcius

+t0 = 25 // Initial temperature in degree celcius

+c = 3.35 // Specific heat in kJ/KgK

+h = 5.8 // Heat transfer coeeficient in W/m^2K

+T1 = 10 // time period in minutes

+T2 = 30 // time period in minutes 

+t1 = 5 // Intermediate temperature in degree celcius

+printf("\n Example 18.5\n")

+tau1 = c*1e3*log((t0-t_inf)/(t-t_inf))/(h*60) // Time to cool down to 2 degree celcius

+tau2 = (t0-t_inf)*(exp(-(c*T1*60)/(c*1e3))) // Temperature of peas after 10 minutes

+Y = exp(-1*(c*T2*60)/(c*1e3))

+tau3 = (t0*Y-t1)/(Y-1)

+

+printf("\n Time to cool down to 2 degree celcius is %f min",tau1)

+printf("\n Temperature of peas after 10 minutes is %f degree celcius",tau2)

+printf("\n Temperature of peas after 30 minutes is %f degree celcius",tau3)

+//The answers given in book are incorrect

+

diff --git a/3685/CH18/EX18.5/Ex18_5.txt b/3685/CH18/EX18.5/Ex18_5.txt
new file mode 100644
index 000000000..9370628ec
--- /dev/null
+++ b/3685/CH18/EX18.5/Ex18_5.txt
@@ -0,0 +1,6 @@
+ 

+ Example 18.5

+

+ Time to cool down to 2 degree celcius is 30.593334 min

+ Temperature of peas after 10 minutes is 13.171479 degree celcius

+ Temperature of peas after 30 minutes is 1.039327 degree celcius
\ No newline at end of file
diff --git a/3685/CH18/EX18.6/Ex18_6.sce b/3685/CH18/EX18.6/Ex18_6.sce
new file mode 100644
index 000000000..f8e87ed80
--- /dev/null
+++ b/3685/CH18/EX18.6/Ex18_6.sce
@@ -0,0 +1,22 @@
+clc

+mh =  1000 // mass flow rate of hot fluid in Kg/h

+mc = 1000 // mass flow rate of cold fluid in Kg/h

+ch = 2.09 // Specific heat capacity of hot fluid in kJ/kgK

+cc = 4.187 //Specific heat capacity of cold fluid in kJ/kgK 

+th1 = 80// Inlet temperature of hot fluid in degree celcius

+th2 = 40 // Exit temperature of hot fluid in degree Celsius

+tc1 = 30 // Inlet temperature of cold fluid in degree Celsius

+U = 24 // heat transfer coefficient in W/m^2K

+

+printf("\n Example 18.6\n")

+Q = mh*ch*(th1-th2)

+tc2 = Q/(mc*cc) + tc1// outlet temperature of cold fluid

+te = th2-tc1 // Exit end temperature difference in degree Celsius

+ti = th1 - tc2 // Inlet end temperature  difference in degree Celsius

+t_lm = (ti-te)/(log(ti/te))

+A = Q / (U*t_lm*3.6) // Surface are of heat exchanger

+

+printf("\n Surface area of heat exchanger is %f m^2",A)

+

+//The answers vary due to round off error

+

diff --git a/3685/CH18/EX18.6/Ex18_6.txt b/3685/CH18/EX18.6/Ex18_6.txt
new file mode 100644
index 000000000..3be0a0d94
--- /dev/null
+++ b/3685/CH18/EX18.6/Ex18_6.txt
@@ -0,0 +1,4 @@
+

+ Example 18.6

+

+ Surface area of heat exchanger is 53.115547 m^2
\ No newline at end of file
diff --git a/3685/CH18/EX18.7/Ex18_7.sce b/3685/CH18/EX18.7/Ex18_7.sce
new file mode 100644
index 000000000..ca630dc1a
--- /dev/null
+++ b/3685/CH18/EX18.7/Ex18_7.sce
@@ -0,0 +1,23 @@
+clc

+Hfg = 2257 // Latent heat at 100 degree Celsius

+

+ma =  500 // mass flow rate of air in Kg/h

+ch = 1.005 // Specific heat capacity of hot air in kJ/kgK

+ta1 = 260 // Inlet temperature of hot air in degree Celsius

+ta2 = 150 // Inlet temperature of cold air in degree Celsius

+tc1 = 100 // Inlet temperature of steam

+tc2 = tc1 // Exit temperature of steam

+U = 46 // heat transfer coefficient in W/m^2K

+

+printf("\n Example 18.7\n")

+Q = ma*ch*(ta1-ta2)

+m = Q/Hfg // mass flow rate of steam

+te = ta2-tc1 // Exit end temperature difference in degree Celsius

+ti = ta1 - tc2 // Inlet end temperature  difference in degree Celsius

+t_lm = (ti-te)/(log(ti/te))

+A = Q / (U*t_lm*3.6) // Surface are of heat exchanger

+

+printf("\n Surface area of heat exchanger is %f m^2",A)

+

+//The answers vary due to round off error

+

diff --git a/3685/CH18/EX18.7/Ex18_7.txt b/3685/CH18/EX18.7/Ex18_7.txt
new file mode 100644
index 000000000..ff3459f4f
--- /dev/null
+++ b/3685/CH18/EX18.7/Ex18_7.txt
@@ -0,0 +1,4 @@
+ 

+ Example 18.7

+

+ Surface area of heat exchanger is 3.529488 m^2 
\ No newline at end of file
diff --git a/3685/CH18/EX18.8/Ex18_8.sce b/3685/CH18/EX18.8/Ex18_8.sce
new file mode 100644
index 000000000..1ce2d2b5c
--- /dev/null
+++ b/3685/CH18/EX18.8/Ex18_8.sce
@@ -0,0 +1,37 @@
+clc

+mh =  20.15 // mass flow rate of hot fluid in Kg/s

+mc = 5.04 // mass flow rate of cold fluid in Kg/h

+ch = 2.094 // Specific heat capacity of hot fluid in kJ/kgK

+cc = 4.2 //Specific heat capacity of cold fluid in kJ/kgK 

+th1 = 121// Inlet temperature of hot fluid in degree Celsius

+th2 = 40 // Exit temperature of hot fluid in degree Celsius

+tc1 = 10 // Inlet temperature of cold fluid in degree Celsius

+U = 0.34 // heat transfer coefficient in kW/m^2K

+n = 200 // total number of tubes

+l = 4.87 // length of tube in m

+d = 1.97 // Outer diameter in cm

+printf("\n Example 18.8\n")

+A = %pi*n*d*1e-2*l // Total surface area

+mc_oil = mh*ch

+mc_water = mc*cc

+ c_min = mc_water

+    c_max =mc_oil

+    

+if mc_oil<mc_water then

+    c_min = mc_oil

+    c_max =mc_water

+end

+

+R = c_min/c_max

+NTU = U*A/c_min

+e = (1-exp(-1*NTU*(1-R)))/(1-R*exp(-1*NTU*(1-R)))

+t_larger = e*(th1-tc1)

+t_water = t_larger 

+t_oil = t_water*mc_water/mc_oil

+th2 = th1 - t_oil // Exit temperature of oil

+Q = mh*ch*(th1-th2) // Rate of heat transfer

+

+printf("\n Exit temperature of oil is %f degree celcius",th2)

+printf("\n Rate of heat transfer is %d kW",Q)

+//The answers vary due to round off error

+

diff --git a/3685/CH18/EX18.8/Ex18_8.txt b/3685/CH18/EX18.8/Ex18_8.txt
new file mode 100644
index 000000000..58c45a4da
--- /dev/null
+++ b/3685/CH18/EX18.8/Ex18_8.txt
@@ -0,0 +1,5 @@
+ 

+ Example 18.8

+

+ Exit temperature of oil is 90.125103 degree celcius

+ Rate of heat transfer is 1302 kW 
\ No newline at end of file
diff --git a/3685/CH18/EX18.9/Ex18_9.sce b/3685/CH18/EX18.9/Ex18_9.sce
new file mode 100644
index 000000000..2bb42384d
--- /dev/null
+++ b/3685/CH18/EX18.9/Ex18_9.sce
@@ -0,0 +1,19 @@
+clc

+u_m = 0.8 // mean velocity in m/s

+D = 5 // Diameter in cm

+v = 4.78e-7 // dynamic coefficient of viscosity

+Pr = 2.98 // Prantl number

+K = 0.66 // Thermal conductivity in W/mK

+l = 3 // length of pipe in m

+tw = 70 // Wall temperature

+tf = 50 // mean water temperature

+printf("\n Example 18.9\n")

+Re = u_m*D*1e-2/v // Reynold number

+Nu = 0.023*(Re^0.8)*(Pr^0.4)

+h = K*Nu/(D*1e-2) // Heat transfer coefficient

+A = %pi*D*1e-2*l // Surface area

+Q = h*A*(tw-tf) // Rate of heat transfer

+printf("\n Heat transfer coefficient is %d W/m^2K",h)

+printf("\n Rate of heat transfer is %f kW",Q/1e3)

+//The answers vary due to round off error

+

diff --git a/3685/CH18/EX18.9/Ex18_9.txt b/3685/CH18/EX18.9/Ex18_9.txt
new file mode 100644
index 000000000..355877b57
--- /dev/null
+++ b/3685/CH18/EX18.9/Ex18_9.txt
@@ -0,0 +1,5 @@
+ 

+ Example 18.9

+

+ Heat transfer coefficient is 4074 W/m^2K

+ Rate of heat transfer is 38.402993 kW
\ No newline at end of file