diff options
Diffstat (limited to '686')
32 files changed, 696 insertions, 0 deletions
diff --git a/686/CH1/EX1.1/Ex1_1.sci b/686/CH1/EX1.1/Ex1_1.sci new file mode 100755 index 000000000..8bc2fcc85 --- /dev/null +++ b/686/CH1/EX1.1/Ex1_1.sci @@ -0,0 +1,14 @@ +clc();
+clear;
+
+// To calculate the overall thermal resistance and overall heat transfer coefficient
+
+b = 0.5/12; // Thickness of iron wall in ft
+k = 30; // Thermal conductivity in Btu/hr-ft
+h1 = 2; // Heat transfer coefficient in Btu/hr-ft
+h2 = 2; // Heat transfer coefficient in Btu/hr-ft
+R = (1/h1)+(1/h2)+(b/k); // Overall thermal resistance*Area in hr-F/Btu ie. (R/A)
+U = 1/R; // Overall heat transfer coeficient in Btu/hr-ft^2-F
+
+printf("The overall thermal resistance is %.4f/A hr-F/Btu/A, where A is the area of wall \n",R);
+printf(" The overall heat transfer coefficient is %d Btu/hr-ft^2-F",round(U));
\ No newline at end of file diff --git a/686/CH1/EX1.2/Ex1_2.sci b/686/CH1/EX1.2/Ex1_2.sci new file mode 100755 index 000000000..f16dbbe73 --- /dev/null +++ b/686/CH1/EX1.2/Ex1_2.sci @@ -0,0 +1,14 @@ +clc();
+clear;
+
+// To calculate the thermal resistance
+
+b1 = 0.5/12; // Thickness of iron wall in ft
+b2 = 0.0005/12; // Thickness of air gap in ft
+b3 = 1/12; // Thickness of aluminium wall in ft
+k1 = 30; // Thermal conductivity in Btu/hr-ft^2-F
+k2 = 0.015; // Thermal conductivity in Btu/hr-ft^2-F
+k3 = 118; // Thermal conductivity in Btu/hr-ft^2-F
+R = (b1/k1)+(b2/k2)+(b3/k3); // Thermal resistance*Area
+
+printf("The overall thermal resistance of composite wall is %f/A hr-F/Btu, A being the area of wall in ft^2",R);
\ No newline at end of file diff --git a/686/CH1/EX1.3/Ex1_3.sci b/686/CH1/EX1.3/Ex1_3.sci new file mode 100755 index 000000000..7c960e7a7 --- /dev/null +++ b/686/CH1/EX1.3/Ex1_3.sci @@ -0,0 +1,57 @@ +clc();
+clear;
+
+// To calculate the size of heating surface
+
+m1 = 100; // Flow rate of water in lb/hr
+ta1 = 50; // Initial temperature of water in F
+ta2 = 170; // Final temperature of water
+Cp1 = 1; // Heat capacity of water in Btu/lb-F
+te1 = 330; // Initial temperatutre in flue gases in F
+m2 = 400; // Mass flow rate of flue gases in lb/hr
+Cp2 = .25; // Heat capacity of flue gases in Btu/lb-F
+q = m1*Cp1*(ta2-ta1); // Heat absorbed by water in Btu
+te2 = te1-q/(m2*Cp2); // Final temperature of flue gases in F
+U = 20; // Overall heat transfer in Btu/hr-ft^2-F
+
+// For parallel flow
+delte = te1-ta1; // Flue tempearture difference in F
+delta = te2-ta2; // Water temperature difference in F
+
+// Seeing the value of delte/delta=7, we can attain the value of a
+a1 = 0.77;
+deltm = (delte + delta)/2; // Arithmetic mean in F
+LMTD1 = a1*deltm; // Log mean temperature diffference
+A1 = q/(U*LMTD1); // Area in ft^2
+printf("The area of heat exchanger for parallel flow is %.2f ft^2 \n ",A1);
+
+// for counterflow
+delte = te1-te2; // Flue tempearture difference in F
+delta = ta1-ta2; // Water temperature difference in F
+
+// Seeing the value of delte/dela=1, a=1.
+a2 = 1;
+LMTD2 = a2*deltm; // Log mean temperature diffference
+A2 = q/(U*LMTD2); // Area in ft^2
+printf("The area of heat exchanger for counterflow flow is %.2f ft^2 \n ",A2);
+
+// For cross flow
+delte = te1-ta1; // Flue tempearture difference in F
+delta = te2-ta2; // Water temperature difference in F
+
+// Seeing the value of delta/delte=0.143, we can attain the value of a=0.939
+a3 = 0.939;
+deltm = (delte + delta)/2; // Arithmetic mean in F
+LMTD3 = a3*deltm; // Log mean temperature diffference
+A3 = q/(U*LMTD3); // Area in ft^2
+printf("The area of heat exchanger for cross flow is %.2f ft^2 \n ",A3);
+
+
+
+
+
+
+
+
+
+
diff --git a/686/CH10/EX10.1/Ex10_1.sci b/686/CH10/EX10.1/Ex10_1.sci new file mode 100755 index 000000000..9c7a82bdf --- /dev/null +++ b/686/CH10/EX10.1/Ex10_1.sci @@ -0,0 +1,24 @@ +clc();
+clear;
+
+// To calculate the heat transfer coefficient from the plate to the air
+
+Tw = 196; // Temperature of plate in F
+Ts = 79; // Temperature of the air in F
+u = 587; // velocity in air in fps
+x = 4/12; // Length of plate in ft
+n = 20.4*10^-5; // Kinematic velocity
+Cp = 1200; // Specific heat capacity
+Re = u*x/n; // Reynolds number
+r = 0.845; // Temperature recovery factor
+tr = Ts+r*u*u/Cp; // Dynamic temperature in F
+Pr = 0.697; // Pradtls number
+p = 0.0657; // Density in lb/ft^3
+t = 144.1; // Corresponding temperature in F
+St = 0.0296*(Re)^-(1/5)/(1+1.75*0.87*(Re)^-(1/10)*(Pr-1));
+// Strantons number
+
+h = p*u*St*3600; // Heat transfer coefficient
+hav = 1.215*h; // Average heat transfer coefficient
+
+printf("The heat transfer coefficient from the palte to the air is %.1f Btu/hr-ft^2-F",hav);
diff --git a/686/CH11/EX11.1/Ex11_1.sci b/686/CH11/EX11.1/Ex11_1.sci new file mode 100755 index 000000000..6595c114a --- /dev/null +++ b/686/CH11/EX11.1/Ex11_1.sci @@ -0,0 +1,26 @@ +clc();
+clear;
+
+// To calculate the local heat transfer coefficient
+
+Ts = 200; // Temperature of steam in F
+Ta = 68; // Air temerature in F
+n = 24.21*10^-5; // Kinematic viscosity in ft^2/sec
+k = 0.0181; // Thermal conductivity in Btu/hr-ft-F
+g = 32.2; // Gravity
+b = 1/528; // Expansion coefficient
+x = 8/12; // Distance from lower end
+th = Ts-Ta; // Temperature difference in F
+Gr = g*b*th*x^3/(n^2); // Grashops number
+Pr = 0.694; // Prandtls number
+del = x*3.93*Pr^(-0.5)*((0.952+Pr)^1/4)*Gr^(-0.25);
+// Boundary layer thickness
+h = 2*k/del; // film heat transfer coefficient
+hav = 4*h/3; // Avg heat transfer cioefficient
+printf("The average heat transfer coefficient over the length of 8 in. is %.2f Btu/hr-ft^2-F",h);
+
+
+
+
+
+
diff --git a/686/CH12/EX12.1/Ex12_1.sci b/686/CH12/EX12.1/Ex12_1.sci new file mode 100755 index 000000000..55379e6d4 --- /dev/null +++ b/686/CH12/EX12.1/Ex12_1.sci @@ -0,0 +1,21 @@ +clc();
+clear;
+
+ // To calculate the heat transfer coefficient
+
+L = 1029; // Heat of evaporation in Btu/lb
+n = 0.654*10^-5; // Kinematic viscosity in Btu/hr-ft-F
+p = 62; // density in lb/ft^3
+k = 0.367; // Thermal conductivity in Btu/hr-ft^2-F
+g = 32.2; // Gravity
+x = 3/12; // Distance from upper edge in ft
+ts = 114; // Saturation temperature in F
+tw = 105; // Wall temperature in F
+
+h = (g*k^3*p*L*3600/(4*n*x*(ts-tw)))^0.25; // Heat transfer coefficient
+hav = h*4/3; // Avg heat transfer coefficient
+
+printf("The average heat transfer coefficient is %d Btu/hr-ft^2-F",hav);
+
+
+
diff --git a/686/CH12/EX12.2/Ex12_2.sci b/686/CH12/EX12.2/Ex12_2.sci new file mode 100755 index 000000000..f72d30f58 --- /dev/null +++ b/686/CH12/EX12.2/Ex12_2.sci @@ -0,0 +1,15 @@ +clc();
+clear;
+
+ // To calculate the heat exchange by radiatiojn between two walls
+
+ t1 = 2500; // Temperature of saturated steam in F
+ t2 = 600; // External temperature of tube walls in F
+ e = 0.8; // Emmisivity of tube wall arrangement
+ p = 0.87; // Emperical factor
+ A = 148.5; // Area of the wall in ft^2
+ s = 0.173*10^-8; // Stephens boltzmanns constant
+ q = s*e*A*p*(((t1+460)^4)-((t2+460)^4)); // heat loss in Btu/hr
+
+ printf("The heat exchange per unit area is %.2f Btu/hr",q);
+
\ No newline at end of file diff --git a/686/CH14/EX14.1/Ex14_1.sci b/686/CH14/EX14.1/Ex14_1.sci new file mode 100755 index 000000000..870c1eea2 --- /dev/null +++ b/686/CH14/EX14.1/Ex14_1.sci @@ -0,0 +1,14 @@ +clc();
+clear;
+
+ // To calculate the heat exchange by radiation between two walls
+
+ t1 = 212; // Temperature of contents in the bottle in F
+ t2 = 68; // Ambient temperature in F
+
+ e = 0.02 ; // Emmisivity of silver
+ e12 = 1/(2/e-1); // Exchange factor
+ s = 0.173*10^-8; // Stephens boltzmanns constant
+
+ q = s*e12*((t1+460)^4-(t2+460)^4); // Heat loss in Btu/hr
+ printf("The heat flow per unit area of the inner wall is %.2f Btu/hr-ft^2",q);
\ No newline at end of file diff --git a/686/CH14/EX14.2/Ex14_2.sci b/686/CH14/EX14.2/Ex14_2.sci new file mode 100755 index 000000000..bee1a9ebc --- /dev/null +++ b/686/CH14/EX14.2/Ex14_2.sci @@ -0,0 +1,22 @@ +clc();
+clear;
+
+ // To calculate the heat exchange by radiation between two walls
+
+ t1 = 2500; // Temperature of saturated steam in F
+ t2 = 600; // Temperature of tube wall in F
+ p = 0.87; // Emperical factor
+ A = 148.5; // Area of tube walls
+ A1 = 168.8; // Area of walls lined with cooling tubes
+ e = 0.8 ; // Emmisivity of silver
+ s = 0.173*10^-8; // Stephens boltzmanns constant
+
+ q = p*s*e*A*((t1+460)^4-(t2+460)^4); // Heat loss in Btu/hr
+ L = 649.4; // Latent heat of vapourization in Btu/lb
+ m = q/L; // Generation of steam in lb/hr
+ A2 = A1*%pi/2; // Area of tube in ft^2
+ h = q/A2; // Heat absorption rate
+ printf("The heat absorption per square foot of tube area is %d Btu/hr-ft^2" ,h);
+
+
+
\ No newline at end of file diff --git a/686/CH14/EX14.3/Ex14_3.sci b/686/CH14/EX14.3/Ex14_3.sci new file mode 100755 index 000000000..416611e49 --- /dev/null +++ b/686/CH14/EX14.3/Ex14_3.sci @@ -0,0 +1,55 @@ +clc();
+clear;
+
+// To find the division of the heating surface
+ t1 = 2500; // temperature of contenets of the bottle in F
+ t2 = 600; // Ambient temperature in F
+ e1 = 0.048; // Interchange factor in 1800 F
+ e2 = 0.044; // Interchange factor in 600 F
+ e = 0.94; // Emmisivity of walls
+ p = 1; // Emperical factor
+ F = 2*0.88; // Shape factor
+ s = 0.173*10^-8; // Stephens boltzmanns constant
+
+ h = s*e*p*F*((t1+460)^4-(t2+460)^4)/(%pi*(t1-t2));
+ // Heat transfer coefficient
+
+
+ // Heat transfer for the tubes within the convective surface
+ // Radiation of CO2 and waterin the combustion gases
+ L = 0.5; // Eqivalent length of gas layer
+ Tg = 1800; // Gas temperature in F
+ Tw = 600; // Surface temperature of tubes in F
+
+ // From the table the emmisivity of carbon dioxide can be known
+ ec1 = 0.06; // Emmmisivity of CO2 at 1800F
+ ec2 = 0.055; // Emmisivity of Co2 at 600F
+ ew = 0.8; // Emmisivity of tube wall
+ qc = s*ew*p*(ec1*(Tg+460)^4-ec2*(t2+460)^4);
+ // Heat loss by carbon dioxide in Btu/hr
+
+// From the table the emmisivity of water can be known
+ eh1 = 0.0176; // Emmmisivity of water at 1800F
+ eh2 = 0.0481; // Emmisivity of water at 600F
+ qh = s*ew*p*(eh1*(Tg+460)^4-eh2*(t2+460)^4);
+ // Heat loss by water in Btu/hr
+
+ qg = qc + qh; // Heat heat flow by gas radiation
+ hg = qg/(Tg-t2); // Heat transfer coeffcoent by gas radiation
+ printf("The heat transfer coefficient by gas radiation is %.2f Btu/hr-ft^2 \n",hg);
+
+ // Heat transfer by convection can be found out using values iun the table
+ hc = 8.14; // Heat transfer by convection in Btu/hr-ft^2-F
+ printf(" The heat transfer coefficient by gas radiation is %.2f Btu/hr-ft^2\n",hc);
+
+ ht = hc + hg; // Total heat transfer coefficient for convective surface
+
+ printf("The covective surface have greater heat transfer coefficients than the radiating surface. Therefore it is advantageous to line the whole combustion chamber with narrowly spaced cooling tubes");
+
+
+
+
+
+
+
+
\ No newline at end of file diff --git a/686/CH16/EX16.1/Ex16_1.sci b/686/CH16/EX16.1/Ex16_1.sci new file mode 100755 index 000000000..3d7104d97 --- /dev/null +++ b/686/CH16/EX16.1/Ex16_1.sci @@ -0,0 +1,16 @@ +clc();
+clear;
+
+// To calculate the siffusion coefficient
+
+ T = 87.5; // Constant temperature of tube
+ p1 = 0.6543; // Saturation pressure in psi
+ p = 14.22; // Ambient pressure
+ e = 5.165*10^-5; // Rate of evaporation in lb/hr
+ A = 0.755; // Area of tube in in^2
+ m = e*144/A; // Mass flux in lb/hr-ft^2
+ M = 18.0165; // Molecular weight of water
+ R = 1545/M; // Gas constant
+ l = 2.527/12; // Length of tube in ft
+ D = m*R*(T+460)*l/(p*144*log(p/(p-p1))); // Diffusion coefficient
+ printf("The diffusion coefficient of water vapour over air is %.3f ft^2/hr",D)
\ No newline at end of file diff --git a/686/CH16/EX16.2/Ex16_2.sci b/686/CH16/EX16.2/Ex16_2.sci new file mode 100755 index 000000000..f95f7b70e --- /dev/null +++ b/686/CH16/EX16.2/Ex16_2.sci @@ -0,0 +1,28 @@ +clc();
+clear;
+
+// To calculatevthe amount of water evaporated per hour per square feet from the water surface
+
+u = 10; // Flow of air stream in fps
+r = 33.3; // Relative humidity
+T = 519; // Temperature in Rankine
+p = 0.1130; // Partial pressure of water vapour
+x = 4/12; // Water surface in the wind direction
+n = 15.99*10^-5; // Kinematic viscosity
+k = 0.0149; // Thermal conductivity in Btu/hr-ft-F
+Re = u*x/n; // reynolds number
+D = 1.127; // Diffusion coefficient in ft^2/sec
+R = 85.74; // Gas constant in Imperial in Imperial units
+
+hd =0.664*Re^0.5*(n*3600/D)^(1/3)*D/x; // Heat transfer coefficient
+Pr = 0.710; // Prandtls number
+Nu = 0.664*sqrt(Re)*Pr^(1/3); // Nusselt number
+h = Nu*k/x; // Heat transfer coefficient
+ps = 0.2473; // Saturation pressure of water vapour
+m = hd*(ps-p)*144/(R*T); // Water vapour formation rate in lb/hr-ft^2
+
+printf("The rate of amount of water evaporated per sq. foot is %.3f lb/hr-ft^2",m);
+
+
+
+
diff --git a/686/CH16/EX16.3/Ex16_3.sci b/686/CH16/EX16.3/Ex16_3.sci new file mode 100755 index 000000000..a25e879ea --- /dev/null +++ b/686/CH16/EX16.3/Ex16_3.sci @@ -0,0 +1,14 @@ +clc();
+clear;
+
+// To determine the specific heat of air
+
+p = 14.7; // Pressure in psi.
+Tb = 68; // Dry bulb temperature in F
+Tw = 50; // Wet bulb temperature in F
+
+// In the enthalpy-specific heat diagram, the isotherm 50F in the supersaturated region must be extended until it intersects the isotherm 68F.
+// The point of intersection gives the state of moist air and its specific heat capacity can be read
+s = 0.0037; // Specific heat capacity
+
+printf("Tne specific humidity of air is %.4f lb of water per pound of dry air",s);
diff --git a/686/CH3/EX3.1/Ex3_1.sci b/686/CH3/EX3.1/Ex3_1.sci new file mode 100755 index 000000000..01c060bcb --- /dev/null +++ b/686/CH3/EX3.1/Ex3_1.sci @@ -0,0 +1,21 @@ +clc();
+clear;
+
+// To calculate the length of the well
+
+d = 0.06/12; // diameter of the thermometer in ft
+h = 18.5; // heat teansfer coefficient in Btu/hr-ft^2-F
+k = 32; // Thermal conductivity in Btu/hr-ft^2-F
+s = 0.036/12; // thickness of wall in ft
+m = sqrt(h/(k*s)); // parameter
+
+// Error is less than 0.05% of the dfference between the gas temperature and the tube well temperature. Hence a=m*l
+
+a = 6; // a=m*l
+l = a/m; // Length of well in ft
+printf("The length of well is %.2f ft",l)
+
+
+
+
+
diff --git a/686/CH3/EX3.2/Ex3_2.sci b/686/CH3/EX3.2/Ex3_2.sci new file mode 100755 index 000000000..918a84877 --- /dev/null +++ b/686/CH3/EX3.2/Ex3_2.sci @@ -0,0 +1,23 @@ +clc();
+clear;
+
+// To determine the effectiveness of iron fins of 0.14 inch thickness
+// For heat transfer to air
+b = 0.12/12; // Thickness of iron fins in ft
+k = 33; // Mean thermal conductivity of iron in Btu/hr-ft^2
+Hamin = 2; // Minimum heat ransfer coefficient with air in Btu/hr-ft^2-F
+Hamax = 20; // Minimum heat ransfer coefficient with air in Btu/hr-ft^2-F
+// Inserting the higher value of heat transfer coefficient
+m1 = 2*k/(Hamax*b); // Characteristic value
+// haracteristic value is quite high
+printf("Since m = %d, hence the heat transfer from iron fins to air is advantageous \n",m1);
+
+// For heat transfer to water
+
+Hwmin = 100; // Minimum heat ransfer coefficient with air in Btu/hr-ft^2-F
+Hwmax = 1000; // Minimum heat ransfer coefficient with air in Btu/hr-ft^2-F
+// Inserting the higher value of heat transfer coefficient
+m2 = 2*k/(Hwmax*b); // Characteristic value
+// Characteristic value is quite low
+printf("Since m = %.1f, hence the heat transfer from iron fins to water is not advantageous \n",m2);
+
diff --git a/686/CH3/EX3.3/Ex3_3.sci b/686/CH3/EX3.3/Ex3_3.sci new file mode 100755 index 000000000..724522ec4 --- /dev/null +++ b/686/CH3/EX3.3/Ex3_3.sci @@ -0,0 +1,32 @@ +clc();
+clear;
+
+// To study the effect of adding fins to the cylindrical barrel of an air cooled engine
+
+l1= 3/12; // Length of fins in ft
+l2 = 4/12;
+h = 50; // Heat transfer coefficient in Btu/hr-ft-F
+k = 28; // Thermal conductivity in Btu/hr-ft-F
+T1 = 250; // Cylinder wall temperature in F
+T2 = 70; // Air temperature in F
+th = T1-T2; // Temperature difference
+b = 0.09/12; // Thickness of fins in ft
+m = 2*h/(b*k); // Characteristic parameter
+// Seeing the value of length and m, yhe bessel functions can be found out
+
+I2 = 188/7.26; // Magnitudes of bessel functions
+I0 = 41.0/5.45;
+I1 = 37.2/5.45;
+K2 = 0.0;
+K0 = 0.0022/5.45;
+K1 = 0.0024/5.45;
+
+q1 = 2*%pi*0.27*k*sqrt(m)*th*(I2*l2*m*K1*l1-K2*l2*m*I1*l1)/(144*(I2*l2*sqrt(m)*K0*l1*sqrt(m)+K2*l2*sqrt(m)*I0*l1*sqrt(m)));
+// Heat loss by finned surface
+q2 = 0.27/144*2*%pi*3*h*th; // heat loss from barred surface
+
+printf("the heat loss from the cylindrical barrel in presence of fins is %d Btu/hr \n ",q1);
+printf("the heat loss from the bare cylindrical barrel is %d Btu/hr \n ",q2)
+
+
+
\ No newline at end of file diff --git a/686/CH3/EX3.4/Ex3_4.sci b/686/CH3/EX3.4/Ex3_4.sci new file mode 100755 index 000000000..724522ec4 --- /dev/null +++ b/686/CH3/EX3.4/Ex3_4.sci @@ -0,0 +1,32 @@ +clc();
+clear;
+
+// To study the effect of adding fins to the cylindrical barrel of an air cooled engine
+
+l1= 3/12; // Length of fins in ft
+l2 = 4/12;
+h = 50; // Heat transfer coefficient in Btu/hr-ft-F
+k = 28; // Thermal conductivity in Btu/hr-ft-F
+T1 = 250; // Cylinder wall temperature in F
+T2 = 70; // Air temperature in F
+th = T1-T2; // Temperature difference
+b = 0.09/12; // Thickness of fins in ft
+m = 2*h/(b*k); // Characteristic parameter
+// Seeing the value of length and m, yhe bessel functions can be found out
+
+I2 = 188/7.26; // Magnitudes of bessel functions
+I0 = 41.0/5.45;
+I1 = 37.2/5.45;
+K2 = 0.0;
+K0 = 0.0022/5.45;
+K1 = 0.0024/5.45;
+
+q1 = 2*%pi*0.27*k*sqrt(m)*th*(I2*l2*m*K1*l1-K2*l2*m*I1*l1)/(144*(I2*l2*sqrt(m)*K0*l1*sqrt(m)+K2*l2*sqrt(m)*I0*l1*sqrt(m)));
+// Heat loss by finned surface
+q2 = 0.27/144*2*%pi*3*h*th; // heat loss from barred surface
+
+printf("the heat loss from the cylindrical barrel in presence of fins is %d Btu/hr \n ",q1);
+printf("the heat loss from the bare cylindrical barrel is %d Btu/hr \n ",q2)
+
+
+
\ No newline at end of file diff --git a/686/CH3/EX3.5/Ex3_5.sci b/686/CH3/EX3.5/Ex3_5.sci new file mode 100755 index 000000000..37f2a4f23 --- /dev/null +++ b/686/CH3/EX3.5/Ex3_5.sci @@ -0,0 +1,20 @@ +clc;
+clear;
+
+// To find the tempearure difference in the plane wall with heat sources
+d1 = 0.55; // Inside diameter of copper wire
+d2 = 0.8; // Outside diameter of copper wire
+phi = 0.6; // Fraction of copper in wire
+j = 1300; // Current density in conductors in amp/in^2
+p = 9.5*10^(-6); // Specific resistance in ohm-in^2/ft
+h = 4; // Heat transfer coefficient on both sides ofcoil
+k = 0.2; // Thermal conductivity of coil in Btu/hr-ft-F
+T0 = 70; // Temperature of air in degF
+// Considering it as a plane wall with a thickness of 0.25 ft
+b = 0.125; // half the thickness of wall in ft
+l = 0.0625; // Distance between the two walls
+q = j*j*p*phi*144*3.412; // Generation of heat in Btu/hr-ft-F
+th0 = (4730*l*l/(2*k))+(4730*l/h); // Teperature difference in F
+t0 = T0+th0; // Temperature at the center in F
+
+printf("The temperature at the centre of the pool is %.1f degF \n",t0);
diff --git a/686/CH3/EX3.6/Ex3_6.sci b/686/CH3/EX3.6/Ex3_6.sci new file mode 100755 index 000000000..25c202bd9 --- /dev/null +++ b/686/CH3/EX3.6/Ex3_6.sci @@ -0,0 +1,11 @@ +clc();
+clear;
+
+// To determine the shape factor for the heat flow through a square duct whose surface temperatures are constant
+
+// Since the duct is symmetrical. Only one of the corners is to be considered
+Nc = 20; // Number of heat flow lanes
+Nr = 7; // Number of temperature increments
+S = Nc/Nr; // Shape factor
+printf("The Shape factor for heat flow through square duct is %.2f \n ",S);
+printf("And the heat transfer through conduction is %.2f kL(t1-t2)",S);
\ No newline at end of file diff --git a/686/CH4/EX4.1/Ex4_1.sci b/686/CH4/EX4.1/Ex4_1.sci new file mode 100755 index 000000000..713288c36 --- /dev/null +++ b/686/CH4/EX4.1/Ex4_1.sci @@ -0,0 +1,17 @@ +clc();
+clear;
+
+// To measure an unsteady state temperature with a thermometer and half value time
+
+// Half value time is the time within which the initial difference etween the true and indicated temperature is reduced to half its initial value
+
+l = 0.01/2; // Length of cylindrical tube in ft
+a = 0.178; // Thermal diffusivity in ft^2/hr
+k = 5; // Thermal conductivity in Btu/hr-ft-F
+h = 10; // Heat transfer coefficient in Btu/hr-ft^2-F
+Bi = h*l/k; // Biot number
+
+// For half time
+th = 0.693*l*l*3600/(Bi*a); // Half time in hr
+
+printf("The half time for unsteady change temperature change is %d sec",th);
diff --git a/686/CH4/EX4.2/Ex4_2.sci b/686/CH4/EX4.2/Ex4_2.sci new file mode 100755 index 000000000..b33e1511e --- /dev/null +++ b/686/CH4/EX4.2/Ex4_2.sci @@ -0,0 +1,14 @@ +clc();
+clear;
+
+// To calculate the lag of thermometer used in initial example while the oven is heating
+
+r = 0.01; // Radius of cylindrical tube in ft
+a = 0.178; // Thermal diffusivity in ft^2/hr
+k = 5; // Thermal conductivity in Btu/hr-ft-F
+h = 2; // Heat transfer coefficient in Btu/hr-ft^2-F
+s = 400; // Rate of temperature change
+tlag = r*k*s/(2*a*h);
+
+printf("The lag of thermometer while the oven is heating at the rate of 400F/hr is %.1f F",tlag);
+
diff --git a/686/CH4/EX4.3/Ex4_3.sci b/686/CH4/EX4.3/Ex4_3.sci new file mode 100755 index 000000000..402983582 --- /dev/null +++ b/686/CH4/EX4.3/Ex4_3.sci @@ -0,0 +1,32 @@ +clc();
+clear
+
+// To find the time required for the billet to remain in the oven
+
+A = 2; // Length of steel billet in ft
+B = 2; // Breadth of billet in ft
+C = 4; // Height of billet in ft
+To = 70; // Initial temperature of billet n F
+Tf = 750; // Maximum temp. of billet in F
+T = 700; // Temperature for which time has to be found out
+k = 25; // Thermal conductivity in Btu/hr-ft^2-F
+a = 0.57; // Thermal diffusivity in ft^2/hr
+h = 100; // Heat transfer coeff. in Btu/hr-ft
+
+BiA = h*A/k; // Biot number
+BiB = h*B/k;
+BiC = h*C/k;
+t = 1.53; // Assumed temperature in F
+s1 = a*t/A^2; // Parameters
+s2 = a*t/B^2;
+s3 = a*t/C^2;
+
+// Seeing the values of Bi and s and comparing from the table
+
+// T/Toa=0.302 and T/Tob=0.805 and (T/Toa)^2*T/Toc=0.0735
+
+printf("The time required for the centre temperature to reach 700 F under the conditions specified in the problem is t=%.2f hr",t);
+
+
+
+
\ No newline at end of file diff --git a/686/CH4/EX4.4/Ex4_4.sci b/686/CH4/EX4.4/Ex4_4.sci new file mode 100755 index 000000000..d49eb69a6 --- /dev/null +++ b/686/CH4/EX4.4/Ex4_4.sci @@ -0,0 +1,16 @@ +clc();
+clear;
+
+// To calculate the time needed to estabilish a steady state temperature distribution in the walls and in the room
+tf = 70; // Final temperature of the wall in F
+hi = 1.2; // Inner heat transfer coefficint of wall i Btu/hr-ft^2-degF
+ho = 3.0; // Outer heat transfer coefficient in Btu/hr-ft^2-degF
+a = 0.012; // Thermal diffusivity in ft^2/hr
+x = 1.3; // Thickness of wall in ft
+
+// Assuming the rate of heat trasfer to the inside of a wall is constant
+// And since the wall is divided into six sections
+delx = x/6; // Thickness of sections in ft
+t = (delx)^2/(2*a); // time required in hr
+printf("the time needed to estabilish a steady state temperature distribution in the walls and in the room is %.2f hr",t);
+
diff --git a/686/CH4/EX4.5/Ex4_5.sci b/686/CH4/EX4.5/Ex4_5.sci new file mode 100755 index 000000000..184d05907 --- /dev/null +++ b/686/CH4/EX4.5/Ex4_5.sci @@ -0,0 +1,13 @@ +clc();
+clear;
+
+// To calculate the depth and yearly temperature fluctuations penetrate the ground
+
+a = 0.039; // thermal diffusivity of claylike soil
+to = 24; // time for daily fluctuations in hr
+x = 1.6*sqrt(%pi*a*to); // depth of penetration for daily fluctuation in ft
+xy = sqrt(365)*x; // depth of penetration for yearly fluctuation in ft
+
+printf("The depth of penetration for daily fluctuation is %.2f ft and depth of penetration for yearly fluctuation is %.2f ft",x, xy);
+
+
\ No newline at end of file diff --git a/686/CH4/EX4.6/Ex4_7.sci b/686/CH4/EX4.6/Ex4_7.sci new file mode 100755 index 000000000..74950f8d6 --- /dev/null +++ b/686/CH4/EX4.6/Ex4_7.sci @@ -0,0 +1,13 @@ +clc();
+clear;
+
+// To calculate the depth of penetration of the temperature oscillation into the cylinder wall
+
+rpm = 2000; // Revolutions per minute of motor
+a = 0.64; // Thermal diffusivity in ft^2/hr
+to = 1/(60*rpm); // Period of oscillation in hr
+x = 1.6*sqrt(%pi*a*to); // depth of penetration in hr
+printf("the depth of penetration of the temperature oscillation into the cylinder wall is %.5f ft",x);
+
+
+
\ No newline at end of file diff --git a/686/CH4/EX4.7/Ex4_7.sci b/686/CH4/EX4.7/Ex4_7.sci new file mode 100755 index 000000000..74950f8d6 --- /dev/null +++ b/686/CH4/EX4.7/Ex4_7.sci @@ -0,0 +1,13 @@ +clc();
+clear;
+
+// To calculate the depth of penetration of the temperature oscillation into the cylinder wall
+
+rpm = 2000; // Revolutions per minute of motor
+a = 0.64; // Thermal diffusivity in ft^2/hr
+to = 1/(60*rpm); // Period of oscillation in hr
+x = 1.6*sqrt(%pi*a*to); // depth of penetration in hr
+printf("the depth of penetration of the temperature oscillation into the cylinder wall is %.5f ft",x);
+
+
+
\ No newline at end of file diff --git a/686/CH6/EX6.1/Ex6_1.sci b/686/CH6/EX6.1/Ex6_1.sci new file mode 100755 index 000000000..683bd9c83 --- /dev/null +++ b/686/CH6/EX6.1/Ex6_1.sci @@ -0,0 +1,12 @@ +clc();
+clear;
+
+//*****Data*****//
+x = 4/12;// [thickness of plate, inch]
+v = 33;// [fps]
+n = 15.4*10^(-5);// [kinematic viscosity, feet^2/s]
+//************//
+
+Re = v*x/n;// [Reynold's number]
+delta = 4.64*x*12/sqrt(Re);// [Boundary layer thickness ,ft]
+printf("Boundary layer thickness at 4 in. distance is %.4f in.",delta);
\ No newline at end of file diff --git a/686/CH6/EX6.2/Ex6_2.sci b/686/CH6/EX6.2/Ex6_2.sci new file mode 100755 index 000000000..4df22b604 --- /dev/null +++ b/686/CH6/EX6.2/Ex6_2.sci @@ -0,0 +1,12 @@ +clc();
+clear;
+
+// To calculate the thickness of turbulent boundary layer at a distance of 12 inch
+x = 12/12; // Distance from leading edge in ft
+v = 33; // Stream flowing velocity in ft
+n = 15.4*10^(-5); // kinematic viscosity, feet^2/s
+
+Re = v*x/n ; // reynolds number
+delta = 0.376*x/(Re^0.2); // Boundary layer thickness ,ft
+delb = 0.036*delta*12; // Turbulent layer thickness, in
+printf("The turbulent boundarty layer thickness is %.3f ft",delb);
\ No newline at end of file diff --git a/686/CH7/EX7.1/Ex7_1.sci b/686/CH7/EX7.1/Ex7_1.sci new file mode 100755 index 000000000..0ec6eb9ed --- /dev/null +++ b/686/CH7/EX7.1/Ex7_1.sci @@ -0,0 +1,24 @@ +clc();
+clear;
+
+
+// to calculate the heat tranaferv coefficient for a plate in an air stream
+
+x = 4/12; // distance from leading edge in ft
+u = 33; // air velocity in fps
+Ts = 125; //
+Tw = 255; // surface temperature in F
+k = 0.0178; // Thermal conductivity in Btu/hr-ft-F
+Re = 46600; // Reynolds number
+Pr = 0.695; // Prandtls number
+
+Nu = 0.332*Re^.5*Pr^(1/3); // Nusselt number
+h = Nu*k/x; // Local heat transfer coefficient
+ha = h*12; // Heat transfer coefficient average
+b = 1; // Width of plate in ft
+x = 4/12; // Length of plate
+
+q = ha*b*x*(Ts-Tw); // Heat loss in Btu/hr
+
+printf("The heat transfer coefficient for a plate in an air stream is %.2f Btu/hr-ft^2-F ",h);
+
diff --git a/686/CH8/EX8.1/Ex8_1.sci b/686/CH8/EX8.1/Ex8_1.sci new file mode 100755 index 000000000..9a83e10fc --- /dev/null +++ b/686/CH8/EX8.1/Ex8_1.sci @@ -0,0 +1,20 @@ +clc();
+clear;
+
+// To find the amount of heat transferred to the air
+
+Tw = 200; // Wall temperature in F
+delp = 14.2; // Pressure pressure in lb/in^2
+d = 0.8/12; // Diameter in ft
+R = delp*%pi*d^2/4; // resistance of tube
+Tb = 137; // bulk temperature of wall in F
+
+q = R*32.2*0.24*3600*(Tw-Tb)/100; // Heat loss in Btu/hr
+printf("The heat loss from the tube well to the air when the plate is heated to a temperature of 200 F is %d Btu/hr",q);
+
+
+
+
+
+
+
\ No newline at end of file diff --git a/686/CH8/EX8.2/Ex8_2.sci b/686/CH8/EX8.2/Ex8_2.sci new file mode 100755 index 000000000..ee141bb1c --- /dev/null +++ b/686/CH8/EX8.2/Ex8_2.sci @@ -0,0 +1,23 @@ +clc();
+clear;
+
+// To find the extent of heating of water and heat transfer
+
+d = 0.24/12; // Diameter of tubes in ft
+l = 24/12; // Length of tubes in ft
+v = 3; // velocity of cooling water in ft/sec
+T = 140; // Temperature of cooling water in F
+n = 0.514*10^-5; // Kinematic viscosity in ft^2/sec
+Pr = 3.02; // Prandtls number
+k = 0.376; // Thermal conductivity in Btu/hr-ft-F
+Re = d*v/n; // Reynolds number
+A = 1.5; // Experimental constant
+// Turbulent flow
+// Greater part of the flow is developed , A=1.5 from the table
+
+St = 0.0384*(v*d/n)^-(1/4)/(1+A*(v*d/n)^-(1/8)*(Pr-1)); // Strantons number
+Nu = Re*Pr*St; // Nusselt number
+h = Nu*k/d; // Heat transfer coefficient
+
+printf("The heat transfer coefficient of heating of waterr is %d Btu/hr-ft^2-F",h);
+
diff --git a/686/CH8/EX8.3/Ex8_3.sci b/686/CH8/EX8.3/Ex8_3.sci new file mode 100755 index 000000000..9f231d7a6 --- /dev/null +++ b/686/CH8/EX8.3/Ex8_3.sci @@ -0,0 +1,28 @@ +clc();
+clear;
+
+// To find the heat transfer coefficient at x = 12 in.
+
+Tp = 176; // Temperature of plate in F
+Ta = 68; // Tempearture of air stream in F
+Tm = (Tp+Ta)/2; // Maen temperature in F
+u = 30; // Velocity in fps
+n = 19.45*10^-5; // Dynamic visosity in ft^2/sec
+v = 30; // Velocity in fps
+Pr = 0.703; // Prandtls number
+x = 12/12; // distance in ft
+k = 0.0162; // Thermal conductivity in Btu/hr-ft^2-F
+Re = v*x/n; // Reynolds number
+// The boundary layer must be laminar or turbulent
+
+St = 0.0296*(Re)^-(1/5)/(1+1.75*0.87*(Re)^-(1/10)*(Pr-1)); // Strantons number
+Nu = Re*Pr*St; // Nusselt number
+h = Nu*k/x; // Heat transfer coefficient
+
+printf("The heat transfer coefficient of heating of water for laminar is %.2f Btu/hr-ft^2-F",h)
+
+// If the flow is laminar
+Nu1 = 0.332*Re^(1/2)*Pr^(1/3); // Nusselt number
+h1 = Nu1*k/x; // Heat transfer coefficient
+printf(" \n The heat transfer coefficient for turbilent layer is %.2f Btu/hr",h1);
+
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