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diff --git a/Introduction_to_Heat_Transfer_by_S._K._Som/Chapter9.ipynb b/Introduction_to_Heat_Transfer_by_S._K._Som/Chapter9.ipynb new file mode 100644 index 00000000..7d76afa3 --- /dev/null +++ b/Introduction_to_Heat_Transfer_by_S._K._Som/Chapter9.ipynb @@ -0,0 +1,727 @@ +{ + "cells": [ + { + "cell_type": "markdown", + "metadata": { + "collapsed": true + }, + "source": [ + "# Chapter 09:Heat transfer in condensation and boiling" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex9.1:pg-392" + ] + }, + { + "cell_type": "code", + "execution_count": 17, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Introduction to heat transfer by S.K.Som, Chapter 9, Example 1\n", + "The properties of condensate(liquid water) are evaluated at the mean film temprature \n", + "The mean film temprature in°C is\n", + "tf= 95\n", + "hfg= 2270000.0\n", + "The average heat transfer coefficient over length L in W/(m**2*K)\n", + "hbar= 0.745\n", + "The rate of heat transfer per unit width in W/m \n", + "Q= 3.772\n", + "The total rate of condensation in kg/(s*m)\n", + "mdotc= 1.66167400881e-06\n", + "We have to check whether the flow is laminar or not \n", + "Reynolds no. is\n", + "Therefore the flow is laminar and hence the use of the equation is justified\n", + "ReL= 0.0221556534508\n" + ] + } + ], + "source": [ + " \n", + " \n", + " \n", + " \n", + "import math\n", + " \n", + "print\"Introduction to heat transfer by S.K.Som, Chapter 9, Example 1\"\n", + "#A vertical cooling fin, Approximately a flat plate length,(L)=0.4m high is exposed to saturated steam(temprature,Tg=100°C) at atmospheric pressure.\n", + "L=0.4;\n", + "Tg=100;\n", + "#The fin is maintained at temprature,Tw=90°C by cooling water.\n", + "Tw=90;\n", + "print\"The properties of condensate(liquid water) are evaluated at the mean film temprature \"\n", + "#tf is mean film temprature\n", + "print\"The mean film temprature in°C is\"\n", + "tf=(Tg+Tw)/2\n", + "print\"tf=\",tf\n", + "#The properties of condensate are density(rho=962kg/m**3),conductivity(k=0.677W/(m*K)),viscosity(mu=3*10**-4 kg/(m*s))\n", + "rho=962;\n", + "k=0.677;\n", + "mu=3*10**-4;\n", + "#The value rhov=0.598kg/m**3 and hfg=2.27*10**6J/kg at 100°C are found from steam table\n", + "#g is acceleration due to gravity =9.81m/s**2\n", + "g=9.81;\n", + "rhov=0.598;#rhov is vapour density\n", + "hfg=2.27*10**6;#hfg is enthalpy of vaporisation\n", + "print\"hfg=\",hfg\n", + "#The average heat transfer coefficient over length L is hbarL=0.943*((rho*(rho-rhov)*g*h*L**3)/(mu*k*(Tg-Tw)))**(1/4)\n", + "print\"The average heat transfer coefficient over length L in W/(m**2*K)\"\n", + "hbarL=0.943*((rho*(rho-rhov)*g*hfg*k**3)/(mu*L*(Tg-Tw)))**(1/4)\n", + "print\"hbar=\",hbar\n", + "#The rate of heat transfer per unit width is Q=hbarL*L*(Tg-Tw)\n", + "print\"The rate of heat transfer per unit width in W/m \"\n", + "Q=hbarL*L*(Tg-Tw)\n", + "print\"Q=\",Q\n", + "#The rate of condensation is given by mdotc=(Q/hfg)\n", + "print\"The total rate of condensation in kg/(s*m)\"\n", + "mdotc=(Q/hfg)\n", + "print\"mdotc=\",mdotc\n", + "print\"We have to check whether the flow is laminar or not \"\n", + "#Reynolds no is given by ReL=(4*mdotc)/(mu)\n", + "print\"Reynolds no. is\"\n", + "ReL=(4*mdotc)/(mu)\n", + "print\"Therefore the flow is laminar and hence the use of the equation is justified\"\n", + "print\"ReL=\",ReL\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex9.2:pg-393" + ] + }, + { + "cell_type": "code", + "execution_count": 16, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Introduction to heat transfer by S.K.Som, Chapter 9, Example 2\n", + "The mean film temprature in°C is\n", + "tf= 95\n", + "hfg= 2270000.0\n", + "The average heat transfer coefficient in W/(m**2*K)\n", + "hbar= 0.745\n", + "The total rate of condensation in kg/s\n", + "Check for reynolds no.\n", + "mdotc= 1.54657700017e-06\n", + "Reynolds number is\n", + "Re= 0.00343683777816\n" + ] + } + ], + "source": [ + " \n", + " \n", + " \n", + " \n", + "import math\n", + " \n", + "print\"Introduction to heat transfer by S.K.Som, Chapter 9, Example 2\"\n", + "#Steam is condensed at temprature(Tg=100°C) on the outer surafce of a horizontal tube of length(L=3m) and diameter(d)=50mm or .05m\n", + "Tg=100;\n", + "L=3;\n", + "D=0.05;\n", + "#The Tube surface is maintained at temprature,Tw=90°C \n", + "Tw=90;\n", + "#tf is mean film temprature\n", + "print\"The mean film temprature in°C is\"\n", + "tf=(Tg+Tw)/2\n", + "print\"tf=\",tf\n", + "#The properties of condensate are density(rho=962kg/m**3),conductivity(k=0.677W/(m*K)),viscosity(mu=3*10**-4 kg/(m*s))\n", + "rho=962;\n", + "k=0.677;\n", + "mu=3*10**-4;\n", + "#The value rhov=0.598kg/m**3 and hfg=2.27*10**6J/kg at 100°C are found from steam table\n", + "#g is acceleration due to gravity =9.81m/s**2\n", + "g=9.81;\n", + "rhov=0.598;#vapour density\n", + "hfg=2.27*10**6;#enthalpy of vaporisation\n", + "print\"hfg=\",hfg\n", + "#The average heat transfer coefficient hbar=0.745*((rho*(rho-rhov)*g*hfg*k**3)/(mu*D*(Tg-Tw)))**(1/4)\n", + "print\"The average heat transfer coefficient in W/(m**2*K)\"\n", + "hbar=0.745*((rho*(rho-rhov)*g*hfg*k**3)/(mu*D*(Tg-Tw)))**(1/4)\n", + "print\"hbar=\",hbar\n", + "#The rate of condensation is given by mdotc=(hbar*(pi*D*L)*(Tg-Tw))/hfg\n", + "print\"The total rate of condensation in kg/s\"\n", + "mdotc=(hbar*(math.pi*D*L)*(Tg-Tw))/hfg\n", + "print\"Check for reynolds no.\"\n", + "print\"mdotc=\",mdotc\n", + "#For a horizontal tube having length,L,perimeter is P=2L\n", + "P=2*L;\n", + "#Re is reynolds number\n", + "print\"Reynolds number is\"\n", + "Re=(4*mdotc)/(mu*P)\n", + "print\"Re=\",Re\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex9.3:pg-394" + ] + }, + { + "cell_type": "code", + "execution_count": 13, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Introduction to heat transfer by S.K.Som, Chapter 9, Example 3\n", + "The mean film temprature in°C is\n", + "tf= 80\n", + "The average heat transfer coefficient over length L in W/(m**2*K)\n", + "hbar= 0.943\n", + "The rate of heat transfer in kW \n", + "Q= 0.016974\n", + "(b)The film thickness at the trailing edges in m is\n", + "delta= 1.0\n", + "The total rate of condensation in kg/s\n", + "mdotc= 7.47753303965e-06\n", + "Hence the average flow velocity at the trailing edge in m/s is\n", + "v= 2.56431174199e-08\n" + ] + } + ], + "source": [ + " \n", + " \n", + " \n", + " \n", + "import math\n", + " \n", + "print\"Introduction to heat transfer by S.K.Som, Chapter 9, Example 3\"\n", + "#A vertical plate having length,(L)=1.5m is maintained at temprature(Tw) of 60°C in the presence of saturated steam(temprature,Tg=100°C) at atmospheric pressure.\n", + "L=1.5;\n", + "Tg=100;\n", + "Tw=60;\n", + "#Consider the width of plate to be (B)=0.3m\n", + "B=0.3;\n", + "#tf is the mean film temprature\n", + "print\"The mean film temprature in°C is\"\n", + "tf=(Tg+Tw)/2\n", + "print\"tf=\",tf\n", + "#The relevant properties are desity(rho=972kg/m**3),conductivity(k=0.670W/(m*K)),viscosity(mu=3.54*10**-4 kg/(m*s))\n", + "#specific heat(cp=4.2J/(kg*K)),vapur density(rhov(100°C)=0.598k/m**3),Enthalpy of vaporisation(hfg(100°C)=2.27*10**6J/kg)\n", + "#g is acceleration due to gravity =9.81m/s**2\n", + "g=9.81;\n", + "rho=972;\n", + "k=0.670;\n", + "mu=3.54*10**-4;\n", + "cp=4.2;\n", + "rhov=0.598;\n", + "hfg=2.27*10**6;\n", + "#The average heat transfer coefficient over length L is hbar=0.943*((rho*(rho-rhov)*g*h*L**3)/(mu*k*(Tg-Tw)))**(1/4)\n", + "print\"The average heat transfer coefficient over length L in W/(m**2*K)\"\n", + "hbar=0.943*((rho*(rho-rhov)*g*hfg*k**3)/(mu*L*(Tg-Tw)))**(1/4)\n", + "print\"hbar=\",hbar\n", + "#The rate of heat transfer Q=hbarL*A*(Tg-Tw)\n", + "#Area(A)=L*B\n", + "A=L*B;\n", + "print\"The rate of heat transfer in kW \"\n", + "Q=(hbar*A*(Tg-Tw))/1000\n", + "print\"Q=\",Q\n", + "#The film thickness at the trailing edges is found out by delta=((4*mu*k*x*(Tg-Tw))/(g*hfg*rho*(rho-rhov)))**(1/4)\n", + "print\"(b)The film thickness at the trailing edges in m is\"\n", + "#at trailing edges x=1.5m\n", + "x=1.5;\n", + "delta=((4*mu*k*x*(Tg-Tw))/(g*hfg*rho*(rho-rhov)))**(1/4)\n", + "print\"delta=\",delta\n", + "#The rate of condensation is given by mdotc=(Q/hfg)\n", + "print\"The total rate of condensation in kg/s\"\n", + "mdotc=((Q*1000)/hfg)\n", + "print\"mdotc=\",mdotc\n", + "#v is the average flow velocity\n", + "print\"Hence the average flow velocity at the trailing edge in m/s is\"\n", + "v=(mdotc)/(rho*delta*B)\n", + "print\"v=\",v\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex9.4:pg-396" + ] + }, + { + "cell_type": "code", + "execution_count": 11, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Introduction to heat transfer by S.K.Som, Chapter 9, Example 4\n", + "The mean film temprature in°C is\n", + "tf= 30\n", + " Modified enthalpy in J/kg is\n", + "hfgdash= 131330.0\n", + "The average heat transfer coefficient over length L in W/(m**2*K)\n", + "hbar= 0.555\n", + "The total rate of condensation in kg/hr\n", + "mdotc= 0.00716923260703\n" + ] + } + ], + "source": [ + " \n", + " \n", + " \n", + " \n", + "import math\n", + " \n", + "print\"Introduction to heat transfer by S.K.Som, Chapter 9, Example 4\"\n", + "#Saturated freon-012 at Temprature(Tg)=35°C is condensed horizontal tube of diameter(D)=15mm or.015m at a lower vapour velocity.\n", + "#length,L=1m,Since per meter of tube is considered.\n", + "L=1;\n", + "Tg=35;\n", + "D=0.015;\n", + "#The tube wall is maintained at temprature(Tw)=25°C\n", + "Tw=25;\n", + "#For freon-12 at 35°C,enthalpy of vaporisation(hfg=131.33kJ/kg) and vapour density(rhov=42.68kg/m**3)\n", + "hfg=131.33*10**3;\n", + "rhov=42.68;\n", + "#tf is mean film temprature\n", + "print\"The mean film temprature in°C is\"\n", + "tf=(Tg+Tw)/2\n", + "print\"tf=\",tf\n", + "#The relevant properties at 30°C are density(rho=1.29*10**3kg/m**3),conductivity(k=0.071W/(mK)),viscosity(mu=2.50*10**-4kg/(m*s)),specific heat(cp=983J/(kg*°C))\n", + "rho=1.29*10**3;\n", + "k=0.071;\n", + "mu=2.50*10**-4;\n", + "cp=983;\n", + "#g is acceleration due to gravity =9.81m/s**2\n", + "g=9.81;\n", + "#we found the modified enthalpy by using following equation hfgdash=hfg+(3/8)*cp*(Tg-Tw)\n", + "print\" Modified enthalpy in J/kg is\"\n", + "hfgdash=hfg+((3/8)*cp*(Tg-Tw))\n", + "print\"hfgdash=\",hfgdash\n", + "#The average heat transfer coefficient over length L is hbar=0.555*((rho*(rho-rhov)*g*hfgdash*k**3)/(mu*D*(Tg-Tw)))**(1/4)\n", + "print\"The average heat transfer coefficient over length L in W/(m**2*K)\"\n", + "hbar=0.555*((rho*(rho-rhov)*g*hfgdash*k**3)/(mu*D*(Tg-Tw)))**(1/4)\n", + "print\"hbar=\",hbar\n", + "#The rate of condensation is given by mdotc=(hbar*(pi*D*L)*(Tg-Tw))/hfg\n", + "print\"The total rate of condensation in kg/hr\"\n", + "mdotc=((hbar*(math.pi*D*L)*(Tg-Tw))/hfg)*3600\n", + "print\"mdotc=\",mdotc\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex9.5:pg-397" + ] + }, + { + "cell_type": "code", + "execution_count": 7, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Introduction to heat transfer by S.K.Som, Chapter 9, Example 5\n", + "Heat transfer coefficient in W/m**2 is\n", + "h= 105042.262441\n" + ] + } + ], + "source": [ + " \n", + " \n", + " \n", + " \n", + "import math\n", + " \n", + "print\"Introduction to heat transfer by S.K.Som, Chapter 9, Example 5\"\n", + "#A nickel wire of length(L)=0.1m,Diameter(D)=1mm or .001m \n", + "#Submerged horizontally in water at pressure=1 atm(101kPa) requires current,I=150A at voltage ,E=2.2V to maintain wire at temprature(T1)=110°C\n", + "L=0.1;\n", + "T1=110;\n", + "D=0.001;\n", + "I=150;\n", + "E=2.2;\n", + "#Area(A)=(math.pi*D*L)\n", + "A=math.pi*D*L;\n", + "#The saturation temprature of water at one atmospheric pressure(101kPa) is T2=100°C.\n", + "T2=100;\n", + "#We can write from energy balance E*I=h*A*(T1-T2),we can find heat transfer coefficient from it.\n", + "#h is heat transfer coefficient\n", + "print\"Heat transfer coefficient in W/m**2 is\"\n", + "h=(E*I)/(A*(T1-T2))\n", + "print\"h=\",h\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex9.6:pg-398" + ] + }, + { + "cell_type": "code", + "execution_count": 18, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Introduction to heat transfer by S.K.Som, Chapter 9, Example 6\n", + "Critical Heat flux in W/m**2 is\n", + "qc= 202044.0\n", + "The burn out voltage in Volts is \n", + "E= 1.90421983831\n" + ] + } + ], + "source": [ + " \n", + " \n", + " \n", + " \n", + "import math\n", + " \n", + "print\"Introduction to heat transfer by S.K.Som, Chapter 9, Example 6\"\n", + "#In a laboratory experiment,A current(I)=100A burns out a nickel wire having Diameter(D)=1mm or 0.001mm,length(L)=0.3m\n", + "I=100;\n", + "D=.001;\n", + "L=0.3;\n", + "#It is submerged horizontally in water at one atmospheric pressure.\n", + "#For saturated water at one atmospheric pressure,density(rhol=960kg/m**3),vapour density(rhov=0.60kg/m**3),enthalpy of vaporisation(hfg=2.26*10**6J/kg),surface tension(sigma=0.055N/m).\n", + "rhol=960;\n", + "rhov=0.60;\n", + "hfg=2.26*10**6;\n", + "sigma=0.055;\n", + "#Area(A)=(pi*D*L)\n", + "A=math.pi*D*L;\n", + "#g is acceleration due to gravity =9.81m/s**2\n", + "g=9.81;\n", + "#The wire is burnt out when heat reaches its peak\n", + "#We use following expression to determine critical heat flux qc=0.149*hfg*rhov*((sigma*g*(rhol-rhov))/rhov**2)**(1/4)*((rhol+rhov)/rhol)**(1/2) \n", + "print\"Critical Heat flux in W/m**2 is\"\n", + "qc=0.149*hfg*rhov*((sigma*g*(rhol-rhov))/rhov**2)**(1/4)*((rhol+rhov)/rhol)**(1/2) \n", + "print\"qc=\",qc\n", + "#From the energy balance E*I=qc*A\n", + "#E is the burn out voltage\n", + "print\"The burn out voltage in Volts is \"\n", + "E=(qc*A)/I\n", + "print\"E=\",E\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex9.7:pg-399" + ] + }, + { + "cell_type": "code", + "execution_count": 19, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Introduction to heat transfer by S.K.Som, Chapter 9, Example 7\n", + "Heat flux q in W/m**2 is\n", + "The peak heat flux for water at one atmospheric pressure is qc=1.24*10**6(found in example 9.6).Since q<qc,The regime of boiling is nucleate.\n", + "q= 3636.07255495\n" + ] + } + ], + "source": [ + " \n", + " \n", + " \n", + " \n", + "import math\n", + " \n", + "print\"Introduction to heat transfer by S.K.Som, Chapter 9, Example 7\"\n", + "#A heated nickel plate at temprature (T1)=110°C is submereged in water at one atmospheric pressure.\n", + "T1=110;\n", + "#For nucleate boiling coefficient(csf=0.006) and n=1\n", + "csf=0.006;\n", + "n=1;\n", + "#For saturated water at one atmospheric pressure,density of liquid(rhol=960kg/m**3),vapour density(rhov=0.60kg/m**3)\n", + "#enthalpy of vaporisation(hfg=2.26*10**6J/kg),surface tension(sigma=0.055N/m),saturation temprature(T2)=100°C\n", + "T2=100;\n", + "rhol=960;\n", + "rhov=0.60;\n", + "hfg=2.26*10**6;\n", + "sigma=0.055;\n", + "#g is acceleration due to gravity =9.81m/s**2\n", + "g=9.81;\n", + "#We take specific heat of liquid(cpl=4.216kJ/(kg*K)),prandtl number of liquid(Prl=1.74),viscosity of liquid(mul=2.82*10**-4kg/(m*s))\n", + "cpl=4.216*10**3;\n", + "Prl=1.74;\n", + "mul=2.82*10**-4;\n", + "#The heat flux q is given by expression q=(mul*hfg)*(((rhol-rhov)*g)/sigma)**(1/2)*((cpl*(T1-T2))*(csf*hfg*prl**n))**3 \n", + "print\"Heat flux q in W/m**2 is\"\n", + "q=(mul*hfg)*(((rhol-rhov)*g)/sigma)**(1/2)*((cpl*(T1-T2))/(csf*hfg*Prl**n))**3 \n", + "print\"The peak heat flux for water at one atmospheric pressure is qc=1.24*10**6(found in example 9.6).Since q<qc,The regime of boiling is nucleate.\"\n", + "print\"q=\",q\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex9.8:pg-401" + ] + }, + { + "cell_type": "code", + "execution_count": 1, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Introduction to heat transfer by S.K.Som, Chapter 9, Example 8\n", + "The heat flux in W/m**2 is\n", + "q= 750000.0\n", + "The surface temprature in °C is\n", + "Tw= 120.0\n", + "The value of the coefficient csf is \n", + "csf= 0.0151329179422\n" + ] + } + ], + "source": [ + " \n", + " \n", + " \n", + " \n", + "import math\n", + " \n", + "print\"Introduction to heat transfer by S.K.Som, Chapter 9, Example 8\"\n", + "#A Copper bar whose one end is exposed to boiling water while the other end is encapsulated by an electric heater.\n", + "#Thermocouples are inserted in the bar to measure the tempratures at two locations A and b at distances xA=10mm and xB=30mm from the surface.\n", + "xA=.010;\n", + "xB=.030;\n", + "#Under steady condition nucleate boiling is maintained in saturated water at atmospheric pressure and the tempratures are TA=140°C and TB=180°C,n=1\n", + "TA=140;\n", + "TB=180;\n", + "n=1;\n", + "#The values of relevant properties of water and other parameters are \n", + "#density of liquid(rhol=960kg/m**3),vapour density(rhov=0.60kg/m**3),specific heat of liquid(cpl=4.216 kJ/(kg*K))\n", + "#enthalpy of vaporisation(hfg=2.26*106J/kg),prandtl number of liquiid(Prl=1.74),viscosity of liquid(mul=2.82*10**-4kg/(m*s)),surface tension(sigma1=0.055N/m).\n", + "rhol=960;\n", + "rhov=0.60;\n", + "cpl=4.216*10**3;\n", + "hfg=2.26*10**6;\n", + "Prl=1.74;\n", + "mul=2.82*10**-4;\n", + "sigma1=0.055;\n", + "#We have to know the value of heat flux(q) and the surface temprature(Tw).\n", + "#Since we know the tempratures at location A and B,The heat flux q is determined by fourier law of heat conduction in the bar at steady-state as\n", + "#q=k*((TB-TA)/(xB-xA))\n", + "#We take for copper conductivity,k=375W/(m*K)\n", + "k=375;\n", + "print\"The heat flux in W/m**2 is\"\n", + "q=k*((TB-TA)/(xB-xA))\n", + "print\"q=\",q\n", + "#g is acceleration due to gravity =9.81m/s**2\n", + "g=9.81;\n", + "#The surface temprature is given by Tw=TA-((TB-TA)/(xB-xA))*xA\n", + "print\"The surface temprature in °C is\"\n", + "Tw=TA-((TB-TA)/(xB-xA))*xA\n", + "print\"Tw=\",Tw\n", + "#Temprature,T=100°C,since copper bar is exposed to boiling water. \n", + "T=100;\n", + "#Now we use following equation to determine csf,q=(mul*hfg)*(((rhol-rhov)*g)/sigma1)**(1/2)*((cpl*(Tw-T))/(csf*hfg*Prl**n))**3 \n", + "#Manipulating above equation to find csf we get csf=((cpl*(Tw-T))/(((q/((mul*hfg)*(((rhol-rhov)*g)/sigma1)**(1/2))**(1/3))*hfg*Prl**n))\n", + "print\"The value of the coefficient csf is \"\n", + "csf=((cpl*(Tw-T))/(((q/((mul*hfg)*(((rhol-rhov)*g)/sigma1)**(1.0/2)))**(1.0/3))*hfg*Prl**n))#[NOTE:The answer in the book is incorrect.(Calcultion mistake)]\n", + "print\"csf=\",csf\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n", + "\n" + ] + } + ], + "metadata": { + "kernelspec": { + "display_name": "Python 2", + "language": "python", + "name": "python2" + }, + "language_info": { + "codemirror_mode": { + "name": "ipython", + "version": 2 + }, + "file_extension": ".py", + "mimetype": "text/x-python", + "name": "python", + "nbconvert_exporter": "python", + "pygments_lexer": "ipython2", + "version": "2.7.11" + } + }, + "nbformat": 4, + "nbformat_minor": 0 +} |