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diff --git a/Fluid_Mechanics,Thermodynamics_of_Turbomachinery_by_S.L.Dixon/Chapter7_2hkovpj.ipynb b/Fluid_Mechanics,Thermodynamics_of_Turbomachinery_by_S.L.Dixon/Chapter7_2hkovpj.ipynb new file mode 100644 index 00000000..d65c95f3 --- /dev/null +++ b/Fluid_Mechanics,Thermodynamics_of_Turbomachinery_by_S.L.Dixon/Chapter7_2hkovpj.ipynb @@ -0,0 +1,280 @@ +{
+ "metadata": {
+ "name": "",
+ "signature": "sha256:a61692019b8140a36f6ac02790d0dad90729cb0b28691dad1652c231a1bf0a41"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+ {
+ "cells": [
+ {
+ "cell_type": "heading",
+ "level": 1,
+ "metadata": {},
+ "source": [
+ "Chapter7-Centrifugal Pumps,Fans and Compressors\n"
+ ]
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Ex1-pg216"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "import math\n",
+ "#calculate the\n",
+ "\n",
+ "##function to calculate blade cavitation coefficient\n",
+ "\n",
+ "##given data\n",
+ "Q = 25;##flow rate in dm^3/s\n",
+ "omega = 1450;##rotational speed in rev/min\n",
+ "omega_ss = 3;##max. suction specific speed in rad/sec\n",
+ "r = 0.3;##inlet eye radius ratio\n",
+ "g = 9.81;##in m/s^2\n",
+ "\n",
+ "##Calculations\n",
+ "k = 1.-(r**2);\n",
+ "sigmab = 0.3;##initial guess\n",
+ "d = (sigmab**2)*(1. + sigmab)- (((3.42*k)**2)/(omega_ss**4));\n",
+ "i = 0;\n",
+ "if sigmab>0:\n",
+ "\tsigmab = sigmab - 0.0001;\n",
+ "elif sigmab<0:\n",
+ "\tsigmab = sigmab + 0.0001;\n",
+ "\n",
+ "phi = (sigmab/(2.*(1.+sigmab)))**0.5;\n",
+ "rs1 = ((Q*10**-3.)/(math.pi*k*(omega*math.pi/30.)*phi))**(1./3.);\n",
+ "ds1 = 2.*rs1;\n",
+ "cx1 = phi*(omega*math.pi/30.)*rs1;\n",
+ "Hs = (0.75*sigmab*cx1**2)/(g*phi**2);\n",
+ "\n",
+ "##Results\n",
+ "print'%s %.2f %s'%('(i)The blade cavitation coefficient = ',sigmab,'');\n",
+ "print'%s %.2f %s %.2f %s '%('\\n (ii)The shroud radius at the eye = ',rs1,' m' and '\\n The required diameter of the eye = ',ds1*10**3,'mm');\n",
+ "print'%s %.2f %s'%('\\n (iii)The eye axial velocity = ',cx1,' m/s');\n",
+ "print'%s %.2f %s'%('\\n (iv)The NPSH = ',Hs,' m');\n",
+ "\n",
+ "#asnwer is wrong due to round off error"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "(i)The blade cavitation coefficient = 0.30 \n",
+ "\n",
+ " (ii)The shroud radius at the eye = 0.06 \n",
+ " The required diameter of the eye = 110.70 mm \n",
+ "\n",
+ " (iii)The eye axial velocity = 2.85 m/s\n",
+ "\n",
+ " (iv)The NPSH = 1.62 m\n"
+ ]
+ }
+ ],
+ "prompt_number": 2
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Ex2-pg220"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "import math\n",
+ "#calculate the\n",
+ "\n",
+ "##given data\n",
+ "alpha1 = 30.;##prewhirl in deg\n",
+ "hs = 0.4;##inlet hub-shrub radius ratio\n",
+ "Mmax = 0.9;##max Mach number\n",
+ "Q = 1;##air mass flow in kg/s\n",
+ "p01 = 101.3;##stagnation pressure in kPa\n",
+ "T01 = 288.;##stagnation temperature in K\n",
+ "gamma = 1.4;\n",
+ "Rg = 287.;##in J/(kgK)\n",
+ "\n",
+ "##Calculationsasza\n",
+ "beta1 = 49.4;##in deg\n",
+ "f = 0.4307;\n",
+ "a01 = math.sqrt(gamma*Rg*T01);\n",
+ "rho01 = p01*1000./(Rg*T01);\n",
+ "k = 1-(hs**2);\n",
+ "omega = (math.pi*f*k*rho01*a01**3)**0.5;\n",
+ "N = (omega*60./(2.*math.pi));\n",
+ "rho1 = rho01/(1. + 0.2*(Mmax*math.cos(beta1*math.pi/180.))**2)**2.5;\n",
+ "cx = ((omega**2.)/(math.pi*k*rho1*(math.tan(beta1*math.pi/180.) + math.tan(alpha1*math.pi/180.))**2.))**(1/3.);\n",
+ "rs1 = (1./(math.pi*rho1*cx*k))**0.5;\n",
+ "\n",
+ "ds1 = 2.*rs1;\n",
+ "U = omega*rs1;\n",
+ "\n",
+ "##Results\n",
+ "print'%s %.2f %s %.2f %s '%('(i)The rotational speed of the impeller = ',omega,' rad/s'and 'N = ',N,' rev/min.');\n",
+ "print'%s %.2f %s %.2f %s '%('\\n (ii)The inlet static density downstream of the guide vanes at the shroud = ',rho1,' kg/m^3.'and'\\n The axial velocity = ',cx,' m/s.');\n",
+ "print'%s %.2f %s %.2f %s '%('\\n (iii)The inducer tip diameter = ',ds1*100,' cm'and '\\n U = ',U,' m/s.');\n",
+ "\n",
+ "##there are small errors in the answers given in textbook\n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "(i)The rotational speed of the impeller = 7404.94 N = 70711.94 rev/min. \n",
+ "\n",
+ " (ii)The inlet static density downstream of the guide vanes at the shroud = 1.04 \n",
+ " The axial velocity = 187.38 m/s. \n",
+ "\n",
+ " (iii)The inducer tip diameter = 8.83 \n",
+ " U = 326.81 m/s. \n"
+ ]
+ }
+ ],
+ "prompt_number": 3
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Ex3-pg228"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "import math\n",
+ "#calculate the\n",
+ "\n",
+ "##given data\n",
+ "Q = 0.1;##in m^3/s\n",
+ "N = 1200.;##rotational speed in rev/min\n",
+ "beta2_ = 50.;##in deg\n",
+ "D = 0.4;##impeller external diameter in m\n",
+ "d = 0.2;##impeller internal diameter in m\n",
+ "b2 = 31.7;##axial width in mm\n",
+ "eff = 0.515;##diffuser efficiency\n",
+ "H = 0.1;##head losses\n",
+ "De = 0.15;##diffuser exit diameter\n",
+ "A = 0.77;\n",
+ "B = 1.;\n",
+ "g = 9.81;\n",
+ "\n",
+ "##Calculations\n",
+ "U2 = math.pi*N*D/60.;\n",
+ "cr2 = Q/(math.pi*D*b2/1000.);\n",
+ "sigmaB = (A - H*math.tan(beta2_*math.pi/180.))/(B - H*math.tan(beta2_*math.pi/180.));\n",
+ "ctheta2 = sigmaB*U2*(1.-H*math.tan(beta2_*math.pi/180.));\n",
+ "Hi = U2*ctheta2/g;\n",
+ "c2 = math.sqrt(cr2**2 + ctheta2**2);\n",
+ "c3 = 4.*Q/(math.pi*De**2);\n",
+ "HL = 0.1*Hi + 0.485*((c2**2)-(c3**2))/(2.*g) + (c3**2.)/(2.*g);\n",
+ "H = Hi - HL;\n",
+ "eff_hyd = H/Hi;\n",
+ "\n",
+ "##Results\n",
+ "print'%s %.2f %s'%('The slip factor = ',sigmaB,'');\n",
+ "print'%s %.2f %s'%('\\n The manometric head = ',H,' m.');\n",
+ "print'%s %.2f %s'%('\\n The hydraulic efficiency = ',eff_hyd*100,' percentage.');\n",
+ "\n",
+ "##there is a very small error in the answer given in textbook\n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "The slip factor = 0.74 \n",
+ "\n",
+ " The manometric head = 30.11 m.\n",
+ "\n",
+ " The hydraulic efficiency = 71.84 percentage.\n"
+ ]
+ }
+ ],
+ "prompt_number": 4
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Ex4-pg235"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "import math\n",
+ "#calculate the\n",
+ "\n",
+ "##given data\n",
+ "T01 = 22.;##stagnation temperature in degC\n",
+ "Z = 17.;##number of vanes\n",
+ "N = 15000.;##rotational speed in rev/min\n",
+ "r = 4.2;##stagnation pressure ratio between diffuser and impeller\n",
+ "eff_ov = 0.83;##overall efficiency\n",
+ "mdot = 2;##mass flow rate in kg/s\n",
+ "eff_m = 0.97;##mechanical efficiency\n",
+ "rho2 = 2.;##air density at impeller outle in kg/m^3\n",
+ "gamma = 1.4;\n",
+ "R = 0.287;##in kJ/(kg.K)\n",
+ "b2 = 11.;##axial width at the entrance to the diffuser in mm\n",
+ "\n",
+ "##Calculations\n",
+ "Cp = gamma*R*1000./(gamma-1.);\n",
+ "sigmaS = 1 - 2./Z;\n",
+ "U2 = math.sqrt(Cp*(T01+273.)*((r)**((gamma-1.)/gamma) -1.)/(sigmaS*eff_ov));\n",
+ "omega = N*math.pi/30.;\n",
+ "rt = U2/omega;\n",
+ "Wdot_act = mdot*sigmaS*(U2**2)/(eff_m);\n",
+ "cr2 = mdot/(rho2*2.*math.pi*rt*b2/1000.);\n",
+ "ctheta2 = sigmaS*U2;\n",
+ "c2 = math.sqrt(ctheta2**2 +cr2**2);\n",
+ "delW = sigmaS*U2**2;\n",
+ "T2 = T01+273.+(delW - 0.5*c2**2)/Cp;\n",
+ "M2 = c2/math.sqrt(gamma*R*1000.*T2);\n",
+ "\n",
+ "##Results\n",
+ "print'%s %.2f %s'%('Absolute mach number, M2 = ',M2,'');\n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "Absolute mach number, M2 = 1.01 \n"
+ ]
+ }
+ ],
+ "prompt_number": 5
+ }
+ ],
+ "metadata": {}
+ }
+ ]
+}
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