{ "metadata": { "name": "", "signature": "sha256:0b5a0b6f6c6e071c339201ca91727b19aa4afe9cff0ebf23f723c14d23de7be3" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 9 : Fluid Flow in Pipes" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.1 Page No : 281" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\n", "# variables\t\t\n", "d = 6.;\t \t#inches\n", "v = 15.;\t\t#fps\n", "l = 100.;\t\t#ft\n", "h_L = 17.5;\t\t#ft\n", "\n", "# calculations \n", "f = round(h_L*(d/(12*l))*(2*32.2/v**2),3);\n", "V_f = v*math.sqrt(f/8.);\n", "\n", "# results \n", "print 'The friction velocity = %.2f fps'%(V_f);\n", "\n", "#incorrect answer in textbook" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "0.025\n", "The friction velocity = 0.84 fps\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.2 Page No : 285" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\t\t\n", "# variables\n", "T = 100.;\t\t# degreeF\n", "d = 3.;\t\t # inches\n", "Re = 80000.;\t# Reynolds number\n", "e = 0.006;\t\t# inches\n", "l = 1000.;\t\t#feet\n", "f1 = 0.021;\t\t#friction factor\n", "nu = 0.729*10**-5;\t\t# sqft/sec\n", "\n", "# calculations \n", "V = Re*nu/0.25;\n", "h_L1 = f1*(l/0.25)*(V**2 /(2*32.2));\n", "f = 0.316/Re**0.25;\n", "h_L = (f/f1)*h_L1;\n", "\n", "# results \n", "print 'Head loss expected = %.1f ft and head loss expected if the pipe were smooth = %.2f ft'%(h_L1,h_L);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Head loss expected = 7.1 ft and head loss expected if the pipe were smooth = 6.35 ft\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.3 Page No : 288" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\t\t\n", "# variables\n", "T = 100.;\t\t#degreeF\n", "d = 3.;\t\t # inches\n", "Re = 80000.;\t# Reynolds number\n", "e = 0.006;\t\t#inches\n", "l = 1000.;\t\t#ft\n", "f = 0.0255;\t\t#friction factor\n", "V = 2.33;\t\t#fps\n", "\n", "# calculations \n", "h_L = f*(l/0.25)*(V**2 /(2*32.2));\n", "\n", "# results \n", "print 'Head loss expected = %.1f ft'%(h_L);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Head loss expected = 8.6 ft\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.4 Page No : 290" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\t\t\n", "# variables\n", "Q = 100.;\t\t#gallons per minute\n", "sg = 0.90;\n", "nu = 0.0012;\t# lb-sec/sqft\n", "d = 3.;\t\t # in\n", "l = 1000.;\t\t#ft\n", "r = 1.;\t\t #in\n", "V = 4.53;\t\t#fps\n", "\n", "# calculations \n", "Re = V*(d/12)*sg*1.935/nu;\n", "h_L = (64/Re)*(12*l/d)*(V**2 /(2*32.2));\n", "v = 2*V*(1 - (2/d)**2);\n", "tau = 62.4*sg*h_L/(2*l*12);\n", "\n", "# results \n", "print 'v = %.2f fps, h_L = %.1f ft of oil and tau = %.3f psf'%(v,h_L,tau);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "v = 5.03 fps, h_L = 49.6 ft of oil and tau = 0.116 psf\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.5 pageno : 293" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "# variables\n", "# assume\n", "v_vc = 0.80 \n", "V = 8.35 #fps\n", "R = 737000\n", "f = 0.019 # from fig.\n", "\n", "# calculations\n", "V_Vc = 1./(1+ 4.07* math.sqrt(f/8))\n", "Q = math.pi * V/4\n", "# results\n", "print \"V/Vc = %.3f\"%V_Vc\n", "print \"Q = %.2f cfs\"%Q" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "V/Vc = 0.834\n", "Q = 6.56 cfs\n" ] } ], "prompt_number": 14 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.6 Page No : 295" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\t\t\n", "# variables\n", "Q = 90.;\t\t# gallons per minute\n", "T = 68.;\t\t#degreeF\n", "d = 3.;\t\t # in\n", "l = 3000.;\t\t#ft\n", "r = 1.;\t\t # in\n", "f = 0.018;\n", "\n", "# calculations \n", "V = Q/(60*7.48*0.25*math.pi*(d/12)**2);\n", "Re = V*(d/12)*1.935/(0.000021);\n", "h_L = f*(l/0.25)*(V**2 /(2*32.2));\n", "tau_0 = f*1.935*V**2 /8;\n", "tau1 = 2*tau_0/d;\n", "v_c = V*(1+4.07*math.sqrt(f/8));\n", "v_ = math.sqrt(tau_0/1.935);\n", "v1 = v_*(5.50+5.75*math.log10(v_*(r/(2*12))/0.00001085));\n", "v1_ = v_c-v_*5.75*math.log10(0.5*d/(r/2));\n", "delta = d*32.8/(Re*math.sqrt(f));\n", "\n", "# results \n", "print 'Head lost = %.1f ft of water \\\n", "\\nWall shear stress = %.3f psf \\\n", "\\nthe center velocity = %.2f fps \\\n", "\\nshearing stress = %.3f psf \\\n", "\\nv1 = %.2f fps \\\n", "\\ndelta = %.4f in.'%(h_L,tau_0,v_c,tau1,v1_,delta);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Head lost = 56.0 ft of water \n", "Wall shear stress = 0.073 psf \n", "the center velocity = 4.87 fps \n", "shearing stress = 0.048 psf \n", "v1 = 4.34 fps \n", "delta = 0.0078 in.\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.7 Page No : 298" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\t\t\n", "# variables\n", "d = 12.;\t\t# in\n", "v = 10.;\t\t#fps\n", "e = 2.;\t\t #in\n", "k = 0.002;\t\t#relative roughness\n", "l = 1000.;\t\t#ft\n", "\n", "# calculations \n", "f = (1/(1.14+2*math.log10(1/k)))**2;\n", "v_c = v*(1+4.07*math.sqrt(f/8));\n", "tau_0 = f*1.935*v**2 /8;\n", "v2 = v_c - tau_0*5.75*math.log10(0.5*d/e);\n", "v2_ = 8.48*tau_0 + tau_0*5.75*math.log10(e/(12*k));\n", "h_L = f*(l)*v**2 /(2*32.2); \n", "\n", "# results \n", "print 'f = %.4f, v_c = %.2f fps, v2 = %.1f fps and h_L = %.1f ft of water'%(f,v_c,v2_,h_L);\n", "\n", "#there are small errors in the answer given in textbook" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "f = 0.0234, v_c = 12.20 fps, v2 = 11.0 fps and h_L = 36.3 ft of water\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.8 Page No : 300" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\t\t\n", "# variables\n", "V = 4.08;\t\t # fps\n", "Re = 93800.;\t\t#Reynolds number\n", "r = 1.;\t\t#in\n", "m = 1./7;\n", "R = 3.;\t\t#in\n", "\n", "# calculations \n", "f = 0.316/(Re**0.25);\n", "v_c = V/(2/((m+1)*(m+2)));\n", "v1 = v_c*(r/R)**(1./7);\n", "tau_0 = f*1.935*V**2 /8;\n", "\n", "# results \n", "print 'f = %.3f, v_c = %.2f fps, v1 = %.2f fps and wall shear = %.3f ps'%(f,v_c,v1,tau_0);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "f = 0.018, v_c = 5.00 fps, v1 = 4.27 fps and wall shear = 0.073 ps\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.9 Page No : 302" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\t\t\n", "# variables\n", "p = 14.7;\t\t#psia\n", "T = 60.;\t\t# degreeF\n", "l = 2000.;\t\t#ft\n", "b = 18.;\t\t#in\n", "h = 12.;\t\t# in\n", "v = 10.;\t\t# fps\n", "\n", "# calculations \n", "R_h = (b*h)/(2*12*(b+h));\n", "Re = v*4*R_h*0.0763/(32.2*0.000000375);\n", "f = 0.019;\n", "h_L = f*(l/(4*R_h))*v**2 /(2*32.2);\n", "del_p = 0.0763*h_L;\n", "\n", "# results \n", "print 'loss of head = %.1f ft of air and the pressure drop = %.2f psf = %.3f psi'%(h_L,del_p,del_p*0.0069);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "loss of head = 49.2 ft of air and the pressure drop = 3.75 psf = 0.026 psi\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.10 Page No : 305" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\n", "# variables\n", "Q = 90.;\t\t#gpm\n", "d = 3.;\t\t#in\n", "l = 3000.;\t\t#ft\n", "\n", "# calculations \n", "V = Q/(60*7.48*0.25*math.pi*(d/12)**2);\n", "R_h = (d/12)/4;\n", "C_hw = 140;\n", "S = (V/(1.318*140*R_h**0.63))**(1/0.54);\n", "h_L = S*l;\n", "\n", "# results \n", "print 'The loss of head = %.1f ft of water'%(h_L);\n", "\n", "\t\t" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The loss of head = 65.7 ft of water\n" ] } ], "prompt_number": 11 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.11 Page No : 307" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from sympy import *\n", "import math \n", "\n", "# variables\n", "G = 40.;\t\t# lb/min\n", "d = 3.;\t\t# in\n", "T = 100.;\t\t# degreeF\n", "p = 50.;\t\t# psia\n", "l = 2000.;\t\t#ft\n", "\n", "# calculations \n", "Re = ((G/60)*(d/12))/(0.0491*32.2*4*10**-7);\n", "f = 0.015;\n", "gam1 = p*(144/(53.3*(T+460)));\n", "V1 = (G/60)/(gam1*0.0491);\n", "a = math.sqrt(1.4*32.2*53.3*(T+460));\n", "M1 = V1/a;\n", "M2_limit = math.sqrt(1/1.4);\n", "l = (((1-(M1/M2_limit)**2)/(1.4*M1**2)) - 2*math.log(M2_limit/M1))*(0.25/0.015);\n", "p2 = 38.9;\t\t#psia, from trial and error method \n", "#p2 = Symbol('p2')\n", "#ans = solve((G/60)**2 * 53.3*560/(32.2 * 0.0491**2) * (2*log(p/p2) + gam1*l/0.25) - (144**2 * (p**2 - p2**2)))\n", "\n", "# results \n", "print 'p2 = %.1f psia'%(p2);\n", "\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "p2 = 38.9 psia\n" ] } ], "prompt_number": 11 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.12 Page No : 312" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\t\t\n", "# variables\n", "d = 12.;\t\t# in\n", "D = 24.;\t\t#in\n", "theta = 20.;\t\t#degrees\n", "G = 10.;\t\t#cfs\n", "p = 20.;\t\t#psi\n", "\n", "# calculations \n", "V12 = G/(0.25*math.pi);\n", "V24 = V12/4;\n", "K_L = 0.43;\n", "p24 = ((p*144/62.4) + (V12**2 /(2*32.2)) - ((V24**2)/(2*32.2)) - K_L*(V12-V24)**2 /(2*32.2))/2.314;\n", "\n", "# results \n", "print 'Pressure in the larger pipe = %.1f psi'%(p24);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Pressure in the larger pipe = 20.7 psi\n" ] } ], "prompt_number": 13 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.13 Page No : 322" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\n", "# variables\n", "d = 12.;\t\t# in\n", "l = 1000.;\t\t#ft\n", "h1 = 200.;\t\t#elevation\n", "h2 = 250.;\t\t#elevation\n", "T = 50.;\t\t#degreeF\n", "f1 = 0.030;\n", "\n", "# calculations \n", "V1 = math.sqrt((h2-h1)*2*32.2/(0.5+f1*l +1));\n", "R1 = V1/0.00000141;\n", "f2 = 0.019;\n", "V2 = math.sqrt((h2-h1)*2*32.2/(0.5+f2*l +1));\n", "R2 = V1/0.00000141;\n", "Q = 0.25*math.pi*(d/12)**2 *V2; \n", "\n", "# results \n", "print 'Velocity = %.1f fps \\\n", "\\nflow rate = %.1f cfs'%(V2,Q);\n", "\n", "\t\t#there is a minute error in the answer given in textbook" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Velocity = 12.5 fps \n", "flow rate = 9.8 cfs\n" ] } ], "prompt_number": 14 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.14 Page No : 322" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\t\t\n", "# variables\n", "l = 200.;\t\t#ft\n", "Q = 0.1;\t\t#cfs\n", "del_h = 5.;\t\t#ft\n", "T = 50.;\t\t#degreeF\n", "d = 0.187;\t\t#ft\n", "\n", "# calculations \n", "V = Q/(0.25*math.pi*d**2);\n", "R = V*d/0.0000141;\n", "f = (del_h*2*32.2/V**2 -(1+0.5))*(d/l);\n", "\n", "# results \n", "print 'Required diameter of the pipe = %.2f in.'%(d*12);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Required diameter of the pipe = 2.24 in.\n" ] } ], "prompt_number": 16 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.15 Page No : 324" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\t\t\n", "# variables\n", "Q = 2.5;\t\t#cfs\n", "T = 50.;\t\t#degreeF\n", "d1 = 8.;\t\t#in\n", "d2 = 6.;\t\t#in\n", "l1 = 1000.;\t\t#ft\n", "l2 = 2000.;\t\t#ft\n", "\n", "# calculations \n", "V8 = Q/(0.25*math.pi*(d1/12)**2);\n", "V6 = Q/(0.25*math.pi*(d2/12)**2);\n", "R8 = V8*0.667/0.0000141;\n", "f8 = 0.020;\n", "R6 = V6*0.5/0.0000141;\n", "f6 = 0.019;\n", "h_L8 = f8*(l1/0.667)*(V8**2 /(2*32.2));\n", "h_L6 = f6*(l2/0.5)*(V6**2 /(2*32.2));\n", "Ep = 100+h_L8+h_L6;\n", "n = Q*62.4*(Ep)/550;\n", "V8 = math.sqrt((30/f8)*2*32.2/(l1/0.667));\n", "Q_max = V8*0.25*math.pi*(d1/12)**2;\n", "\n", "# results \n", "print 'Maximum reliable flow that can be pumped = %.1f cfs'%(Q_max);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Maximum reliable flow that can be pumped = 2.8 cfs\n" ] } ], "prompt_number": 18 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.16 Page No : 327" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\t\t\n", "# variables\n", "Q = 5.;\t\t#cfs\n", "d = 12.;\t\t#in\n", "l = 5000.;\t\t#ft\n", "h = 70.;\t\t#ft\n", "L = 2000.;\t\t#ft\n", "\n", "# calculations \n", "K = (h/Q**1.85);\n", "a = (L/l)*K;\n", "b = ((l-L)/l)*K;\n", "Q_ = (h/((b+a*(0.5**(1.85)))))**(1/1.85);\n", "Q_A = Q_/2;\n", "Q_B = Q_/2;\n", "del1 = Q_-Q;\t\t#gain capcaity\n", "percent = (del1/Q)*100;\t\t#gain percentage\n", "\n", "# results \n", "print 'The gain of capacity by looping the pipe is %.1f cfs or %d percentage'%(del1,percent);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The gain of capacity by looping the pipe is 1.0 cfs or 20 percentage\n" ] } ], "prompt_number": 19 } ], "metadata": {} } ] }