{
"metadata": {
"name": "",
"signature": "sha256:62ceb66cf48441d19499a6332c57808da0a2f8834a586c75e2d7d1a835c045df"
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"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 9 : Impact of Jets"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.1 Page No : 171"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math \n",
"\n",
"#initialisation of variables\n",
"d= 2. \t #in\n",
"V= 210. \t#ft/sec\n",
"V1= 50. \t#ft/sec\n",
"g= 32.2 \t#ft/sec**2\n",
"w= 62.4 \t#lb/ft**3\n",
"\n",
"#CALCULATIONS\n",
"M= math.pi*V*w/(4*36*g)\n",
"F= M*V\n",
"dV= V-V1\n",
"M1= math.pi*dV*w/(4*36*g)\n",
"F1= M1*dV\n",
"W= F1*V1\n",
"F2= M*dV\n",
"W1= F2*V1\n",
"\n",
"#RESULTS\n",
"print 'Force on plate = %.f lb'%(F+1)\n",
"print ' Force on plate = %.f lb'%(F1)\n",
"print ' Work done/sec = %.f ft-lb/sec'%(W)\n",
"print ' Force on plate = %.f lb'%(F2)\n",
"print ' Work done/sec = %.f ft-lb/sec'%(round(W1,-3))\n",
"\n",
"#The answer is a bit different due to rounding off error in textbook\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Force on plate = 1865 lb\n",
" Force on plate = 1082 lb\n",
" Work done/sec = 54116 ft-lb/sec\n",
" Force on plate = 1421 lb\n",
" Work done/sec = 71000 ft-lb/sec\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.2 Page No : 172"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"import math \n",
"\n",
"#initialisation of variables\n",
"v1= 15. \t#ft/sec\n",
"v2= 40. \t#ft/sec\n",
"a= 30. \t#degrees\n",
"b= 150. \t#degrees\n",
"v= 15.27 \t#ft/sec\n",
"g= 32.2 \t#ft/sec**2\n",
"\n",
"#CALCULATIONS\n",
"a1= a-math.degrees(math.sin(v1*math.sin(math.radians(b))/v2))\n",
"w= math.cos(math.radians(a1))*v2\n",
"vr= v2*math.sin(math.radians(a1))/math.sin(math.radians(a))\n",
"v1= math.sqrt(v1**2+vr**2-2*v1*vr*math.cos(math.radians(a)))\n",
"r= 180-math.sin(math.radians(a))*vr/v\n",
"w1= v*math.cos(math.radians(r))\n",
"W= v1*(w-w1)/g\n",
"\n",
"#RESULTS\n",
"print 'a = %.2f degrees'%(a1)\n",
"print ' w = %.2f ft/sec'%(w)\n",
"print ' vr = %.2f ft/sec'%(vr)\n",
"print ' v1 = %.2f ft/sec'%(v1)\n",
"print ' w = %.2f ft/sec'%(w)\n",
"print ' Work done per pound = %.2f ft-lb/lb'%(W)\n",
"\n",
"# Note : Answers are different because of rounding off error."
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"a = 19.32 degrees\n",
" w = 37.75 ft/sec\n",
" vr = 26.47 ft/sec\n",
" v1 = 15.42 ft/sec\n",
" w = 37.75 ft/sec\n",
" Work done per pound = 25.39 ft-lb/lb\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.3 Page No : 173"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"import math \n",
"\n",
"#initialisation of variables\n",
"d= 0.5 \t#in\n",
"a= 165. \t#degrees\n",
"W= 7.35 \t#lb\n",
"W1= 500. \t#lb\n",
"t= 148. \t#sec\n",
"g= 32.2 \t#ft/sec**2\n",
"w= 62.3 \t#lb/ft**3\n",
"\n",
"#CALCULATIONS\n",
"Q= W1/(t*w)\n",
"v= Q*16*144/math.pi\n",
"dv= v*(1-math.cos(math.radians(a)))\n",
"F= dv*W1/(t*g)\n",
"r= W/F\n",
"k= (1-(W*t*g/(W1*v)))/math.cos(math.radians(a))\n",
"\n",
"#RESULTS\n",
"print 'k = %.3f '%(k)\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"k = 0.788 \n"
]
}
],
"prompt_number": 13
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.4 Page No : 174"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math \n",
"\n",
"#initialisation of variables\n",
"t= 0.25 \t#in\n",
"a= 30. \t#degrees\n",
"w= 480. \t#lb/ft**3\n",
"h= 2. \t#in\n",
"d= 0.5 \t#in\n",
"l= 6. \t#in\n",
"w1= 62.4 \t#lb/ft**3\n",
"g= 32.2 \t#ft/sec**2\n",
"\n",
"#CALCULATIONS\n",
"W= t*l**2*w/1728\n",
"M= w1*math.pi*d**2*math.cos(math.radians(a))/(g*4*144)\n",
"v= math.sqrt(W*(l/2)*math.sin(math.radians(a))/(M*2*(1./math.cos(math.radians(a)))))\n",
"\n",
"#RESULTS\n",
"print 'Velocity of jet = %.1f ft/sec'%(v)\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Velocity of jet = 26.6 ft/sec\n"
]
}
],
"prompt_number": 18
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.5 Page No : 176"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math \n",
"\n",
"#initialisation of variables\n",
"V= 90. \t#ft/sec\n",
"a= 30. \t#degrees\n",
"u= 45. \t#ft/sec\n",
"\n",
"#CALCULATIONS\n",
"w= V*math.cos(math.radians(a))\n",
"f= math.sqrt(V**2-w**2)\n",
"tanb= (math.atan(math.radians(f/(w-u))))\n",
"b = math.degrees(math.tan(tanb))\n",
"b = math.degrees(math.atan(b))\n",
"V1= math.sqrt(f**2+(u-f*1./math.tan(math.radians(b)))**2)\n",
"\n",
"#RESULTS\n",
"print \"B = %.2f degrees\"%b\n",
"print 'absolute velocity of water at the exit = %.1f ft/sec'%(V1)\n",
"\n",
"# rounding off error"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"B = 53.79 degrees\n",
"absolute velocity of water at the exit = 46.6 ft/sec\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.6 Page No : 177"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math \n",
"\n",
"#initialisation of variables\n",
"u= 734. \t#ft/sec\n",
"v= 2000. \t#ft/sec\n",
"g= 32.2 \t#ft/sec**2\n",
"da= 0.019 \t#kg/m**3\n",
"\n",
"#CALCULATIONS\n",
"W= g*v/(v-u)\n",
"A= W/(u*da)\n",
"\n",
"#RESULTS\n",
"print 'Weight of the air = %.1f lb/sec'%(W)\n",
"print ' Area of inlet = %.2f ft**2'%(A)\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Weight of the air = 50.9 lb/sec\n",
" Area of inlet = 3.65 ft**2\n"
]
}
],
"prompt_number": 23
}
],
"metadata": {}
}
]
}