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diff --git a/Machine_Design_by_U.C._Jindal/Ch21_2.ipynb b/Machine_Design_by_U.C._Jindal/Ch21_2.ipynb new file mode 100644 index 00000000..269495fb --- /dev/null +++ b/Machine_Design_by_U.C._Jindal/Ch21_2.ipynb @@ -0,0 +1,350 @@ +{ + "cells": [ + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Ch:21 V belt drive" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## exa 21-1 - Page 579" + ] + }, + { + "cell_type": "code", + "execution_count": 3, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Tc is 140.5 N \n", + "\n", + "T1 is 483 N \n", + "\n", + "T2 is 288.2 N \n", + "\n", + "P2 is 4589 W \n", + "\n", + "n is 3 \n" + ] + } + ], + "source": [ + "from __future__ import division\n", + "from math import sqrt, pi, asin, degrees, exp\n", + "P1=12*10**3#\n", + "d=0.3#\n", + "D=0.9#\n", + "C=0.9#\n", + "A=230*10**-6#\n", + "#density is rho\n", + "rho=1100#\n", + "N=1500#\n", + "#Maximum stress is sig\n", + "sig=2.1*10**6#\n", + "#semi groove angle is b\n", + "b=20*pi/180#\n", + "u=0.22#\n", + "m=rho*A#\n", + "v=2*pi*N*d/(60*2)#\n", + "Tc=m*v**2#\n", + "T1=A*sig#\n", + "#wrap angle is thetaA\n", + "ang=(D-d)/(2*C)#\n", + "thetaA=pi/180*(180-(2*degrees(asin(ang))))\n", + "thetaB=((2*pi)-thetaA)#\n", + "x=u*thetaB#\n", + "T2=Tc+((T1-Tc)/exp(x))#\n", + "P2=(T1-T2)*v#\n", + "n=P1/P2#\n", + "n=3# #(rounding off to nearest whole number)\n", + "print \"Tc is %0.1f N \"%(Tc)#\n", + "print \"\\nT1 is %0.0f N \"%(T1)#\n", + "print \"\\nT2 is %0.1f N \"%(T2)#\n", + "print \"\\nP2 is %0.0f W \"%(P2)#\n", + "print \"\\nn is %0.0f \"%(n)#\n", + " \n", + " " + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## exa 21-2 - Page 579" + ] + }, + { + "cell_type": "code", + "execution_count": 4, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Tc is 107.15 N \n", + "\n", + "T1 is 3290 N \n", + "\n", + "T2 is 98.93 N \n", + "\n", + "Lp is 3.239 m \n", + "\n", + "v is 74.15 m/s \n", + "\n", + "The designation of the belt is B-3251-45 \n" + ] + } + ], + "source": [ + "from math import sqrt, pi, asin, degrees, exp,sin\n", + "D=0.6#\n", + "d=0.3#\n", + "C=0.9#\n", + "m=0.193#\n", + "n=2#\n", + "N=1500#\n", + "u=0.3#\n", + "v=2*pi*N/60*d/2#\n", + "P=150*10**3#\n", + "Tc=m*v**2#\n", + "#let T1-T2=T\n", + "T=P/(n*v)#\n", + "thetaA=pi/180*(180-(2*degrees(asin((D-d)/(2*C)))))#\n", + "thetaB=((2*pi)-thetaA)#\n", + "#Groove angle=b\n", + "b=17.5*pi/180#\n", + "x=u*thetaA/sin(b)#\n", + "y=exp(x)#\n", + "c=(Tc*(1-y))#\n", + "T2=(T+(Tc*(1-y)))/(y-1)#\n", + "#T2=(T-y)/Tc#\n", + "T1=T+Tc#\n", + "Lp=2*sqrt((C**2)-((D-d)/2)**2)+(thetaA*d/2)+(thetaB*D/2)#\n", + "v=sqrt(T/(3*m))#\n", + "print \"Tc is %0.2f N \"%(Tc)#\n", + "print \"\\nT1 is %0.0f N \"%(T1)#\n", + "print \"\\nT2 is %0.2f N \"%(T2)#\n", + "print \"\\nLp is %0.3f m \"%(Lp)#\n", + "print \"\\nv is %0.2f m/s \"%(v)#\n", + "print \"\\nThe designation of the belt is B-3251-45 \"#\n", + "#The difference in values of T1 and T2 is due to rounding-off of values." + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## exa 21-3 - Page 580" + ] + }, + { + "cell_type": "code", + "execution_count": 5, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Tc is 59.97 N \n", + "\n", + "T1 is 520.7 N \n", + "\n", + "T2 is 102.7 N \n", + "\n", + "n is 4.0 \n", + "\n", + "Lp is 3.410 m \n", + "\n", + "The designation of the belt is C-3414-47 \n" + ] + } + ], + "source": [ + "from math import sqrt, pi, asin, degrees, exp,tan\n", + "C=1#\n", + "m=0.35#\n", + "d=0.25#\n", + "P=22*10**3#\n", + "#Let the smaller pulley dia be n\n", + "#Let the larger pulley dia be N\n", + "n=1000#\n", + "N=400#\n", + "D=d*n/N#\n", + "v=2*pi*n*d/(60*2)#\n", + "Tc=m*v**2#\n", + "topwidth=22#\n", + "h=14#\n", + "bottomwidth=topwidth-(2*h*tan(20*pi/180))#\n", + "A=(topwidth+bottomwidth)/2*h#\n", + "#let allowable tension be Ta\n", + "Ta=2.2#\n", + "T1=A*Ta#\n", + "u=0.28#\n", + "thetaA=pi/180*(180-(2*degrees(asin((D-d)/(2*C)))))\n", + "thetaB=((2*pi)-thetaA)#\n", + "#Groove angle=b=19\n", + "b=19*pi/180#\n", + "x=u*thetaA/sin(b)#\n", + "T2=Tc+((T1-Tc)/exp(x))#\n", + "n=P/((T1-T2)*v)#\n", + "Lp=2*sqrt((C**2)-((D-d)/2)**2)+(thetaA*d/2)+(thetaB*D/2)#\n", + "print \"Tc is %0.2f N \"%(Tc)#\n", + "print \"\\nT1 is %0.1f N \"%(T1)#\n", + "print \"\\nT2 is %0.1f N \"%(T2)#\n", + "print \"\\nn is %0.1f \"%(n)#\n", + "print \"\\nLp is %0.3f m \"%(Lp)#\n", + "print \"\\nThe designation of the belt is C-3414-47 \"#\n", + " \n", + "# difference in value of Lp is due to rounding-off the values of thetaA and thetaB." + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## exa 21-4 - Page 580" + ] + }, + { + "cell_type": "code", + "execution_count": 6, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "D is 600.0 mm \n", + "\n", + "C is 1000.0 mm \n", + "\n", + "n is 3.000 \n", + "\n", + "Li is 3252 mm \n" + ] + } + ], + "source": [ + "from math import sqrt, pi\n", + "P=12*10**3#\n", + "Ks=1.1#\n", + "Pd=12*10**3*Ks#\n", + "N=1440#\n", + "B=17#\n", + "t=11#\n", + "d=200#\n", + "i=3#\n", + "D=i*d#\n", + "C=1000#\n", + "# since angle of contact theta is very small\n", + "theta=(D-d)/C#\n", + "theta=theta*180/pi#\n", + "Kc=0.8#\n", + "Lp=(2*C)+(pi/2*(D+d))+(((D-d)**2)/(4*C))#\n", + "Li=Lp-45#\n", + "Ki=1.1#\n", + "#let number of v-belts required = n\n", + "#let the KW rating be KWR\n", + "KWR=5.23#\n", + "n=(P*Ks)/(KWR*Ks*Ki*10**3)#\n", + "n=3#\n", + "print \"D is %0.1f mm \"%(D)#\n", + "print \"\\nC is %0.1f mm \"%(C)#\n", + "print \"\\nn is %0.3f \"%(n)#\n", + "print \"\\nLi is %0.0f mm \"%(Li)" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## exa 21-5 - Page 581" + ] + }, + { + "cell_type": "code", + "execution_count": 7, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + " C is 1.0603 m \n", + "\n", + " Pd is 30 KW \n", + "\n", + " n is 4.01 KW \n" + ] + } + ], + "source": [ + "from sympy import symbols, solve\n", + "from math import pi\n", + "N=800;\n", + "P=20;\n", + "i=2.5;\n", + "Ks=1.5; #(from table for 3-5 hrs/day)\n", + "Pd=P*Ks;\n", + "d=250;\n", + "D=i*d;\n", + "C=1.6*D;\n", + "Lp=(2*C)+(pi*(D+d)/2)+((D-d)**2)/(4*C);\n", + "Li=Lp+74;\n", + "Listd=3454;\n", + "Lp=Listd+74;\n", + "p=[1, -1.0768, 0.0175];\n", + "P = symbols('P')\n", + "expr = P**2*p[0]+P*p[1]+p[2]\n", + "z = solve(expr, P)[1]\n", + "KW=9.4;\n", + "Kc=0.795;\n", + "K1=1;\n", + "n=Pd/(KW*Kc*K1);\n", + "print \" C is %0.4f m \"%(z)\n", + "print \"\\n Pd is %0.0f KW \"%(Pd)\n", + "print \"\\n n is %0.2f KW \"%(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": "2.7.9" + } + }, + "nbformat": 4, + "nbformat_minor": 0 +} |