2 files changed, 115 insertions, 0 deletions
diff --git a/764/CH12/EX12.9.b/result12_9.txt b/764/CH12/EX12.9.b/result12_9.txt
new file mode 100755
index 000000000..6cf2d5555
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+++ b/764/CH12/EX12.9.b/result12_9.txt
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+-->//(Brakes) Example 12.9
+ 
+-->//Face width of the friction lining w (mm)
+ 
+-->w = 50
+ w  =
+ 
+    50.  
+ 
+-->//Maximum intensity of normal pressure pmax (N/mm2)
+ 
+-->pmax = 1
+ pmax  =
+ 
+    1.  
+ 
+-->//Coefficient of friction mu
+ 
+-->mu = 0.3
+ mu  =
+ 
+    0.3  
+ 
+-->//Radius of the drum R (mm)
+ 
+-->R = 250
+ R  =
+ 
+    250.  
+ 
+-->//All angles are taken from the same reference
+ 
+-->//Angles of the shoe theta1 and theta2
+ 
+-->theta1 = 15
+ theta1  =
+ 
+    15.  
+ 
+-->theta2 = 75
+ theta2  =
+ 
+    75.  
+ 
+-->//Maximum normal pressure occurs at angle fi (deg)
+ 
+-->if (theta2 > 90)
+-->    fi = 90
+-->else
+-->    fi = theta2
+ fi  =
+ 
+    75.  
+-->end
+ 
+-->//Distance of the force from the horizontal centerline d1 (mm)
+ 
+-->d1 = 200
+ d1  =
+ 
+    200.  
+ 
+-->//The distance of the pivot from the axis of the brake drum h (mm)
+ 
+-->h= 200
+ h  =
+ 
+    200.  
+ 
+-->//Distance of the pivot from the vertical centerline d2 (mm)
+ 
+-->d2 = 50
+ d2  =
+ 
+    50.  
+ 
+
+Actuating force(P) = 5025.457606 N
+
+Torque absorbing capacity of the brake with 4 shoes(Mt) = 2181614.276244 N-mm
+ 
+\ No newline at end of file
diff --git a/764/CH12/EX12.9.b/solution12_9.sce b/764/CH12/EX12.9.b/solution12_9.sce
new file mode 100755
index 000000000..f219618a5
--- /dev/null
+++ b/764/CH12/EX12.9.b/solution12_9.sce
@@ -0,0 +1,34 @@
+
+//Obtain path of solution file
+path = get_absolute_file_path('solution12_9.sce')
+//Obtain path of data file
+datapath = path + filesep() + 'data12_9.sci'
+//Clear all
+clc
+//Execute the data file
+exec(datapath)
+//For RIGHT SHOE
+//Calculate the moment of the frictional force about the pivot Mf (N-mm)
+Mf = mu * pmax * R * w * (4 * R * (cosd(theta1) - cosd(theta2)) - h * (cosd(2 * theta1) - cosd(2 * theta2)))/(4 * sind(fi))
+//Calculate the moment of the normal force about the pivot Mn (N-mm)
+Mn = pmax * R * w * h * (2 * (theta2 - theta1) * (%pi/180) - (sind(2 * theta2) - sind(2 * theta1)))/(4 * sind(fi))
+//Calculate the actuating force P (N)
+P = (Mn - Mf)/d1
+//Calculate the torque absorbing capacity Mtr
+Mtr = mu * R^2 * pmax * w * (cosd(theta1) - cosd(theta2))/sind(fi)
+//For LEFT SHOE
+//Assume the maximum intensity of pressure for LEFT SHOE to be 1 N/mm2 plmax
+plmax = 1
+//Calculate the moment of the frictional force about the pivot Mfl (N-mm)
+Mlf = Mf * plmax/pmax
+//Calculate the moment of the normal force about the pivot Mnl (N-mm)
+Mln = Mn * plmax/pmax
+//Calculate the actual maximum intensity of pressure plmax (N/mm2)
+plmax = P * d1/(Mlf + Mln)
+//Calculate the torque absorbing capacity Mtl (N-mm)
+Mtl = Mtr * (plmax/pmax)
+//Calculate the total torque absorbing capacity of the brake Mt (N-mm)
+Mt = Mtr + Mtl
+//Print results
+printf("\nActuating force(P) = %f N\n",P)
+printf("\nTorque absorbing capacity of the brake with 4 shoes(Mt) = %f N-mm\n",2*Mt)