Hydraulic Analoqy -
REF.FIG. B
Consider a short column of fluid of length dr at radius r from axis of rotation of the tube. Them if velocity of fluid relative to tube is V and angular velocity of tube is ꞷ then coriolli’s component of acceleration is 2 V ꞷ in a direction perpendicular to rotation of tube. The torque dT applied by the tube to produce this acceleration is then
dW
dT = ------------- 2 V ꞷ r
Where, dW is weight of short column of fluid.
If W be the specific weight of fluid and a is cross sectional area of tube, then ,
dW = W a dr
W a dr
dT = ----------- 2 V ꞷ r
g
and total torque applied to column of length I ,
I w
T = / 2 ---------- V ꞷ a . r. dr
0 g
W
T = ------------- w V . a I2
g
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