Question

A hydraulic circular rod having a 100mm diameter and 2m long is

pulled by a force of 200 N.

It moves with a constant velocity within a

circular hollow tube of 101mm internal diameter.

The clearance of

0.5mm between the rod and the tube is filled with oil of specific gravity

0.8 and kinematic viscosity 400 mm^2/s as shown in the figure below.

Determine the velocity of the rod in units of m/s.

Answer 1

Answer

Diameter of Rod D_rod=100mm

Length l=2m

Force F=200N

circular hollow tube of 101mm internal diameter. D_i=101mm

clearance SG=0.8

kinematic viscosity v=400 mm^2/s

So we can say

the velocity of the rod is given by

$V=\frac{Fh}{vSG\rho _{H20}\pi D_{rho}l}\\=\frac{200\times0.5\times10^{-3}}{400\times10^{-6}\times0.8\times1000\times3.14\times100\times10^{-3}\times2}$

$=0.5m/sec$