Forced Vortex Flow

Forced Vortex Flow is an example of rotational flow and can be generated by rotating a cylinder containing a fluid about its axis or by rotating a paddle in a large volume of fluid. Under steady conditions, each particle will move with the same angular velocity and there will not be any relative motion between fluid particles. Streamlines for such a flow will be concentric circles and the total energy is constant along a streamline but varies from one streamline to another.

Scope of Experimentations:

• Fill the cylinder with water to about one half of its height
• Rotate the cylinder with constant and reasonably fast speed
• The free surface of the water takes the form of a parabolic profile
• Measure the speed of rotation
• When conditions become steady, take the surface profile readings by traversing the Pitot-static tube, immersed just beneath the water surface along a radial line The surface elevation at r0 is taken as the datum for all these readings
• Now for the second run, speed from motor has been changed and again at steady state, take the surface profile readings

Utilities Required:

• Power supply: Single Phase, 220 volts, 50 Hz, 5 Amp with earth
• Water Supply
• Drain

Technical Details:

• Do not run the pump at low voltage i.e. less than 180 Volts
• Always keep apparatus free from dust
• To prevent clogging of moving parts,  pump at least once in a fortnight
• Frequently Grease/Oil the rotating parts, once in three months
• Always Use Clean Water
• If the Apparatus is not in use for more than one month, drain the apparatus completely, and fill pump with cutting oil