Free & Forced Vortex Lab Reports

1.0 ABSTRACTS ABSTRACTS

This experiment about free and forced vortex.

2.0 INTRODUCTION

Analysis of fluid flow is often accomplished by simplifying assumptions with respect to the kinematics of the flow, by assuming simplified patterns of fluid motion as represented by streamlines. Vortex motion is a basic flow pattern; it is defined as motion in circular paths. There are two types of vortices distinguished in the dynamics of the motion and the resulting velocity distributions. These are forced and free vortices. The forced vortex is caused by external forces on the fluid such as the impeller of a pump. In a forced vortex motion, the fluid mass is made to rotate by means of some external source of  power, which exerts a constant torue on the fluid mass and, therefore, the fluid mass rotates with a constant angular velocity. !or example, a vertical cylinder containing liuid and rotating around its central axis with a constant angular velocity flow through the impeller of a centrifugal pump. In the free vortex motion, the fluid mass rotates without any external force. It rotates either by internal action or due to some rotation previously imported to it. !or example, flow through an opening at the bottom of a shallow vessel such as washbasin or a bath tub, flow around a  bend, whirpools, or tornadoes. In this experiment, a forced vortex is created by a rotating plate filled with blades while free vortex is created by only a rotating plate.

3.0 OBJECTIVES

".

To determine the surface profile of a forced vortex.

#. To investigate the physical phenomena associated with a free vortex

RESULTS Experiment 1: Free Vortex

Diameter at Centre, D (mm)

Measure d Height, h (mm)

Pitot Tube Head Differenc e, H (mm)

Pressure Head / Depth of the Pitot Tube, X (mm)

r (mm)

r² (mm²)

1/r² (1/mm²)

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Experiment 2: Forced Vortex

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Diamete r at Centre, D (mm)

Measure d Height, h (mm)

Pitot Tube Head Differenc e, H (mm)

Pressure Head / Depth of the Pitot Tube, X (mm)

r (mm)

r² (mm²)

1/r² (1/mm²)

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Experiment Va%&es Experiment 2: Forced Vortex Distance from Centre(mm)

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Calculated value :

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Distance from Centre(mm)

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