CLOSED CIRCUIT BERNOULLI’S APPARATUS
AIM OF THE EXPERIMENT
To verify Bernoulli’s equation with the help of closed circuit Bernoulli’s apparatus.
a) Bernoulli’s apparatus.
b) Stop watch
DESCRIPTION OF EQUIPMENT
This unit consists of supply chamber and interlinking experimental duct kept horizontally
with transparent sides, made out of Perspex sheets for the purpose of absorbing the flow. The
interlinking duct is smoothly varying in cross-section, so that the velocity of flow changes
gradually for the purpose of experiments with minimum of frictional loss due to turbulence.
Piezometer glass tubes are provided at suitable intervals along the duct for the measurement
of pressure head at measurement of rate of flow. A special fitting with cork is provided for
discharging colored liquid at the inlet of the duct for visualization of streamline flow.
Suitable size of sump is provided to store adequate water for doing experiment. This is
arranged with flow space of the main unit. Pour adequate water in the sump leaving 25mm at
the top. 0.25 HP single phase mono block pump set is rigidly fixed in the unit, which operates
on single phase ac supply and pump the adequate water to the supply chamber through proper
piping system. The pump should be primed before starting.
According to Bernoulli’s theorem, in continuous liquid flow, total head along the flow is the
same i.e. datum head, pressure head, velocity head is constant at different points.
ZA+ (PA/w) + (VA2/2g) = ZB+ (PB/w) + (VB2/2g)
(PA/w) + (VA2/2g) = (PB/w) + (VB2/2g)
The sump is filled with water up to ¾ of the tank level.
The machine is kept main switch on.
The pump is started.
The pressure head is measured directly from the piezometric tubes and scales at
seven experimental points, along the experimental duct at suitable intervals.