Lab mannaul

 Page 8/11 Date 29.04.2021 Size 286.02 Kb.

( iii )

THE APPARATUS -

The apparatus uses hydraulic analogy to determine coriolli's component of acceleration. The apparatus consists of two brass tubes connected to a central rotor distributor. The distributor is rotated by a variable speed d. c. motor. Water is supplied to a distributor by a pump through rotameter When tubes are rotating with water flowing through tubes, with various measurements provided, coriolli's component can be determined experimentally and theoretically.

SPECIFICATIONS -

1. Pipes — 6 mm 1. D. 310 mm. Effective length - 2Nos.

2. Drive motor 1 HP. 3000 rpm d. c. series motor, swinging field type with speed control.

3. Torque arm -Radius 0,057 m with 5 Kg. Capacity spring balance.

4. Pump - 0.5 H.P. capacity 25 x 25 mm connection single ph.

5. Rotameter - 250 to 2500 liters per hour capacity.

6. Housing for rotating pipes, which also acts as water reservoir, with two sides of perspex sheets

EXPERIMENTAL PROCEDURE

Fill up sufficient water in the tank. Rotate the coupling to ensure free rotation. Check the nut bolts for tightening. Start the motor and set the speed as required, e. g say 200 rpm. Measure the torque required for free rotation of tubes at that speed. (for measuring the torque, pointer over the torque arm must coincide with the stationary pointer, before taking spring balance reading.)

Now start the pump and adjust the flow rate with the help of bypass valve, so that water does not overflow through central glass tube and also pipes run full of water Now adjust the speed to Drevious value and measure the torque. Note down water flow rate.

Repeat the procedure at different speeds.

OBSERVATIONS-

 Sr. NO. Speed N Spring balance ( Kq) Water flow ( rpm ) Initial Final ( LPH )

CALCULATIONS -
1) Bore dia. Of tubes = 6 mm

Flow area of tube (a) = 2. 82 x 10-5 m2

Total flow area A = 5.65 x 10-5 m2
2) Flow rate = Q = L P H / 3.6 x 106 m3 / Sec.
. . Velocity of water through the tubes

Q

V =' ------—- m / s

A

1. Length of torque arm = 0.057 m

’. T = ( Spring bal. Difference ) x 0.057 Kg- m

1. Now theoretically ,

CA = 2 V ꞷ

= 2 V [2 π N / 60 ]

Practically ,

^ ^ 2 g T

CA = ------------------ m /Sec2 W . a. l 2
Where, W = Specific weight of water

= 1000 Kg /m3

I = Effective length of tube

= 0.310m

a = Flow area of tube

= 2.85 × 10-5

and T = Torque in Kg-m.

PRECAUTIONS -

1. While filling the water, see that there is sufficient gap between the tubes

and water surface.

1. Remove the glass tube with its water supply nozzle after the experiment

is over. Store glass tube safety,

1. Drain the water after the experiment is over.

2. Operate all the switches and controls gently.

COROLLI’S COMPONENT OF ACCELERATION