Design lab Experiments


Motorized Gyroscope Apparatus

Motorized Gyroscope Apparatus

The set up consists of heavy stainless steel disc mounted on a horizontal shaft, rotated by a variable speed motor.  The rotor shaft is coupled to a motor mounted on a trunion frame having bearings in a yoke frame, which is free to rotate about vertical axis. A weight pan on other side of disc balances the weight of motor.  Rotor disc can be move about three axis.  Torque can be applied by calculating the weight and distance of weight from the center of rotor.  The gyroscopic couple can be determined.

 

Scope Of Experimentation:

·         Experimental justification of the equation T = l w.  wp for calculating the gyroscopic couple by observation and measurement of results for  independent vibrations in applied couple T and precession wp.

·         To study the gyroscopic effect of a rotating disc.

·         Observation of gyroscopic effect of rotating disc.

Utilities Required:

·         Electric supply

o    230 V AC, Single Phase.

·         Bench area

o    1m x 1m

·         Tachometer to find out RPM of disc.

Technical Details:

·         Disc

o    Material

§  Stainless Steel

o    Dia

§  300 mm x 12 mm thick precisely balanced which can be rotated in 3 mutually perpendicular axis.

·         Motor

o    Variable speed of standard make. Supplied with Speed Control Unit.

·         Weights

o    2 kg, 1 kg, ½ kg..

·         Stop Watch

o    Electronic

·         Accurately marked scale & pointer to measure precession rate.

Journal Bearing Apparatus

Journal Bearing Apparatus

The apparatus consists of a plain steel shaft excavated in a bearing and directly driven by a FHP Motor. The bearing is freely supported on the shaft and sealed at the motor end. The speed of the motor is controlled accurately by the speed control unit and it can be made run in both directions. Twelve equal-spaced pressure taping around the circumference and four along the axis are provided and are connected to manometer by PU Tubing so that the pressure head of oil in all tubes can be observed at a time. The bearing can be loaded by attaching weights to the arm supported beneath it.

 

Scope Of Experimentations:

·         To study the pressure profile of lubricating oil at various conditions of load and speed.

·         Plotting the Cartesian polar pressure curves.

·         To measure the frictional torque and power transmit.

Utilities Required:

·         Electric supply

o    230 V AC, Single Phase.

·         Bench area

o    1.5 x 1.5 x 4 m

·         Tachometer to find out RPM of journal.

·         Oil

o    SAE 40 about 5 Ltrs.

TECHNICAL DETAILS:

·         Journal

o    Diameter 50 mm

·         Bearing

o    Diameter 55 mm

·         Weights

o    4 adjustable weights.

·         Motor

o    Variable speed FHP Motor

·         Control Panel

o    For speed control of motor.

·         Manometer

o    16 Tubes.

·         Oil recommended

o    SAE 40

Whirling Of Shaft Apparatus

Whirling Of Shaft Apparatus

When the natural frequency of a system coincides with the external forcing system frequency the phenomenon is called resonance. The speed at which resonance occurs is known as critical speeds. These speeds are also called whirling speeds or whipping..

Scope Of Experimentation:-

(1) Supported end conditions: Make use of end blocks with single self-aligning bearing.
(2) Fixed end conditions: -Make use of end blocks with double bearing. The guards D1 & D2 can be fixed at any position on the supporting bar frame, which fits on side support F. Rotating shafts are to be fitted in blocks in A &B stands. .

Utilities Required:-

The driving motor is 230V DC 1/16
H.P; 6500 RPM. A dimmer state of 240v, 2amp, and 50 cycles is used to control speed of the rotating shaft.

Equipment  Details :-

(A)     Coupling: – A flexible shaft is used to drive the test shaft from motor.
(B)     Ball bearing fixing ends:- The ends fix the shaft while it rotates. The shaft & the end-fixing device can be replaced within a short time with the help of this unit. The fixing ends provide change of end fixing condition of the rotating shaft as per the requirement.

Universal Governor Apparatus

Universal Governor Apparatus

The drive unit consists of a DC electric motor connected through belt and pulley arrangement. Motor and test set up are mounted on a M.S. fabricated frame. The governor spindle is driven by motor through V belt and is supported in a ball bearing.

The optional governor mechanisms can be mounted on spindle. Digital speed is controlled by the electronic control unit. A rpm indicator with sensor to determine the speed.  A graduated scale is fixed to the sleeved and guided in vertical direction.

The center sleeve of the porter and propel governors incorporates a weight sleeve to which weights may be added. The hart Nell governor provides means of varying spring rate and initial compression level and mass of rotating weight. This enables the hart Nell governor to be operated as a stable or unstable governor. The unit is designed to exhibit the characteristics of the spring loaded governor and dead weight governor.

The unit can perform following experiments:

  • Watt
  • Porter
  • Proell
  • Hartnell type governors
  • Determination of characteristic curve of sleeve position against controlling force and speed
  • Plotting of characteristic curves of radius of rotation

Specification:

DC Motor with drive: ½ HP motor & DC drive control for speed variation

Separate linkages for governor arrangements mentioned above are provided using same motor and base.  Speed measurement is done by digital rpm indicator sleeve displacement is to be noted on the scale provided. Variable speed control unit is provided with the apparatus.  Following experiments can be conducted on the gravity controlled governor apparatus i.e., for Watt Governor, Porter Governor and Proell Governor and also on Spring Loaded Governor.

  • Obtaining the graph of Governor Speed V/s Sleeve displacement.
  • Obtaining the governor characteristics i.e., the graph of controlling force V/s radius of rotation of the ball center.

Procedure:

  • Install the equipment firmly on a table near a single phase 50 Hg A.C. power supply.  Assemble the desired governor arms.
  • Check the assembly for any loose fittings.
  • Ensure that speed control the knob is at the minimum position.
  • Switch ON the mains.
  • Rotate the speed control knob slowly to get the desired RPM or sleeve displacement.
  • Allow it to stabilize.
  • Note down the sleeve displacement and RPM.
  • Gradually increase the RPM to get the desired sleeve displacement or RPM.
  • Repeat the above procedure for all the governors except watt governor by adding different weights.
  • After the experiment is complete, gradually reduce the rpm to zero and then only switch OFF the system

Services required:

  • 50/60 Hz, as standard supply.±    Earthed A.C. Single Phase Electrical Supply, 200/250V.
Explore posts in the same categories: 7th sem study materials

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s


%d bloggers like this: