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EINSTEIN COLLEGE OF ENGINEERING Sir.C.V.Raman Nagar, Tirunelveli-12 Department of Mechanical Engineering ME57- Dynamics lab Name : ……………………………………… Reg No : ……………………………………… Branch : ……………………………………… Year & Semester : ……………………………………… Sub Code: ME57 Dynamics Lab TABLE OF CONTENTS Sl.No Date of Name of the Experiment Page Marks Staff Remarks Experiment No Initial 1 Determination of speed and sensitivity for watt governor 2 Determination of speed and sensitivity for proell governor 3 Determination of speed and sensitivity for porter governor Determination of speed and 4 sensitivity for hardnell governor 5 Determination of moment of inertia by oscillation method 6 Cam study model 7 Determination of whirling speed of shaft Page 1 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab 8 Balancing of rotating mass Verification of gyroscopic 9 relation 10 Study on balancing of reciprocating mass 11 Determination of natural frequency in vibrating table Multi degree of freedom suspension 12 Determination of natural 13 frequency of transverse vibration Page 2 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab DETERMINATION OF SPEED AND SENSITIVITY FOR WATT GOVERNOR DATE: EXP NO: 1 Aim: To determine the speed and sensitivity of the Watt Governor. Apparatus Required: 1.Watt governor set up. 2.tachometer 3.dimmer Formula: 1. Speed, N = √(895/h) rpm h-sleeve lift 2. Sensitivity= N/N2-N1 N2-Maximum speed N1-Minimum speed N-Mean speed Procedure: 1. The watt governor assembly is mounted over the spindle. 2. The motor is started and speed is adjusted. Speed is measured with the help of tachometer. 3. Due to this centrifugal force the sleeve will be rise, the speed and the sleeve height are noted. 4. By using the formula the speed of the governor is calculated. 5. The experiment is repeated at different speed and force. Page 3 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Tabulation: Sl.no Motor speed (rpm) Sleeve lift (h) Governor speed (N) (mm) (rpm) Calculation: Page 4 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Questions: 1) What is watt governor? 2) Difference between function of flywheel and governor? 3) What are the limitations of watt governor? 4) Explain working principle of watt governor? 5) What is height of a watt governor? Result: At different motor speed the sleeve lift are noted and corresponding governor speed and sensitivity are calculated. Page 5 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab DETERMINATION OF SPEED AND SENSITIVITY FOR PROELL GOVERNOR Date: Exp No:2 Aim: To determine the speed and sensitivity of the proell Governor. Apparatus Required: 1.Proell governor. 2.Tachometer. 3.Dimmer. Formula: N = √ FM/BM x (m+M/m) x 895/h. Where, FM/BM-proell link ratio =0.57. M-mass of the sleeve assembly=2.25kg m-mass of the ball = 0.092 kg. h-sleeve lift Sensitivity=N/N2-N1 N2-Maximum speed N1-Minimum speed N-Mean speed Procedure: 1. The proell governor assembly is mounted over the spindle. 2. The motor is started and speed is adjusted. Speed is measured with the help of tachometer. 3. Due to this centrifugal force the sleeve will be rise, the speed and the sleeve height are noted. 4. By using the formula the speed of the governor is calculated. 5. The experiment is repeated at different speed and force. Page 6 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Tabulation: Sl.NO MOTOR SLEEVE LIFT(h) GOVERNORSPEED( N) SPEED (rpm) (mm) rpm Calculation: Page 7 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Questions: 1) Explain proell governor working principle? 2) What is controlling force? 3) Explain the term “power of governor”? 4) Explain the term “Hunting of governor”? 5) Why is it that the speed ranges of a proell governor less than that of porter governor? Result: At different motor speed the sleeve lift are noted and corresponding governor speed and sensitivity are calculated. Page 8 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab DETERMINATION OF SPEED AND SENSITIVITY FOR PORTER GOVERNOR Date: Exp No:3 Aim: To determine the speed and sensitivity of the porter governor. Apparatus required: 1. Porter governor. 2. Tachometer. 3. Dimmer. Formula: 1. Governor speed n = √ (m+M/m) * (895/h) rpm. M-mass of the sleeve assembly =2.25 kg h-sleeve lift m-mass of the each ball=0.225 kg 2. Sensitivity= N/N2-N1 N-Mean speed N2-Maximum speed N1-Minimum speed Procedure: 1. The porter governor assembly is mounted over the spindle. 2. The motor is started and speed is adjusted. Speed is measured with the help of tachometer. 3. Due to this centrifugal force the sleeve will be rise, the speed and the sleeve height are noted. 4. By using the formula the speed of the governor is calculated. 5. The experiment is repeated at different speed and force. Page 9 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Tabulation: S.No Sleeve Lift (h) Governor speed (N) Motor Speed (rpm) (mm) (rpm) Calculation: Page 10 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Question: 1) Explain working principle of porter governor? 2) Explain the terms stable and unstable of governor? 3) What is spring controlled governor? 4) Define power of porter governor? 5) What is effort of porter governor? Result: At different motor speed the sleeve lift are noted and corresponding governor speed and sensitivity are calculated. Page 11 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab DETERMINATION OF SPEED AND SENSITIVITY FOR HART NELL GOVERNOR Date: Exp No:4 Aim: To determine the speed and sensitivity of the Hart Nell governor. Apparatus Required: 1. Hart Nell governor 2. Tachometer. 3. Dimmer. Formula: 1. Governor speed n = √ (m+M/m) * (895/h) rpm. M-mass of the sleeve assembly =2.25 kg h-sleeve lift m-mass of the each ball=0.225 kg 2. Sensitivity= N/N2-N1 N-Mean speed N2-Maximum speed N1-Minimum speed Procedure: 1. The porter governor assembly is mounted over the spindle. 2. The motor is started and speed is adjusted. Speed is measured with the help of tachometer. 3. Due to this centrifugal force the sleeve will be rise, the speed and the sleeve height are noted. 4. By using the formula the speed of the governor is calculated. 5. The experiment is repeated at different speed and force. Page 12 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Tabulation: Sl.No Motor Speed Sleeve Lift (h) Governor speed (N) (rpm) (mm) (rpm) Calculation: Page 13 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Question: 1) Compare gravity-controlled and spring controlled governor? 2) Working principle of hartnell governor? 3) What is sensitiveness of a governor? 4) Types of spring controlled governor? 5) Define centrifugal governor? Result: At different motor speed the sleeve lift are noted and corresponding governor speed and sensitivity are calculated. Page 14 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab DETERMINATION OF MOMENT OF INERTIA BY OSCILATION Date: Exp No:5 Aim: To determine the moment of inertia by oscillation method. Apparatus Required: 1. Fly wheel 3. Main Frame 2. Chucks 4. Connecting rod. Formula Used: 1. Polar moment of inertia (J) = /32xd4 m4 d-dia of the connecting rod ends 2. Torsional Rigidity (q) =GJ/l N-M G-Modulus of rigidity of material=0.79x1011 l-Length of the connecting rod 3. Moment of Inertia (I) =4q/ 2f2 =4qt2p/ 2 kg-m2 Procedure: 1. The connecting rod for which the moment of inertia is to be found is fixed the inner diameter of the rod is measured by various points. 2. The mean diameter is taken as the diameter of the rod. 3. The rod is fixed at both at the top of the chuck and the flywheel and the length between two points is measured then a small twist is given to the flywheel and is released. 4. The time taken for the 5 oscillation is noted in the tabular column. 5. The same experiment is repeated for various lengths and at different diameter the experiment is done by adding the weight of flywheel and the reading are noted down. Page 15 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Tabulation: Length of Diameter of Moment of rod rod inertia Sl.no End N T tp = position t/n (mm) (mm) Kg-m2 (sec) Calculation: Page 16 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Questions: 1) What is polar moment of inertia? 2) What is big end & small end? 3) What is the function of connecting rod? 4) What is “co-efficient of fluctuation of speed”? 5) What is mass moment of inertia? Result: Thus the moment of inertia of the given rod is calculated and tabulated. Page 17 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab CAM STUDY MODEL Date: Exp No:6 AIM: To draw the displacement diagram for various cam profile and various followers. APPARATUS REQUIRED: 1) Experimental setup 2) Flat, Roller, Knife edge follower 3) Cams PROCEDURE: 1.Taka a paper of size 40cm x 15cm, use scale for x-axis as 1cm = 10 of rotation of cam. 2.Take height of lift as10cm. 3. Plot displacement diagram for given cam profile. 4.Fit graph paper on drum. set ‘0’ as a starting point to lift. 5.Give gradual rotation to complot displacement diagram on graph. 6.Compare solution obtained by graphical. Do this for other cam profile and follower. Page 18 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Tabulation: Roller follower Mushroom follower Knife edge follower Degree Displacement Degree Displacement Degree Displacement Calculation: Page 19 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Question: 1) Classification of cams and followers? 2) Types of follower motion? 3) Explain cam function? 4) Define pressure angle? 5) Explain the term “maximum fluctuation of energy”? RESULT: Thus the displacement diagrams are drawn for the given follower and various cams. Page 20 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab DETERMINATION OF WHIRLING SPEED OF THE SHAFT Date: Exp No:7 Aim: To determine the whirling speed of a shaft at various supporting condition. Apparatus required: 1. Whirling shaft apparatus 2. Various support and bearings. 3. Tachometer 4. Vernier caliper 5. Steel rule Formula Used: 1. Deflection =h2-h1 cm h1-minimum deflection, h2-maximum deflection 2. Whirling speed=1/2 √g/ rpm g-gravity 9.81 Procedure: 1. First fixing the arrangement, are selected. 2. The shafts are fixed firmly on the suitable bearing and tighten it. 3. Then the motor is switched on and speed of the motor is increased. 4. The modes of shaft vibration are noted. By using the formula the frequency at various vibrations calculated. 5. Same procedure repeated using various diameter (4,6 and 8mm) of shaft. Page 21 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Tabulation: Sl.No Diameter Length Speed Weight of the shaft per unit Whirling speed of shaft of shaft length (w) (N) (rpm) (mm) (cm) h1 h2 δ rpm (cm) (cm) (cm) Calcultion: Page 22 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Questions: 1) What is whirling speed? 2) Define amplitude? 3) Define resonance? 4) What is Damper & types of damper? 5) Define degree of freedom? Result: Thus the whirling speed of the various shaft at various end condition are calculated. Page 23 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab BALANCING OF ROTATING MASS Date: Exp No:8 Aim: To verify the balancing using the rotating machine element. Apparatus required: 1. Balancing rotary system 2. Masses. Procedure: 1.To order of the basic operation involved with respect to static balancing as following 2.Then the mass should be fixed in one side of the stud and its angle to be adjusted with the help of angular scale and its radil can be corrected with the help of vernier caliper. 3.Angular displacement between the masses Is calculated by force diagram through known value of mass and radil. 4.Fix the masses to the calculated angular displacement using angular scale. 5.Now switch on the motor. 6.By changing the sped of the motor, check it out for vibration for running 7.Add by changing the mass with different radil and find out the angular displacement among the mass for balancing the system Page 24 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Tabulation: Sl.No Plane A B C D Mass Radius θ Calculation: Page 25 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Question: 1) What is meant by balancing? 2) What are the types of balancing? 3) What is reference plane? 4) What is turning moment diagram? 5) What is swaying couple? Result: Thus the Balancing Of Rotating Machine Was Verified. Page 26 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab VERIFICATION OF GYROSCOPIC RELATION Date: Exp No:9 Aim: To analysis the gyroscopic effect using the test setup and verify the gyroscopic rules of plane disc. Apparatus Required: 1. Gyroscopic setup. 2. Weight 3. Tachometer Technical Data: 1.Rotor diameter (d) = 30 cm. 2.Rotor thickness (t) = 8cm. 3.Distance of weight pan bolt centre to disc center (l) = 260 mm. 4.Weight of the rotor = 7kg. Formula Used: 1. Precision ratio (wp) = 2 n/60 rad/ sec. 2. Angular velocity (w)=dØ/dt X /180 rad/sec dØ-change in degree dt-time taken in sec 3. Gyroscopic effect (c) = I.ω.ωP 4. Torque, t = wxr Where, w = weight of the rotor. r = distance between weight pan centre to disc centre. 5. I = mr2/2 Kg-m2. m-mass of the rotor kg 6. Percentage of error = (T-C)/T X 100. Page 27 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Procedure: 1.Switch on the supply. 2.Set the require speed of the regulator as constant. 3.Add the load as ½ kg, 1kg etc. 4.Angle of precision d i.e. Measured. 5.Loose the lock screw, start the stop watch and note down. 6.Watch the particular interval and time. 7.Take the reading n different load. 8.Repeat the equipment maintaining load as constant and varying the speed. 9.Do the calculation. Tabulation: Speed Of Disc (rpm) Added weight dθ dt (gm) (degree) (sec) Angular velocity Applied couple on Precision ratio Gyroscopic Effect c tachometer (Tact) rad/sec (ω) (ωp) rad/sec N-m Page 28 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Calculation: Page 29 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Question: 1) Define gyroscopic couple? 2) What is gyroscopic torque? 3) Define Axis of precession & Axis of spinning 4) Explain gyroscopic Effect on naval ship? 5) Explain gyroscopic effect on aero plane? Result: Thus the Gyroscopic relation was verified. Page 30 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab STUDY ON BALANCING OF RECIPROCATING MASS Date: Exp No:10 Aim: To study the behavior of vibration due to the unbalanced mass in reciprocating parts. Apparatus required: Balancing of reciprocating mass system masses. Procedure: 1.Initially all weights and bolts are removed then the motor is started. The speed of the motor is increased due to the unbalanced masses, the vibration will be created. The vibration Is observed. 2.The speed is noted down. Now the speed is increased and the vibrations are all so noted down. The motor is switched off then some weights added on the piston top. The weights may be added on the piston top. The weights may be added either eccentrically (or) co- axially. Now the motor is started the vibrations are observed at the tested speed noted in the previous case. If still the vibration are observed. One of the following has to be done to eliminate the unbalance forces 3.Some weights are added in opposites direction of crank and the engine run and the vibration, are observed at the tested speed. 4.Combination of both the above cases. The speeds, the weight added on piston, diameter at which the weights are added are noted down at different case. Result: The vibrations due the unbalanced forces in the reciprocating masses are studied. Page 31 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab DETERMINATION OF NATURAL FREQUENCY USING VIBRATING TABLE Date: Exp No:11 Aim: To find natural frequency of free vibration and forced vibration using vibration table. Apparatus Required: 1) Spring 2) mass 3) damper 4) stopwatch 5) steel rule. Formula Used: Natural Frequency fn=N/T Hz N-No of oscillation T=Time period of 5 oscillations in sec Procedure: Free Vibration: 1) Remove the damper from the experimental setup. 2) Then strike the beam by taken 5 oscillation time required. 3) Repeat the procedure for different length of beam to adjust the beam set up. Forced Vibration: 1) Fit the spring, mass damper in proper position note down the spring stiffness, mass of the beam, length of the beam from one tunion point and measure the exciter mass. 2) The electrical motor is switched ON, using stop watch note down 5 oscillation time for small jerk. 3) Then repeat the procedure for different length of beam. Page 32 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Tabulation: Free vibration: Time required to complete one set of Exciter No of oscillation Time Frequency position oscillation period Sl.No Vibration (sec) ’T’ (Hz) Forced Vibration: Time period(T) S.No Vibration Exciter No of Frequency (Hz) Speed position oscillation (sec) (rpm) Page 33 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Calculation: Page 34 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Question: 1) What are different types of vibrating motions? 2) Define free vibration& forced vibration? 3) What is damping? 4) Define D’Alemberts principle? 5) Define critical speed? Result: Thus the natural frequency of free and forced vibration using vibrating tale was found. Page 35 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab MULTI DEGREE OF FREEDOM SUSPENSON Date: Exp No:12 Aim: To find out the mass moment of inertia of any irregular section. Apparatus required: 1) Bifilar and trifler setup 2) stopwatch 3) Different weight of cycle 4) steel rule Formula Used: Bifiller: 1) Natural Frequency fn=N/T Hz 2) Radius of Gyration k=1/2 fnx√g.ab/l 3) Moment of Inertia I=mk2 kg-m2 Where, N-No of oscillation ab-Distance between two nodes Fn-Natural Frequency in Hz l-length of the thread T-Time taken for 5 oscillations in sec k-Radius of gyration M-mass of the bifiller plate Trifiller: 1) Radius of gyration k=1/2 fnx√g.r2/l 2) Moment of inertia I=mk2 kg-m2 Where, r-Radius of the Trifiller m-mass of the trifiller g-Gravity (9.81) Page 36 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Procedure: 1) Select either of bifilar (or) trifler plates. 2) With the help of spring chucks lighter at tops. 3) Adjust the length of spring to descry the value (or) measure length on it. 4) Give small horizontal twist at the same time start the stop watch and note down time required for five (or) ten oscillation. 5) Repeat the experiment by adding weight and checking length. Tabulation: Radius Moment of of Inertia S.NO Types of Self No. of Time weight gyration Natural Suspensio weight oscilla Taken added K frequency I n tion (kg) sec (gm) (m) (fn) (Kg-m2) Hz Page 37 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Calculation: Page 38 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Questions: 1) Explain laws of motion? 2) What is free body diagram? 3) What is static& dynamic force Analysis? 4) Define simple harmonic motion? 5) Define crank pin effort & piston effort? Result: Thus the MI of irregular section find out. Page 39 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab DETERMINATION OF NATURAL FREQUENCY OF TRANSVERE VIBRATION Date: Exp No:13 Aim: To determine the natural frequency of free transverse vibration due to uniformly distrusted load and concentrated load over a simply supported shaft. Apparatus Required: 1. Shaft 2. Stop watch 3. Weight 4. Transverse vibration system. Formula Used: Simply supported Beam: 1. Uniform Distributed Load Frequency (fn) =0.571/√ 2. Point load Frequency (fn) =0.4985/√ 3. Varying load Frequency (fn) =0.4985/√ Cantilever Beam: 1. Cantilever Beam Frequency (fn) = (1/2 ) x√g/ g-Gravity -Deflection. Procedure: 1. First proper lubrication is done for the bearing. 2. The given beam is fitted into the slots of Turn ion bearings and they are tightened. 3. The weight is added according to the condition of loading whether is to be loaded uniformly or concentrated. Then the beam is given a swing and starts oscillating. 4. The time taken for five oscillations noted down. 5. The experiment is repeated for various types of loads and the types of beams. Page 40 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Tabulation: FREQUENCY (fn) Hz VARIYING BEA LOAD UDL POINT LOAD POINT LOAD M VARIYING DEFEL DEFEL TIM DEFEL TIME TIME CTION CTION E CTION LOAD UDL (sec) (sec) (cm) (cm) (sec) (cm) Observation: 1) Mass of the each weight (m)=158 gm 2) Length of the cantilever beam=235mm Calculation: Page 41 of 42 ©Einstein College of Engineering Sub Code: ME57 Dynamics Lab Questions: 1) Define “Logarithmic Decrement”? 2) Define” under damped”, “over damped” vibrations? 3) What is critical speed? 4) Define natural frequency? 5) What do you understand by whirling motion? Result: The natural frequency of transverse vibration due to UDL and concentrated load over a simply supported shaft is calculated and is compared with experimental value. Page 42 of 42 ©Einstein College of Engineering