1. Shawn Robinson
Exchanged ideas with: MeaganSaylors, Andres Ramos
Rotor Dynamics – Experiment #5
MEEN 4220 Engineering Lab, Fall 2014
D a t e D ue : 1 0 / 2 4 / 1 4
D a t e R e c e i ve d:
G ra ding S c he me :
I. Formatting:
Maximum
Points
Score
Obtained
1. Text - organized according to guidelines 5
2. Figures & Tables – numbered and titled 5
3. Equations - numbered and terms explained 5
4. References & Appendices - numbered and titled 5
II. Writing:
1. Applicable material in each section 10
2. Organization of ideas 10
3. Clarity of writing 10
III. Technical Content:
1. Covered important points 10
2. Sample calculations 10
3. Error analysis 10
4. Correct interpretation of results 10
IV. Creativity 5
V. Conciseness 5
TOTAL:
Texas A&M University-Corpus Christi
School of Engineering and Computing Sciences
Mechanical Engineering & Engineering Technology

2. Objectives:
Evaluate experimentally and analytically the critical speed and perform balancing of a flexible
shaft rotor assembly.
Materials:
Procedure:
My lab class did not get to perform the lab experiment. This lab report will focus on the
calculations of the experiment.
1. Measure the location of the rotors along the shaft and the distance between bearings.
2. Measure the shaft diameter, and the thickness and diameter of each rotor. Calculate their masses
3.
3. For Young’s modulus of the shaft material E=207MPa, calculate the critical speeds of the rotor
assembly in RPM with and without neglecting the weight of the shaft
Results:

3. Deflection due to shaft
Deflection due to Disk (repeat 3x)
Data Analysis:
Compare the results and explain the differences between the experimentally determined and the
calculated critical speeds. Formulas were put into excel to calculate theoretical values. Equations used ae
in appendix B.
Table.1 – Disk 1 deflection
Table.3 – Disk 3 deflection
Table.2 – Disk 2 deflection

4. Error Analysis:
My deflection values were all around 1*E-5(m) in magnitude. My critical speed for the disk was
228.85 rpm, and 231.55rpm with the shaft deflection values. Because we didn’t get to do the
experiment we don’t have any values to compare with other than ballpark range answers.
Table.4 – Disk and max deflections
Table.7 – Critical speed calculations
Table.6 – deflections of Disk w/ Shaft
Table.5 –deflections of Disk w/o Shaft

5. Conclusion:
In conclusion, the critical speed and deflections for a shaft with weighted disk can be calculated.
This method can be used to balance cam shafts and other industrial equipment. We did not get to
perform the full experiment due to system malfunction.
References:
P.A. Simionescu, Class Notes, Texas A&M Corpus Christi, Fall 2014.
J.L. Meriam and L. G. Kraige, Engineering Mechanics: Dynamics, Wiley, 7th ed., 2012.
AppendixA – ExperimentI
Appendix B – Calculations