Frequency Analysis of a rotating shaft

Aim

In this challenge, we will have to Model the image shown above in Solidworks to dimensions that you see fit and find out the critical frequencies of a rotating shaft.

Introduction

In this challenge, we will be working under the frequency simulation for a rotating shaft to find the critical frequency at which the part fails or the highest frequency until which the part withstands, this is done by the procedure given below ie firstly the model of a rotating shaft with mass at its center is drawn and then the boundary condition ie the fixtures are provided and the study is run, from the study, the results are calculated and the required values are estimated.

Basic theory on the simulation

Simulation is an easy-to-use portfolio of structural analysis tools that use Finite Element Analysis (FEA) to predict a product’s real-world physical behavior by virtually testing CAD models. The portfolio provides linear, non-linear static, and dynamic analysis capabilities. This is the explanation given for simulation by Solidworks, to make it into simple form simulation is nothing but the analysis of part, or a model in a real-life situation before it is made to test in real life, ie the product is tested and required results are obtained in the software itself and if any design changes to be made are done and the product is optimized by this simulation results.

Case setup

In this challenge, the case setup is kind of simple since we are doing a frequency study only the fixtures are made to be done and before which the modeling has to be done and the other procedures are given below in brief,

Modeling

This modeling process is made simple since the dimensions are left to us so that the model that we make fits the given image, and for this process, the front plane is selected and in which firstly the smaller dia shaft is drawn using a circle and extruded using midplane option to make sure that the mass is in center of the shaft.

https://drive.google.com/drive/folders/12xL7hN9NUKrZ19u9sTfPSNibtVn4Pvn-?usp=sharing

The above mentioned is the link for the part file.

Fixtures and Load applied

For this challenge the smaller dia face of the shaft is selected for fixture and a bearing fixture is provided and other parameters are left to default.

And for loading conditions, there are no-load conditions since this is a frequency analysis directly the mesh option is given and the simulation is run.

Mesh

Meshing is purely depended on the user ie if the user needs accurate results he can use a fine mesh and if not so he can use coarse mesh and in another hand, the coarse meshing doesn't take much time to solve the solution, but its inverse in the fine refinement of mesh it takes more time to compute results.

Plots

The first plot is the result of zero frequency, here the deformation is high at the center mass of the shaft, ie the deformation value is given as 0.31.

This below-given plot is the comparison of the two similar mode shape frequency analysis, this comparison is made in order to make things more clear since they both are with the same no of mode points but vibrating in different directions.

Firstly to look into X direction, the vibration of the shaft is in X direction the vibration causes a deformation value of 0.59, and also the mode shape value is 94 Hz.

This is also similar in Y-axis only the values change in decimal points.

From this, it is clearly known that the vibration limit for this mode shape is limited to 94Hz if exceeds above the shaft gets damaged.

This below-given plot is the comparison of the two similar mode shape frequency analysis, this comparison is made in order to make things more clear since they both are with the same no of mode points(3) but vibrating in different directions.

Firstly to look into X direction, the vibration of the shaft is in X direction the vibration causes a deformation value of 0.29, and also the mode shape value is 420 Hz.

This is also similar in Y-axis only the values change in decimal points.

From this, it is clearly known that the vibration limit for this mode shape is limited to 420Hz if exceeds above the shaft gets damaged.

And also it is noted that the larger value is plotted at the ends of the center mass in the center of the shaft which is clearly;y seen through the color contour given.

LIST OF RESONANT FREQUENCIES

Observation and the Conclusion

The above-mentioned table shows the Frequency(rad/sec) and Frequency(Hz),

For the first mode shape, the frequency is zero

For the second and third mode shape or mode points the vibration occurs in X, Y direction has similar values with few variations, however, the shaft fails for both the condition when the frequency exceeded above 94Hz.

For the third mode points ie 3 points the vibration is done in both X, Y directions and this also results in similar results with each other, and also the shaft fails or gets damages when the frequency increased above 420Hz.

NOTE*

In this challenge, I am unable to give name as suggested from your side ie RAHUL_frequency_analysis, due to some issue with my PC or my mail I am not sure of it, but still, I have given name as per ur suggestion for the folder, so please do kindly take this into account. Thank you