Hello folks,
I have been assigned to work on the vibrations of drill string suddenly and I am having some problems because I am not a mechanical engineer so I am not used to this work. The main purpose of this study is to estimate the dominant behavior of the types of vibration (axial, lateral and torsional) in a certain range of natural frequency.
So far, I have built a simple model using ANSYS and I have gotten some values of natural frequencies using different stiffness of the spring. Now the problem I am having is to validate if these spring stiffness are the real life stiffness or not. To make it simple, I have to find some physical ranges of rock stiffness or drilling stiffness of real life values and compare it with the spring stiffness I used in the simulation so that I can get the range of stiffness that is used in real life. From there, I can obtain the natural frequencies in that range and create a map to study the dominant behaviors of types of vibrations. I have been looking around on the web trying to find some physical ranges of drilling rock stiffness but no luck.
Any ideas on where to find some possible physical values of drilling stiffness / rock stiffness ?
Your help is very much appreciated. Thank you.
I have been assigned to work on the vibrations of drill string suddenly and I am having some problems because I am not a mechanical engineer so I am not used to this work. The main purpose of this study is to estimate the dominant behavior of the types of vibration (axial, lateral and torsional) in a certain range of natural frequency.
So far, I have built a simple model using ANSYS and I have gotten some values of natural frequencies using different stiffness of the spring. Now the problem I am having is to validate if these spring stiffness are the real life stiffness or not. To make it simple, I have to find some physical ranges of rock stiffness or drilling stiffness of real life values and compare it with the spring stiffness I used in the simulation so that I can get the range of stiffness that is used in real life. From there, I can obtain the natural frequencies in that range and create a map to study the dominant behaviors of types of vibrations. I have been looking around on the web trying to find some physical ranges of drilling rock stiffness but no luck.
Any ideas on where to find some possible physical values of drilling stiffness / rock stiffness ?
Your help is very much appreciated. Thank you.