Real Time Monitoring of Long Slender Shaft by Distributed-Lumped Modeling Techniques

The aim of this paper is to determine the stress levels at the end of a long slender shaft such as a drilling assembly used in the oil or gas industry using a mathematical model in real-time. The torsional deflection experienced by this type of drilling shaft (about 4 KM length and 20 cm diameter hollow shaft with a thickness of 1 cm) can only be determined using a distributed modeling technique. The main objective of this project is to calculate angular velocity and torque at the end of the shaft by TLM method and also analyzing of the behavior of the system by transient response. The obtained result is compared with lumped modeling technique the importance of these results will be evident only after the mentioned comparison. Two systems have different transient responses and in this project because of the length of the shaft transient response is very important.

Authors:

• Sina Babadi
• K. M. Ebrahimi

Keywords:

• Distributed Lumped modeling
• Lumped modeling
• Drill string
• Angular Velocity
• Torque.

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