Loading...

Modeling and Control of Vibrations in Horizontal Drill String with Coupled Axial and Torsional Vibrations

Rajabali, Farid | 2018

670 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 51704 (08)
  4. University: Sharif University of Technology
  5. Department: Mechanical Engineering
  6. Advisor(s): Moradi, Hamed; Vossoughi, Gholamreza
  7. Abstract:
  8. Oil and natural gas today are one of the most important sources of human energy supply, so that crude oil Percentage and natural gas provide 25% of the world's energy. Until now, vertical drilling methods have been used to extract oil and gas. In recent years, due to vertical drilling constraints, for extraction and access to places that can not be achieved by vertical drilling, Horizontal drilling has been increased. In horizontal drilling, a variety of vibrations including longitudinal, torsional, and lateral take place. These vibrations, if not controlled, can damage the equipment and the drilling field, as well as reduce the efficiency of the drilling process and increase the process time. The objective of this project is to obtain axial and torsional vibration coupling equations for continuous system and analysis of vibrational modes in horizontal section of horizontal drilling (directional). Also, obtained equations that are continuous vibrations are discreted using the summation mode method, and then the stability of the horizontal drill string is investigated and, if necessary, controller designed to stabilize the system. In this project, the coefficient of friction was modeled stochastic to simulate the actual situation. At first, the controller was designed with eight inputs and then its inputs were reduced to four inputs. Finally PI controller designed that is more executable and common in industry. We used feedback linearization method and then pole placement method to design controller. For exposing controller performance, we considered uncertainty for parameters
  9. Keywords:
  10. Horizontal Drilling ; Dynamics Models ; Coupled Axial Torsional Vibrations ; Vibration Control ; Mode-Summation Method ; Controller Design

 Digital Object List

 Bookmark

No TOC