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The drill string vibrations can create harmful effects on drilling performance because they generate the stick-slip phenomenon which reduces the quality of drilling and decreases the penetration rate and may affect the robustness of the designed controller. For this reason, it is necessary to carefully test the different rock-bit contact models and analyze their influences on system stability in order to mitigate the vibrations. The purpose of this paper is to investigate the effects of rock-bit interaction on high-frequency stick-slip vibration severity in rotary drilling systems.

The main objective of this study is an overview of the influence of the rock-bit interaction models on the bit dynamics. A total of three models have been considered, and the drilling parameters have been varied in order to study the reliability of the models. Moreover, a comparison between these models has allowed the determination of the most reliable function for stick-slip phenomenon.

The torsional model with three degrees of freedom has been considered in order to highlight the effectiveness of the comparative study. Based on the obtained results, it has been concluded that the rock-bit interaction model has big influences on the response of the rotary drilling system. Therefore, it is recommended to consider the results of this study in order to design and implement a robust control system to mitigate harmful vibrations; the practical implementation of this model can be advantageous in designing a smart rotary drilling system.

Many rock-bit functions have been proposed in the literature, but no study has been dedicated to compare them; this is the main contribution of this study. Moreover, a case study of harmonic torsional vibrations analysis has been carried out in well-A, which is located in an Algerian hydrocarbons field, the indices of vibrations detection are given with their preventions.

This paper gives a bibliographical review of the finite element modelling and simulation of indentation testing from the theoretical as well as practical points of view. The bibliography lists references to papers, conference proceedings and theses/dissertations that were published between 1990 and 2002. At the end of this paper, 509 references are listed dealing with subjects such as, fundamental relations and modelling in indentation testing, identification of mechanical properties for specific materials, fracture mechanics problems in indentation, scaling relationship for indentation, indenter geometry and indentation testing.

Despite being the standard against which all other offshore work sites are compared, the male-dominated work culture of the Gulf of Mexico has received little attention from social scientists. Drawing on the literature on women and work in the United States, on women in the U.S. South, in the military, and in the oil field, and on interviews with hundreds of individuals this paper explores the roles of women in the development and maintenance of the offshore oil and gas industry in southern Louisiana.