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A Literature Review of Approaches for Stick-Slip Vibration Suppression in Oilwell Drillstring

open access: yesAdvances in Mechanical Engineering, 2014
Stick-slip vibration presents one of the main problems in the quality of drilling performance limiting tool life and productivity. This type of vibration can be suppressed by means of many approaches, such as varying parameters and use of control tools ...
Xiaohua Zhu, Liping Tang, Qiming Yang
doaj   +1 more source

Vibration and Control Characteristics of Downhole Drill String System

open access: yesShiyou jixie, 2022
Stick slip vibration seriously affects the life of drill string system,prolongs the drilling cycle,and endangers the safety of staff.In order to solve the problem of stick slip vibration caused by linear torque load and friction load in drilling ...
Ma Sunan   +6 more
doaj  

On the formation of limit cycle of the friction-induced stick-slip vibration in oilwell drillstring

open access: yesPetroleum, 2015
In this paper, the stick-slip vibration in oilwell drillstring is studied. The drilling system is modelled as a lumped-parameter torsional pendulum and the interaction between the drill bit and the rock is treated as Coulomb friction.
Xiaohua Zhu, Liping Tang
doaj   +1 more source

Estimation of the normal contact stiffness for frictional interface in sticking and sliding conditions [PDF]

open access: yes, 2019
Modeling of frictional contact systems with high accuracy needs the knowledge of several contact parameters, which are mainly related to the local phenomena at the contact interfaces and affect the complex dynamics of mechanical systems in a prominent ...
Baillet, L.   +4 more
core   +1 more source

Induced and endogenous acoustic oscillations in granular faults

open access: yes, 2019
The frictional properties of disordered systems are affected by external perturbations. These perturbations usually weaken the system by reducing the macroscopic friction coefficient.
Ciamarra, M. Pica   +3 more
core   +1 more source

Triple correlation for detection of damage-related nonlinearities in composite structures [PDF]

open access: yes, 2015
Nonlinear effects in vibration responses are investigated for the undamaged composite plate and the composite plate with a delamination. The analysis is focused on higher harmonic generation in vibration responses for various excitation amplitude levels.
Aymerich, F.   +6 more
core   +2 more sources

On the influence of external stochastic excitation on linear oscillators with subcritical self-excitation applied to brake squeal [PDF]

open access: yes, 2019
A characteristic of linear systems with self-excitation is the occurrence of non-normal modes. Because of this non-normality, there may be a significant growth in the vibration amplitude at the beginning of the transient process even in the case of ...
Gräbner, Nils   +3 more
core   +1 more source

Study on the Influence Factors Upon the Propensity to Stick-Slip Phenomenon During Vehicle Start-Up Process

open access: yesIEEE Access, 2020
The vibration caused by the friction characteristic of the clutch during the vehicle start-up process has an impact on driveline torsional oscillation.
Dongyang Wang   +4 more
doaj   +1 more source

Electrical Conductivities of Conductors, Semiconductors, and Their Mixtures at Elevated Temperatures

open access: yesAdvanced Engineering Materials, EarlyView.
This article presents a comprehensive review of temperature‐dependent electrical conductivity data for multiple material classes at elevated temperatures, highlighting a persistent conductivity gap between metals and semiconductors in the range of 102$\left(10\right)^{2}$– 107$\left(10\right)^{7}$ S/m. Metal–ceramic irregular metamaterials are proposed
Valentina Torres Nieto, Marcia A. Cooper
wiley   +1 more source

Directed transport of polymer drops on vibrating superhydrophobic substrates: A Molecular Dynamics study

open access: yes, 2013
Using Molecular Dynamics simulations of a coarse-grained polymer liquid we investigate the transport of droplets on asymmetrically structured (saw-tooth shaped), vibrating substrates.
Müller, Marcus, Tretyakov, Nikita
core   +1 more source

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