Nonlinearity and Spectrum Analysis of Drill Strings with Component Mass Unbalance
نویسندگان
چکیده
This paper analyses the non linear properties exhibited by a drill string system under various un balanced mass conditions. The drill string is affected by continuous friction in the form of drill bit and well bore hole interactions. This paper proves the origin of limit cycling and increase of non linearity with increase in speed of the drilling in the presence of friction. The spectrum of the frequency response is also studied to detect the presence of vibration abnormalities arising during the drilling process. Keywords—Drill strings, Nonlinear, Spectrum analysis, Unbalanced mass
منابع مشابه
Drill string Vibration Modeling Including Coupling Effects
Abstract: The governing equations of motion for a drill string considering coupling between axial, lateral and torsional vibrations are obtained using a Lagrangian approach. The result leads to a set of non-linear equations with time varying coefficients. A fully coupled model for axial, lateral, and torsional vibrations of drill strings is presented. The bit/formation interactions are assumed ...
متن کاملEffects of Impeller Gap on Rotor Vibration in a High Speed Centrifugal Compressor: A Numerical and Experimental Analysis (TECHNICAL NOTE)
Centrifugal compressors produce high pressure ratio and rotate at speeds. So, a tiny unbalance can produce severe vibration. In this paper, effects of impeller gap on rotor vibration in a high speed centrifugal compressor is investigated. For this purpose, a numerical and experimental analysis are carried out. The moving reference frame method in FLUENT software is used for modeling of geometri...
متن کاملVoltage Equalization of DC Link capacitors in a CHB-Based PET under the Unbalance Voltage Conditions
The unbalance currents injection by power electronic transformers in order to improve the unbalance voltage conditions of the network causes an imbalanced voltage in the DC link capacitors and creates an active powers inequality in the different phases. In this paper, the proposed control structure independently controls the active power of each phase by modifying the power angle between the vo...
متن کاملEffects of Geometric Nonlinearity on Stress Analysis in Large Amplitude Vibration of thin Circular Functionally Graded Plates With Rigid Core
Abstract In this paper , the nonlinear the nonlinear free and forced axisymmetric vibration of a thin circular functionally graded plate with rigid core is formulated in terms of von-Karman’s dynamic equation , and a semi-analytical approach is developed.Functionally graded material (FGM) properties vary through the thickness of the plate.FGM s are spatial composites within which material prop...
متن کاملDynamics of nonlinear rectangular plates subjected to an orbiting mass based on shear deformation plate theory
In this paper, transverse and longitudinal vibration of nonlinear plate under exciting of orbiting mass is considered based on first-order shear deformation theory. The nonlinear governing equation of motion are discretized by the finite element method in combination with Newmark’s time integration scheme under von Karman strain-displacement assumptions. For validation of method and formulation...
متن کامل