Application of the new multi-component suspension model for skin-factor evaluating on the wells equipped with gravel packs

2018 ◽  
pp. 63-67 ◽  
Author(s):  
M.M. Khasanov ◽  
◽  
K.E. Lezhnev ◽  
V.D. Pashkin ◽  
A.P. Roshchektaev ◽  
...  
Keyword(s):  
Skin Factor ◽  
Suspension Model

Proposal for a full-body suspension model for osteopenia induction

2016 ◽  
Author(s):  
Alvaro Penoni ◽  
Gabriela Yanagihara ◽  
Jacqueline Tida ◽  
Brigida Brancaleon ◽  
Joao Paulo Issa ◽  
...  
Keyword(s):  
Suspension Model ◽  
Full Body

NON-ADDITIVE SKIN-FACTOR IN CASE OF A FORMATION COMPLEX DAMAGE

2019 ◽  
pp. 36-38
Author(s):  
M.V. Zaitsev ◽  
◽  
N.N. Mikhailov ◽  
Keyword(s):  
Skin Factor

A comparison of different models of passive seat suspensions

2021 ◽  
pp. 095440702199092
Author(s):  
Raj Desai ◽  
Anirban Guha ◽  
P. Seshu
Keyword(s):  
Human Body ◽  
Separate Analysis ◽  
Vehicle Model ◽  
Human Body Model ◽  
Human Comfort ◽  
Vehicle Handling ◽  
Seat Suspension ◽  
Handling Characteristics ◽  
Suspension Model ◽  
Suspension Models

Long duration exposure to vehicle induced vibration causes various ailments to humans. Amongst the various components of the human-vehicle system, the seat suspension plays a major role in determining the level of vibration transferred to humans. However, optimising the suspension for maximising human comfort leads to poor vehicle handling characteristics. Thus, predicting human comfort through various seat suspension models is a widely researched topic. However, the appropriate seat suspension model to be used has not been identified so far. Neither has any prior work reported integrating models of all the components necessary for this analysis, namely human body, cushion, seat suspension and vehicle chassis, each with the appropriate level of complexity. This work uses a two-dimensional 12 DoF seated human body model with inclined backrest support, a nonlinear cushion model, a seat suspension model and a full vehicle model. Two kinds of road profiles – one with random roughness and one with a bump – have been used. It then compares the performance of five different seat suspension models based on a number of human comfort related parameters (seat to head transmissibility, suspension travel, seat acceleration, cushion contact force and head acceleration in both vertical and fore-aft directions) and vehicle handling parameters (vertical, rolling and pitching acceleration of chassis). The results clearly show the superiority of the configuration which involves a spring parallel to an inclined multi-stage damper. A separate analysis was also done to judge whether the integration of the vehicle model (with its associated complication) was necessary for this analysis. A comparison of the human body’s internal forces, moments, acceleration, and absorbed power with and without the vehicle model clearly indicates the need of using the former.

scholarly journals Composite adaptive backstepping controller design and the energy calculation for active suspension system

2021 ◽  
Vol 104 (2) ◽  
pp. 003685042110105
Author(s):  
Xiaoyu Su ◽  
Bin Lin ◽  
Shuai Liu
Keyword(s):  
Adaptive Algorithm ◽  
Power Calculation ◽  
Calculation Formula ◽  
Adaptive Backstepping ◽  
Adaptive Law ◽  
Car Suspension ◽  
Backstepping Controller ◽  
Suspension Model ◽  
Storage Characteristics ◽  
Adaptive Backstepping Controller

The half-car suspension has the coupling of pitch angle and front and rear suspension. Especially when the suspension model has a series of uncertainties, the traditional linear control method is difficult to be applied to the half-car suspension model. At present, there is no systematic method to solve the suspension power. According to the energy storage characteristics of the elastic components of the suspension, the power calculation formula is proposed in this paper. This paper proposes a composite adaptive backstepping control scheme for the half-car active suspension systems. In this method, the correlation information between the output error and the parameter estimation error is used to construct the adaptive law. According to the energy storage characteristics of the elastic components of the suspension, the power calculation formula is introduced. The compound adaptive law and the ordinary adaptive law have good disturbance suppression, both of which can solve the pitching angle problem of the semi-car suspension, but the algorithm of the compound adaptive law is superior in effect. In terms of vehicle comfort, the algorithm of the general adaptive law can achieve stability quickly, but compared with the composite adaptive law, its peak value and jitter are higher, while the algorithm of the composite adaptive law is relatively gentle and has better adaptability to human body. In terms of vehicle handling, both control algorithms can maintain driving safety under road excitation, and the compound adaptive algorithm appears to have more advantages. Compared with the traditional adaptive algorithm, the power consumption of the composite adaptive algorithm is relatively lower than that of the former in the whole process. The simulation results show that the ride comfort, operating stability and safety of the vehicle can be effectively improved by the composite adaptive backstepping controller, and the composite adaptive algorithm is more energy-saving than the conventional adaptive algorithm based on projection operator.

Migration and Settling of Particulates in Filled Epoxies

2003 ◽  
Author(s):  
Lisa Mondy ◽  
Rekha Rao ◽  
Eric Lindgren ◽  
Amy Sun ◽  
Robert Lagasse ◽  
...  
Keyword(s):  
Particle Concentration ◽  
Particle Migration ◽  
Polymerization Reaction ◽  
Temperature Dependent ◽  
Filled Polymers ◽  
Post Test ◽  
Manufacturing Applications ◽  
Microscopy Data ◽  
Suspension Model ◽  
Epoxy Systems

Manufacturing applications for filled polymers include encapsulation of microelectronics and injection molding of composite parts. Predictive tools for simulating these manufacturing processes require knowledge of time- and temperature-dependent rheology of the polymer as well as information about local particle concentration. The overall system rheology is highly dependent on the particle concentration. The local particle concentration can change due to gravity, convection and shear-induced migration. For the epoxy systems of interest, an extent of reaction can be used to track the degree of cure. We couple the curing model with a diffusive flux suspension model [Zhang and Acrivos 1994] to determine the particle migration. This results in a generalized Newtonian model that has viscosity as a function of temperature, cure and concentration. Using this model, we examine settling of the particulate phase in both flowing and quiescent curing systems. We focus on settling in molds and flow in wide-gap counter-rotating cylinders. The heat transfer, including the exothermic polymerization reaction, must be modeled to achieve accurate results. The model is validated with temperature measurements and post-test microscopy data. Particle concentration is determined with x-ray microfocus visualization or confocal microscopy. Agreement between the simulations and experimental results is fair.

Analysis, Design, and Optimization of High Speed Vehicle Suspensions Using State Variable Techniques

1974 ◽  
Vol 96 (2) ◽  
pp. 193-203 ◽  
Author(s):  
J. K. Hedrick ◽  
G. F. Billington ◽  
D. A. Dreesbach
Keyword(s):  
High Speed ◽  
Optimization Problems ◽  
Vertical Plane ◽  
Computer Application ◽  
Vehicle Suspension ◽  
State Variables ◽  
State Variable ◽  
Suspension Parameters ◽  
Suspension Model ◽  
High Speed Vehicle

This article applies state variable techniques to high speed vehicle suspension design. When a reasonably complex suspension model is treated, the greater adaptability of state variable techniques to digital computer application makes it more attractive than the commonly used integral transform method. A vehicle suspension model is developed, state variable techniques are applied, numerical methods are presented, and, finally, an optimization algorithm is chosen to select suspension parameters. A fairly complete bibliography is included in each of these areas. The state variable technique is illustrated in the solution of two suspension optimization problems. First, the vertical plane suspension of a high speed vehicle subject to guideway and aerodynamic inputs will be analyzed. The vehicle model, including primary and secondary suspension systems, and subject to both heave and pitch motions, has thirteen state variables. Second, the horizontal plane suspension of a high speed vehicle subject to guideway and lateral aerodynamic inputs is analyzed. This model also has thirteen state variables. The suspension parameters of both these models are optimized. Numerical results are presented for a representative vehicle, showing time response, mean square values, optimized suspension parameters, system eigenvalues, and acceleration spectral densities.

High-Resolution and Multimaterial Fracture Productivity Calculator for the Successful Design of Channel Fracturing Jobs

2021 ◽  
Author(s):  
Dimitry Chuprakov ◽  
Ludmila Belyakova ◽  
Ivan Glaznev ◽  
Aleksandra Peshcherenko
Keyword(s):  
High Resolution ◽  
Effective Conductivity ◽  
Productivity Index ◽  
Hydraulic Fractures ◽  
Total Production ◽  
Fracture Conductivity ◽  
Hindered Settling ◽  
Accurate Evaluation ◽  
Skin Factor ◽  
Fracture Closure

Abstract We developed a high-resolution fracture productivity calculator to enable fast and accurate evaluation of hydraulic fractures modeled using a fine-scale 2D simulation of material placement. Using an example of channel fracturing treatments, we show how the productivity index, effective fracture conductivity, and skin factor are sensitive to variations in pumping schedule design and pulsing strategy. We perform fracturing simulations using an advanced high-resolution multiphysics model that includes coupled 2D hydrodynamics with geomechanics (pseudo-3D, or P3D, model), 2D transport of materials with tracking temperature exposure history, in-situ kinetics, and a hindered settling model, which includes the effect of fibers. For all simulated fracturing treatments, we accurately solve a problem of 3D planar fracture closure on heterogenous spatial distribution of solids, estimate 2D profiles of fracture width and stresses applied to proppants, and, as a result, obtain the complex and heterogenous shape of fracture conductivity with highly conductive cells owing to the presence of channels. Then, we also evaluate reservoir fluid inflows from a reservoir to fracture walls and further along a fracture to limited-size wellbore perforations. Solution of a productivity problem at the finest scale allows us to accurately evaluate key productivity characteristics: productivity index, dimensional and dimensionless effective conductivity, skin factor, and folds of increase, as well as the total production rate at any day and for any pressure drawdown in a well during well production life. We develop a workflow to understand how productivity of a fracture depends on variation of the pumping schedule and facilitate taking appropriate decisions about the best job design. The presented workflow gives insight into how new computationally efficient methods can enable fast, convenient, and accurate evaluation of the material placement design for maximum production with cost-saving channel fracturing technology.

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