An Explicit Full-Range Settling Velocity Equation for Mud Flocs

2011 ◽  
Vol 81 (12) ◽  
pp. 921-934 ◽  
Author(s):  
K. Strom ◽  
A. Keyvani
Keyword(s):  
Settling Velocity ◽  
Full Range ◽  
Velocity Equation

Development of Elastic Drag Coefficient Model and Explicit Terminal Settling Velocity Equation for Particles in Viscoelastic Fluids

SPE Journal ◽  
2020 ◽  
Vol 25 (06) ◽  
pp. 2962-2983 ◽  
Author(s):  
Zhengming Xu ◽  
Xianzhi Song ◽  
Zhaopeng Zhu
Keyword(s):  
Drag Force ◽  
Shear Viscosity ◽  
Settling Velocity ◽  
Particle Diameter ◽  
Viscoelastic Fluids ◽  
Proppant Transport ◽  
Fluid Elasticity ◽  
Fracturing Fluids ◽  
Proposed Model ◽  
Velocity Equation

Summary Viscoelastic fluids are frequently used as drilling or fracturing fluids to enhance cuttings or proppant transport efficiency. The solid transport performance of these fluids largely depends on the settling behaviors of suspended particles. Different from viscoinelastic fluids, the elastic and viscous characteristics of viscoelastic fluids both affect particle settling behaviors. In this study, to separately quantify the contribution degrees of the shear viscosity and fluid elasticity on the terminal settling velocity, we decompose the total drag force into a viscous drag force and an elastic drag force. Based on the experimental data from the available literature, it is concluded that the elastic drag force is a function of the fluid elasticity, particle diameter, particle terminal settling velocity, and density difference between the fluid and particle. The formula for the elastic drag force is determined on the basis of the force analysis, and a relationship between the elastic drag coefficient and particle Reynolds number (Re) is developed. An explicit equation that directly predicts the terminal settling velocity in viscoelastic fluids is determined by correlating the dimensionless particle diameter and Re. To validate the proposed model, a total of 108 settling experiments in viscoelastic fluids are conducted. The absolute percentage error (APE) between the predicted and measured terminal settling velocities is 15.26%, which indicates that the proposed explicit terminal settling velocity equation can provide satisfactory prediction accuracy of the terminal settling velocity for particles in viscoelastic fluids. Furthermore, an illustrative example is provided to show that the proposed model can be used to calculate the required fluid elasticity to obtain the desired terminal settling velocity when the fluid shear viscosity is fixed. The proposed models are valid with a consistency index range of approximately 0.16 to 1.2 Pa⋅sn, flow behavior index range of approximately 0.282 to 0.579, an Re range of approximately 0.005 to 30, and a fluid relaxation time range of approximately 0.183 to 110 seconds. This study can help operators choose proper drilling/fracturing fluids to enhance the cuttings/proppant transport and maximize drilling/fracturing performance.

A new settling velocity equation for cohesive sediment based on experimental analysis

2018 ◽  
Vol 3 (2) ◽  
pp. 77-85
Author(s):  
Aisha Mhashhash ◽  
Bettina Bockelmann-Evans ◽  
Shunqi Pan
Keyword(s):  
Experimental Analysis ◽  
Settling Velocity ◽  
Cohesive Sediment ◽  
Velocity Equation

Time Block After Time Block

ASHA Leader ◽  
2013 ◽  
Vol 18 (8) ◽  
pp. 40-45 ◽  
Author(s):  
Judy Rudebusch ◽  
JoAnn Wiechmann
Keyword(s):  
Full Range ◽  
Time Block ◽  
School Based ◽  
Schedule Activity

To offer a full range of RTI and IEP services, school-based SLPs can schedule activity blocks rather than go student by student—here's how.

The Use of Neuroplastic Principles Affects the Swallow Motor Plan of a Patient in Severe Cognitive Decline: A Case Study

2016 ◽  
Vol 1 (15) ◽  
pp. 79-83
Author(s):  
Ed Bice ◽  
Kristine E. Galek
Keyword(s):  
Central Nervous System ◽  
Cognitive Decline ◽  
Full Range ◽  
Movement Speed ◽  
Positive Outcomes ◽  
Verbal Cues ◽  
Motor Plan ◽  
Bolus Size ◽  
The Central Nervous System

Dysphagia is common in patients with dementia. Dysphagia occurs as a result of changes in the sensory and motor function of the swallow (Easterling, 2007). It is known that the central nervous system can undergo experience-dependent plasticity, even in those individuals with dementia (Park & Bischof, 2013). The purpose of this study was to explore whether or not the use of neuroplastic principles would improve the swallow motor plan and produce positive outcomes of a patient in severe cognitive decline. The disordered swallow motor plan was manipulated by focusing on a neuroplastic principles of frequency (repetition), velocity of movement (speed of presentation), reversibility (Use it or Lose it), specificity and adaptation, intensity (bolus size), and salience (Crary & Carnaby-Mann, 2008). After five therapeutic sessions, the patient progressed from holding solids in her mouth with decreased swallow initiation to independently consuming a regular diet with full range of liquids with no oral retention and no verbal cues.

Further Validity of the Japanese Version of the Ten Item Personality Inventory (TIPI-J)

2014 ◽  
Vol 35 (4) ◽  
pp. 236-244 ◽  
Author(s):  
Atsushi Oshio ◽  
Shingo Abe ◽  
Pino Cutrone ◽  
Samuel D. Gosling
Keyword(s):  
Big Five ◽  
Content Validity ◽  
Structural Equation ◽  
English Language ◽  
Full Range ◽  
Reliability And Validity ◽  
Japanese Version ◽  
Personality Inventory ◽  
Equation Modeling ◽  
Big Five Personality

The Ten Item Personality Inventory (TIPI; Gosling, Rentfrow, & Swann, 2003 ) is a widely used very brief measure of the Big Five personality dimensions. Oshio, Abe, and Cutrone (2012) have developed a Japanese version of the TIPI (TIPI-J), which demonstrated acceptable levels of reliability and validity. Until now, all studies examining the validity of the TIPI-J have been conducted in the Japanese language; this reliance on a single language raises concerns about the instrument’s content validity because the instrument could demonstrate reliability (e.g., retest) and some forms of validity (e.g., convergent) but still not capture the full range of the dimensions as originally conceptualized in English. Therefore, to test the content validity of the Japanese TIPI with respect to the original Big Five formulation, we examine the convergence between scores on the TIPI-J and scores on the English-language Big Five Inventory (i.e., the BFI-E), an instrument specifically designed to optimize Big Five content coverage. Two-hundred and twenty-eight Japanese undergraduate students, who were all learning English, completed the two instruments. The results of correlation analyses and structural equation modeling demonstrate the theorized congruence between the TIPI-J and the BFI-E, supporting the content validity of the TIPI-J.

Body and Desire

2018 ◽  
Author(s):  
Raphael A. Cadenhead
Keyword(s):  
Full Range ◽  
The Body ◽  
Gregory Of Nyssa ◽  
The Past ◽  
Ethical Discourse ◽  
Sex And Sexuality ◽  
Diachronic Analysis

Although the reception of the Eastern father Gregory of Nyssa has varied over the centuries, the past few decades have witnessed a profound awakening of interest in his thought, particularly in relation to the contentious issues of gender, sex, and sexuality. The Body and Desire sets out to retrieve the full range of Gregory’s thinking on the challenges of the ascetic life through a diachronic analysis of his oeuvre. Exploring his understanding of the importance of bodily and spiritual maturation in the practices of contemplation and virtue, Raphael Cadenhead recovers the vital relevance of this vision of transformation for contemporary ethical discourse.

Numerical Simulation of Tire Sliding Events Involving Impacts with Holes and Bumps

1986 ◽  
Vol 14 (2) ◽  
pp. 125-136 ◽  
Author(s):  
Y. Nakajima ◽  
J. Padovan
Keyword(s):  
Numerical Simulation ◽  
Finite Element ◽  
Finite Element Simulation ◽  
Full Range ◽  
Arbitrary Geometry ◽  
Operating Environments ◽  
Element Simulation ◽  
Simulation Scheme

Abstract This paper extends the finite element simulation scheme to handle the problem of tires undergoing sliding (skidding) impact into obstructions. Since the inertial characteristics are handled by the algorithm developed, the full range of operating environments can be accommodated. This includes the treatment of impacts with holes and bumps of arbitrary geometry.

Methodological bases and practice of risk management of regional development (part 1)

2020 ◽  
Vol 18 (2) ◽  
pp. 114-126
Author(s):  
Valery V. Karpov ◽  
Anna G. Breusova ◽  
Anna A. Korableva
Keyword(s):  
Risk Management ◽  
Regional Development ◽  
Regional Economy ◽  
Full Range ◽  
Risk Identification ◽  
Territorial Development ◽  
Public Authorities ◽  
Strategic Risk ◽  
Risk Committee ◽  
State Programs

The article is devoted to the theoretical foundations and analysis of the experience of subjects of the Russian Federation in the field of regional development risk management. The article examines the concept of risk, its difference and relationship with the concepts of uncertainty, threat, danger, security and others. It is determined that dangers are constantly present in the regional economy. And risk, as a measurable uncertainty with multiple outcomes, for which the probability of occurrence of a risk event is calculated, is manifested as a result of the occurrence of a hazard. When comparing the concepts of risk and security, this means that the security of the regional economy is manifested in the ability to resist threats and manage risks, and not in the complete absence of dangers. It is revealed that ISO standards distinguish between the concepts of risk management and risk management. For further discussion, risk management is understood as a systematic approach to using the full range of mechanisms available to public authorities to reduce emerging risks and threats to the socio-economic development of the region. Further, the analysis of risk management in the practice of regional management on the example of the Omsk, Novosibirsk and Tyumen regions is carried out. The relevant tools in the activities of government bodies, such as territorial development strategies, state programs and projects, were identified, which allowed us to introduce a classification of risks with the allocation of strategic, tactical risks of territorial development and project management risks, among which there is a strategic level. The analysis of the implemented tools for compliance with the mandatory stages of risk management showed mainly the absence of risk identification, unified requirements for risk accounting and systematic risk management of regional development. Among the assessed regions, the Tyumen region has the best practices in terms of risk management. For a more detailed analysis authors highlighted the key institutional and instrumental elements of risk management such as risk committee, strategic risk map, risk register, action plan for risk management, and defined logical relationships between them.

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