scholarly journals A numerical study of microparticle acoustophoresis driven by acoustic radiation forces and streaming-induced drag forces

Lab on a Chip ◽  
2012 ◽  
Vol 12 (22) ◽  
pp. 4617 ◽  
Author(s):  
Peter Barkholt Muller ◽  
Rune Barnkob ◽  
Mads Jakob Herring Jensen ◽  
Henrik Bruus
Keyword(s):  
Acoustic Radiation ◽  
Numerical Study ◽  
Drag Forces ◽  
Induced Drag ◽  
Radiation Forces

scholarly journals Acoustic radiation forces at liquid interfaces impact the performance of acoustophoresis

Lab on a Chip ◽  
2014 ◽  
Vol 14 (17) ◽  
pp. 3394-3400 ◽  
Author(s):  
Sameer Deshmukh ◽  
Zbigniew Brzozka ◽  
Thomas Laurell ◽  
Per Augustsson
Keyword(s):  
Acoustic Field ◽  
Speed Of Sound ◽  
Acoustic Radiation ◽  
Liquid Interfaces ◽  
Radiation Forces

Flow laminated liquids can relocate in a resonant acoustic field due to differences in density and speed of sound.

Prediction of Sand Production Through Porous Media: Mechanisms and Challenges to Optimising the Inefficiencies

2021 ◽  
Vol 18 (4) ◽  
pp. 45-52
Author(s):  
Wenhua Huang ◽  
Yan Huang ◽  
Juan Ren ◽  
Jinglong Jiang ◽  
Marischa Elveny
Keyword(s):  
Production Rate ◽  
Oil And Gas ◽  
Phenol Formaldehyde ◽  
Fundamental Issue ◽  
Sand Production ◽  
Drag Forces ◽  
Induced Drag ◽  
Porosity And Permeability ◽  
Production Conditions ◽  
Methods Of Control

One of the challenges facing drilling companies in the completion and production of oil and gas wells is sand production from the formation. The ability to predict sand production in the wells of a reservoir, to decide to use different methods of control is considered a fundamental issue. Therefore, analysis and study of sand production conditions and selecting the optimal drilling route before drilling wells are significant issues that are less considered. According to the findings of this study, due to the sand grains adhesion issue, saturation increase has caused to increase in the intermolecular uptake, and therefore moisture has been decreased. It leads to reduction in the sand production rate. Pressure increase has a direct relationship with the sand production rate due to increased induced drag forces. Moreover, phenol–formaldehyde resins provided an acceptable measurement as there are no significant changes in porosity and permeability.

A numerical study of the acoustic radiation due to eddy current-cryostat interactions

2017 ◽  
Vol 44 (6) ◽  
pp. 2196-2206 ◽  
Author(s):  
Yaohui Wang ◽  
Feng Liu ◽  
Xiaorong Zhou ◽  
Yu Li ◽  
Stuart Crozier
Keyword(s):  
Eddy Current ◽  
Acoustic Radiation ◽  
Numerical Study

Numerical Study in Wing Tip Vortex for a Modified Commercial Boeing Aircraft

2008 ◽  
Author(s):  
Ricardo Hernandez-Rivera ◽  
Abel Hernandez-Guerrero ◽  
Cuauhtemoc Rubio-Arana ◽  
Raul Lesso-Arroyo
Keyword(s):  
Numerical Study ◽  
Tip Vortex ◽  
Total Drag ◽  
The Core ◽  
Induced Drag ◽  
Wing Tip Vortex ◽  
Drag And Lift ◽  
Wing Tips ◽  
Wing Tip ◽  
Constant Mach Number

Recent studies have shown that the use of winglets in aircrafts wing tips have been able to reduce fuel consumption by reducing the lift-induced drag caused by wing tip vortex. This paper presents a 3-D numerical study to analyze the drag and lift forces, and the behavior of the vortexes generated in the wing tips from a modified commercial Boeing aircraft 767-300/ER. This type of aircraft does not contain winglets to control the wing tip vortex, therefore, the aerodynamic effects were analyzed adding two models of winglets to the wing tip. The first one is the vortex diffuser winglet and the second one is the tip fence winglet. The analyses were made for steady state and compressible flow, for a constant Mach number. The results show that the vortex diffuser winglet gives the best results, reducing the core velocity of the wing tip vortex up to 19%, the total drag force of the aircraft up to 3.6% and it leads to a lift increase of up to 2.4% with respect to the original aircraft without winglets.

scholarly journals Numerical Study of Hydrodynamic Forces for AFM Operations in Liquid

Scanning ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Tobias Berthold ◽  
Guenther Benstetter ◽  
Werner Frammelsberger ◽  
Rosana Rodríguez ◽  
Montserrat Nafría
Keyword(s):  
Drag Force ◽  
Numerical Study ◽  
Viscous Friction ◽  
Hydrodynamic Drag ◽  
Water Mixture ◽  
Ultrapure Water ◽  
Liquid Environment ◽  
Drag Forces ◽  
Organic Sample ◽  
Repulsive Forces

For advanced atomic force microscopy (AFM) investigation of chemical surface modifications or very soft organic sample surfaces, the AFM probe tip needs to be operated in a liquid environment because any attractive or repulsive forces influenced by the measurement environment could obscure molecular forces. Due to fluid properties, the mechanical behavior of the AFM cantilever is influenced by the hydrodynamic drag force due to viscous friction with the liquid. This study provides a numerical model based on computational fluid dynamics (CFD) and investigates the hydrodynamic drag forces for different cantilever geometries and varying fluid conditions for Peakforce Tapping (PFT) in liquids. The developed model was verified by comparing the predicted values with published results of other researchers and the findings confirmed that drag force dependence on tip speed is essentially linear in nature. We observed that triangular cantilever geometry provides significant lower drag forces than rectangular geometry and that short cantilever offers reduced flow resistance. The influence of different liquids such as ultrapure water or an ethanol-water mixture as well as a temperature induced variation of the drag force could be demonstrated. The acting forces are lowest in ultrapure water, whereas with increasing ethanol concentrations the drag forces increase.

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