scholarly journals Deformation and rupture of microcapsules flowing through constricted capillary

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Bruna C. Leopércio ◽  
Mariano Michelon ◽  
Marcio S. Carvalho
Keyword(s):  
Pressure Difference ◽  
Shell Thickness ◽  
Capillary Tube ◽  
Maximum Pressure ◽  
Target Delivery ◽  
Capsule Deformation ◽  
Internal Phase ◽  
Medical Diagnostic ◽  
Flow Through ◽  
Physiological Systems

AbstractThe dynamics of deformable microcapsules flowing through constricted channels is relevant in target delivery of chemicals in physiological systems, porous media, microfluidic medical diagnostic devices and many other applications. In some situations, the microcapsules need to sustain the stress they are subjected to as they flow through constricted channels and in others, the stress may be the rupture trigger used to release the internal content. We experimentally investigate the flow of monodispersed gellan gum microcapsules through a constricted capillary tube by measuring the evolution of the pressure difference and flow visualization. The maximum pressure difference and capsule deformation is obtained for capsules with different diameter and shell thickness. We map the conditions, e.g. diameter and shell thickness, at which the capsule membrane ruptures during the flow, releasing its internal phase.

scholarly journals Relationship and Mechanism Analysis of Soft-Melt Dropping Properties and Primary-Slag Formation Behaviors of the Mixed Burden in Increasing Lump Ore Ratio

Metals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1254 ◽  
Author(s):  
Yun-Fei Li ◽  
Zhi-Jun He ◽  
Wen-Long Zhan ◽  
Wei-Guo Kong ◽  
Peng Han ◽  
...  
Keyword(s):  
Pressure Difference ◽  
Cohesive Zone ◽  
Gas Permeability ◽  
Effective Means ◽  
Maximum Pressure ◽  
Slag Formation ◽  
Mechanism Analysis ◽  
Temperature Zone ◽  
Slag Properties ◽  
The Relationship

At present, cost reduction and environmental protection are the mainstream of blast furnace (BF) development and the high lump ore ratio is an effective means. Therefore, it is significant to explore the relationship and mechanism of burden soft-melt dropping and its primary-slag formation behaviors under increasing lump ore ratio. In this paper, the melt–drop test is carried out on the single ore and mixed burden, and obtained primary-slag properties are subjected to analysis. The experimental results show that the primary-slag of lump ore contains a large amount of FeO and SiO2, so it simply produces many low melting point compounds, which cause terrible soft-melt dropping properties and primary-slag formation behaviors. Notably, mixing with sinter and pellet can effectively improve both the properties. With the increase in lump ore ratio, the CaO in the primary-slag decreases, FeO and SiO2 increase, resulting in the melting temperature of the primary-slag sequentially decreasing and the cohesive zone moves to the low temperature zone. In addition, the maximum pressure difference increases, and the gas permeability deteriorates. Increasing the sinter ratio can overcome the defect of high lump ore ratio that can effectively improve the poor softening performance, melting performance and the position and thickness of the cohesive zone. However, because of the pulverization performance, the maximum pressure difference and gas permeability of the burden become worse.

Reverse Flow Pressure Limiting Aperture

2000 ◽  
Vol 6 (1) ◽  
pp. 21-30 ◽  
Author(s):  
Gerasimos D. Danilatos
Keyword(s):  
Pressure Difference ◽  
Gas Flow ◽  
Reverse Flow ◽  
Gas Jet ◽  
The Third ◽  
The Core ◽  
Annular Aperture ◽  
Flow Through ◽  
Flow Pressure ◽  
Gas Molecules

The reverse flow pressure limiting aperture is a device that creates and sustains a substantial gas pressure difference between two chambers connected via an aperture. The aperture is surrounded by an annular orifice leading to a third chamber. The third chamber is maintained at a relatively high pressure that forces gas to flow through the annular aperture into the first of said two chambers. The ensuing gas flow develops into a supersonic annular gas jet, the core of which is coaxial with the central aperture. A pumping action is created at the core of the jet and any gas molecules leaking through the aperture from the second chamber are entrained and forced into the first chamber, thus creating a substantial pressure difference between the first and second chamber.

The dispersion of matter in turbulent flow through a pipe

1954 ◽  
Vol 223 (1155) ◽  
pp. 446-468 ◽  
Keyword(s):  
Turbulent Flow ◽  
Capillary Tube ◽  
Resistance Coefficient ◽  
Mean Flow ◽  
Combined Action ◽  
Flow Through ◽  
The Mean ◽  
Coefficient Of Diffusion ◽  
Good Agreement ◽  
Made In

The dispersion of soluble matter introduced into a slow stream of solvent in a capillary tube can be described by means of a virtual coefficient of diffusion (Taylor 1953 a ) which represents the combined action of variation of velocity over the cross-section of the tube and molecluar diffusion in a radial direction. The analogous problem of dispersion in turbulent flow can be solved in the same way. In that case the virtual coefficient of diffusion K is found to be 10∙1 av * or K = 7∙14 aU √ γ . Here a is the radius of the pipe, U is the mean flow velocity, γ is the resistance coefficient and v * ‘friction velocity’. Experiments are described in which brine was injected into a straight 3/8 in. pipe and the conductivity recorded at a point downstream. The theoretical prediction was verified with both smooth and very rough pipes. A small amount of curvature was found to increase the dispersion greatly. When a fluid is forced into a pipe already full of another fluid with which it can mix, the interface spreads through a length S as it passes down the pipe. When the interface has moved through a distance X , theory leads to the formula S 2 = 437 aX ( v * / U ). Good agreement is found when this prediction is compared with experiments made in long pipe lines in America.

Investigation of flow through P[NIPAM/MMA] copolymer coated glass capillary tubes, and glass copolymer adhesion improvements with hydrofluoric acid etching

2010 ◽  
Vol 3 (1) ◽  
Author(s):  
R. Wiegmann ◽  
Y. Zhang ◽  
A. Yarin
Keyword(s):  
Fluid Flow ◽  
Hydrofluoric Acid ◽  
Microelectromechanical Systems ◽  
Capillary Tube ◽  
Acid Etching ◽  
Glass Capillary ◽  
Polymer Adhesion ◽  
Flow Through ◽  
Copolymer Poly ◽  
The Stability

This study aims to display the retention of the thermo-responsive properties of the copolymer poly(N-isopropyl acrylamide-methyl methacrylate) [P(NIPAM/MMA)] when coated on the inner diameter of a glass capillary tube, and to prove the stability of the copolymer coating when subjected to pressure driven fluid flow. The study shows that the fluid flow through such a capillary tube follows Hagen-Poiseuille flow. Furthermore, this study examines methods of improving polymer adhesion to glass by hydrofluoric acid etching. Such a coated tube system is applicable in drug delivery, self cleaning tubes, and microelectromechanical systems (MEMS).

scholarly journals Note on the Standard of Relative Viscosity, and on “Negative Viscosity.”

1906 ◽  
Vol 25 (1) ◽  
pp. 227-230 ◽  
Author(s):  
W. W. Taylor
Keyword(s):  
Capillary Tube ◽  
Relative Viscosity ◽  
Absolute Viscosity ◽  
Flow Through ◽  
The Absolute ◽  
Negative Viscosity ◽  
Image Position

The absolute viscosity calculated from the formula(where p = the pressure, t the time, r the radius, l the length of capillary, and v the volume of liquid), which connects the viscosity of a liquid with the rate of flow through a long capillary tube, is not often made use of, mainly on account of the difficulty of accurately determining some of the constants (r in particular).

scholarly journals Development of a PCR/LDR/Flow-Through Hybridization Assay Using a Capillary Tube, Probe DNA-Immobilized Magnetic Beads and Chemiluminescence Detection

2013 ◽  
Vol 29 (7) ◽  
pp. 689-695 ◽  
Author(s):  
Manami HOMMATSU ◽  
Hisamitsu OKAHASHI ◽  
Keisuke OHTA ◽  
Yusuke TAMAI ◽  
Kazuhiko TSUKAGOSHI ◽  
...  
Keyword(s):  
Magnetic Beads ◽  
Capillary Tube ◽  
Hybridization Assay ◽  
Chemiluminescence Detection ◽  
Flow Through

Poiseuille gas flow in the transition regime II. Application of the general theory

1967 ◽  
Vol 301 (1467) ◽  
pp. 401-409 ◽  
Keyword(s):  
Relaxation Time ◽  
Gas Flow ◽  
Capillary Tube ◽  
Collision Operator ◽  
Mean Free Path ◽  
Transition Regime ◽  
Tube Radius ◽  
Time Approximation ◽  
Relaxation Time Approximation ◽  
Flow Through

The general formulae given in the previous paper are investigated in detail using a simple relaxation-time approximation for the collision operator, and numerical results are obtained for the total gas flow through a capillary tube at various values of the ratio of tube radius to collision mean free path. For all values of this ratio, the results obtained agree with experiment to within about 2%.

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