scholarly journals Electroviscous Effects in Stationary Solid Phase Suspensions

Fluids ◽  
2021 ◽  
Vol 6 (2) ◽  
pp. 69
Author(s):  
Francisco J. Rubio-Hernández
Keyword(s):  
Solid Phase ◽  
Relative Size ◽  
Primary Effect ◽  
Rheological Parameters ◽  
Pressure Gradients ◽  
Electroviscous Effect ◽  
Research Fields ◽  
Specific Effects ◽  
Ionic Distribution ◽  
Solid Liquid Interface

Flowing through porous media is a matter of interest in different research fields such as medicine, engineering and science. The spontaneous appearance of ionic distribution at the solid liquid interface gives place to a reduction in the flow rate, which is generally named electroviscous effect. However, this should be differentiated in two more specific effects, the primary effect due to the distortion of ionic clouds, and the secondary effect due to the overlapping of ionic clouds. Theoretical and experimental works have not always been clearly conducted in order to separate both effects. Instead, they have been globally grouped. The purpose of this review is to revise theoretical and experimental bibliography on the electroviscous effect in stationary solid phase suspensions (porous plugs, membranes, microchannels, capillaries). The main conclusions of this brief revision are: (i) when ionic clouds are relatively small, it is possible to accept that only the primary effect is the cause for the apparent increase of the viscosity of the liquid phase when it is forced to flow relative to the stationary solid phase; (ii) although theory predicts a maximum for the variation of the overall electroviscous effect vs the relative size of the ionic cloud, it has been experimentally observed but not properly reasoned that its existence depends on the salt type; and (iii) it is necessary to justify why, if the fluid is non-Newtonian, electrokinetic parameters dominate the characteristics of the flow due to high pressure gradients, but the rheological parameters are more decisive when the flow is generated by low pressure gradients.

Crystallization of liquids in the vicinity of a solid

1981 ◽  
Vol 34 (1) ◽  
pp. 1
Author(s):  
JE Lane ◽  
TH Spurling
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Solid Phase ◽  
Adsorbed Layer ◽  
Liquid Interface ◽  
Spherically Symmetric ◽  
Present Evidence ◽  
Ensemble Monte Carlo ◽  
Solid Liquid Interface ◽  
Solid Liquid

We present evidence, gained from grand ensemble Monte Carlo simulations of the solid/liquid interface, that an adsorbed layer of spherically symmetric liquid particles can have a crystal-like structure even if the solid phase is structureless.

Microstructure Evolution of Ti-Al Peritectic System during the Initiated Stage of Directional Solidification

2007 ◽  
Vol 546-549 ◽  
pp. 1447-1450 ◽  
Author(s):  
Yan Qing Su ◽  
Chang Liu ◽  
Xin Zhong Li ◽  
Jing Jie Guo ◽  
Heng Zhi Fu
Keyword(s):  
Steady State ◽  
Directional Solidification ◽  
Microstructure Evolution ◽  
Aluminum Content ◽  
Solid Phase ◽  
Tial Alloys ◽  
Transient Stage ◽  
Set Up ◽  
Solid Liquid Interface ◽  
Solid Liquid

The microstructure evolution of Ti-Al peretectic system in transient stage and steady state in directional solidification was predicted via theoretical analysis. The solute distribution controlled by diffusion at and ahead the solid-liquid interface will determine whether the properitectic and peritectic phases can nucleate and grow ahead of the opposing solid phase. The formation of banding structure is possible in a certain composition range. At the steady state, a microstructure selection map was set up based on interface response function model. The microstructure of TiAl alloys with different aluminum content was studied with Bridgman directional solidification method. Some evidence in the experiment has been found to support the theoretical prediction.

Studies on Heat Transfer From a Vertical Cylinder, With or Without Fins, Embedded in a Solid Phase Change Medium

1985 ◽  
Vol 107 (1) ◽  
pp. 44-51 ◽  
Author(s):  
B. Kalhori ◽  
S. Ramadhyani
Keyword(s):  
Heat Transfer ◽  
Experimental Investigation ◽  
Natural Convection ◽  
Solid Phase ◽  
Vertical Cylinder ◽  
Interface Shape ◽  
Fusion Temperature ◽  
Total Heat Transfer ◽  
Solid Liquid Interface ◽  
Solid Liquid

An experimental investigation of melting and cyclic melting and freezing around a vertical cylinder is reported. The studies encompass two cases: a plain vertical cylinder, and a vertical cylinder with fins. In the melting studies, the total heat transfer from the cylinder was measured as a function of time. In addition, measurements have been made of the solid-liquid interface shape after various melting times. In these studies, the solid phase was initially isothermal and either at its fusion temperature or subcooled below the fusion point. The experiments reveal the important influence of natural convection in the liquid phase in both unfinned and finned situations. Subcooling of the solid phase is observed to strongly inhibit heat transfer in the unfinned situation. In the experiment on cyclic melting and freezing, subcooling of the solid phase is once again found to have an important effect on the unfinned situation. Heat transfer from the finned cylinder is much less affected by solid-phase subcooling. All the experiments were performed with 99 percent pure n-eicosane paraffin.

Ultra Fast In Situ X-Ray Micro-Tomography: Application to Solidification of Aluminium Alloys

2012 ◽  
Vol 706-709 ◽  
pp. 1713-1718 ◽  
Author(s):  
Luc Salvo ◽  
Marco Di Michiel ◽  
Mario Scheel ◽  
Pierre Lhuissier ◽  
B. Mireux ◽  
...  
Keyword(s):  
Solid Phase ◽  
Early Stage ◽  
Copper Alloys ◽  
Cmos Technology ◽  
Acquisition Time ◽  
X Ray ◽  
Research Fields ◽  
Wide Range ◽  
Micro Tomography

X-ray micro-tomography has been applied recently in a wide range of research fields (damage in materials, solidification …). Thanks to the high flux of synchrotrons and specific cameras the total time to acquire a scan was considerably reduced. The use of a specific camera based on CMOS technology allows dividing the acquisition time for a complete scan by a factor of 100. Therefore we have been able to perform in situ solidification of aluminium-copper alloys at high cooling rates (between 1 and 10°C/s) and we will show results concerning the evolution of the microstructure in 3D in the early stage of solidification, in particular the morphology of the solid phase and the kinetics of growth.

scholarly journals Direct numerical simulation of solidification with effects of density difference

2016 ◽  
Vol 38 (3) ◽  
pp. 193-204
Author(s):  
Vu Van Truong
Keyword(s):  
Stokes Equations ◽  
Solid Phase ◽  
Density Difference ◽  
Navier Stokes ◽  
Navier Stokes Equations ◽  
Front Tracking Method ◽  
Liquid Phases ◽  
Solidification Processes ◽  
Solid Liquid Interface ◽  
Effects Of Density

In this paper, direct numerical simulations are presented for solidification with the effects of density difference between the solid and liquid phases. A front-tracking method is used. The solidification front, i.e. the solid-liquid interface separating solid and liquid, is represented by connected elements that move on a rectangular and stationary grid. The Navier-Stokes equations are solved by a projection method on the entire domain including the solid phase. An indicator function reconstructed from the front information is used to set the velocities in the solid phase to zero, and thus to enforce the no-slip condition at the interface. The method is validated through comparisons with exact solutions for one- and two-dimensional problems. The method is then used to simulate the solidification processes with the effects of volume change due to density difference

Radar Icing Algorithm: Algorithm Description and Comparison with Aircraft Observations

2021 ◽  
Author(s):  
David J. Serke ◽  
Scott M. Ellis ◽  
Sarah A. Tessendorf ◽  
David E. Albo ◽  
John C. Hubbert ◽  
...  
Keyword(s):  
Solid Phase ◽  
Weather Prediction ◽  
Relative Size ◽  
Particle Diameter ◽  
Area Under The Curve ◽  
Mixed Phase ◽  
Small Drop ◽  
Large Drop ◽  
Statistical Measures ◽  
Research Aircraft

AbstractDetection of in-flight icing hazard is a priority of the aviation safety community. The ‘Radar Icing Algorithm’ (RadIA) has been developed to indicate the presence, phase, and relative size of supercooled drops. This paper provides an evaluation of RadIA via comparison to in-situ microphysical measurements collected with a research aircraft during the 2017 'Seeded and Natural Orographic Wintertime clouds: the Idaho Experiment' (SNOWIE) field campaign.RadIA uses Level 2 dual-polarization radar moments from operational National Weather Service WSR-88D radar and a numerical weather prediction model temperature profile as inputs. Moment membership functions are defined based on the results of previous studies, and fuzzy logic is used to combine the output of these functions to create a 0 to 1 interest for detecting small-drop, large-drop and mixed phase icing.Data from the 2D-S particle probe on board the University of Wyoming King Air aircraft were categorized as either liquid or solid phase water with a shape classification algorithm and binned by size. RadIA interest values from 17 cases were matched to statistical measures of the solid/liquid particle size distributions (such as maximum particle diameter) and values of LWC from research aircraft flights. Receiver Operating Characteristic Area Under the Curve (AUC) values for RadIA algorithms were 0.75 for large-drop, 0.73 for small-drop, and 0.83 for mixed-phase cases. RadIA is proven to be a valuable new capability for detecting the presence of in-flight icing hazards from ground-based precipitation radar.

Influence of vibration on grain size and degree of grain refinement in mild steel weldments

1993 ◽  
Vol 8 (9) ◽  
pp. 2228-2230 ◽  
Author(s):  
S.P. Tewari
Keyword(s):  
Grain Size ◽  
Mild Steel ◽  
Grain Refinement ◽  
Solid Phase ◽  
Steel Plates ◽  
Lower Amplitude ◽  
Experimental Findings ◽  
Solid Liquid Interface ◽  
Solid Liquid ◽  
Fast Removal

Mild steel plates were welded under stationary and dynamic (longitudinal and transverse vibration) conditions. The frequency and amplitude ranges selected were 0 Hz to 300 Hz and 0 μm to 30 μm, respectively. It has been observed on the basis of experimental findings that vibration, in general, reduces the grain size of the weldment, and this reduction is appreciable at a lower amplitude of vibration. This may be due to the lower energy required for nucleation of the solid phase. Fast removal of latent heat of solidification from the solid liquid interface plays a significant part in the grain refinement under vibration.

scholarly journals A liquid-phase two-site immunoradiometric assay for human prolactin

1984 ◽  
Vol 217 (1) ◽  
pp. 273-279 ◽  
Author(s):  
S C Hodgkinson ◽  
J Landon ◽  
P J Lowry
Keyword(s):  
Solid Phase ◽  
High Sensitivity ◽  
Immunoradiometric Assay ◽  
Specific Antibodies ◽  
Simultaneous Addition ◽  
Operating Range ◽  
Specific Effects ◽  
Rabbit Igg ◽  
Human Prolactin ◽  
Time Required

The development of a ‘two-site’ immunoradiometric assay for human prolactin (hPrl) is described. The assay is based on the addition of radio-iodinated sheep anti-hPrl immunoglobulin G (IgG) and rabbit anti-hPrl serum to standards and unknowns followed by 3 h incubation. The use of solid phase reagents was avoided in order to minimize non-specific effects and the time required for reactants to reach equilibrium. Instead, the separation of hPrl-bound and free labelled antibody is achieved by the addition of sheep anti-(rabbit IgG) serum which precipitates bound labelled antibody by complex formation with rabbit anti-hPrl antibodies which are also hPrl-bound. Varying the order of addition of specific antibodies had a pronounced effect on the ‘operating range’ and sensitivity of resultant assays. This was attributed to competition between labelled and unlabelled antibodies for binding sites on the hPrl molecule. The immunoradiometric assay employing ‘simultaneous addition’ of specific antibodies was compared to a ‘simultaneous addition’ hPrl radioimmunoassay developed using the same sheep antiserum as that used to prepare the radioiodinated sheep anti-hPrl IgG. This immunoradiometric assay is characterized by rapid equilibration of reactants, a wide ‘operating range’ (the precision of dose estimates was less than 10% over the range 8-10000 mU/l), and high sensitivity (2.6 mU/l, 13 pg). In contrast, the hPrl radioimmunoassay required an incubation of 18 h, demonstrated a much reduced ‘operating range’ (the precision of dose estimates was less than 10% only over the range 25-1500 mU/l) and reduced sensitivity (9.8 mU/l, 49 pg).

Transient Freezing of Liquids in Forced Flow Inside Circular Tubes

1969 ◽  
Vol 91 (3) ◽  
pp. 385-389 ◽  
Author(s):  
M. N. O¨zis¸ik ◽  
J. C. Mulligan
Keyword(s):  
Solid Phase ◽  
Freezing Temperature ◽  
Local Heat ◽  
Liquid Interface ◽  
Forced Flow ◽  
Transfer Rates ◽  
Tube Wall Temperature ◽  
Temperature Constant ◽  
Solid Liquid Interface ◽  
Solid Liquid

The transient freezing of a liquid flowing inside a circular tube is investigated analytically under the assumption of a constant tube wall temperature which is lower than the freezing temperature, constant properties, a slug-flow velocity profile and quasisteady state heat conduction in the solid phase. The variation of the local heat flux and the profile of the solid-liquid interface during freezing has been determined as a function of time and position along the tube. The analysis produced steadystate heat transfer rates and profiles for the solid-liquid interface which agreed well with experiments.

scholarly journals Pipe pressure of mining wet shot crete flowing in pipes

2021 ◽  
Vol 303 ◽  
pp. 01035
Author(s):  
Lianjun Chen ◽  
Xuekai Jiang ◽  
Guoming Liu ◽  
Xiangfei Cui
Keyword(s):  
Pressure Drop ◽  
Flow Rate ◽  
Solid Phase ◽  
Pressure Change ◽  
Rheological Parameters ◽  
Computational Formula ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Mix Proportion ◽  
Phase Pressure

In order to explore the pressure change law of mining wet shotcrete in pipes, the rheological model was built based on rheology principle, and the computational formula of rheological parameters of wet shotcrete was deduced with the linear regression. 100 m full-scale pipeline platform of wet shotcrete was designed and built to study the relationship of pressure and other factors including flow rate, water cement ratio, mix proportion, and pipe bends. Results show: pipe pressure increases with the increase in flow rate and declines with the increase in water-cement ratio, the pressure may fluctuate with a high water cement ratio which can cause cement overhydration and bleeding separation. It will be more beneficial to transport materials if the continuous grading and straight pipe were considered. According to the tests of mix proportion 1:1.5:2.25, the pressure drop is 0.032 MPa·m−1 and the bend pressure drop is 1.3 times higher than in the straight line. We also conclude that solid phase pressure is bigger than liquid phase pressure and they both decline along the pipe based on FLUENT simulation. Finally, the formula of on-way resistance used in mine production was deduced.

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