21005 Bubble Nucleation Behavior in High Viscous Fluid under Rapid Decompression Conditions

2010 ◽  
Vol 2010.16 (0) ◽  
pp. 339-340
Author(s):  
Hideaki ASAI ◽  
Akiko KANEKO ◽  
Yutaka ABE
Keyword(s):  
Viscous Fluid ◽  
Bubble Nucleation ◽  
Nucleation Behavior ◽  
Rapid Decompression ◽  
High Viscous Fluid

scholarly journals Bubble Forming Behavior of High Viscous Fluid under Rapid Decompression

2008 ◽  
Vol 28 (5) ◽  
pp. 27-32
Author(s):  
Hitoshi FUJII ◽  
Akiko FUJIWARA ◽  
Nobuyuki WAKABAYASHI ◽  
Yutaka ABE
Keyword(s):  
Viscous Fluid ◽  
Rapid Decompression ◽  
High Viscous Fluid

Bubbles and element clusters in rock melts: A chicken and egg problem

2021 ◽  
Author(s):  
Renelle Dubosq ◽  
Pia Pleše ◽  
Brian Langelier ◽  
Baptiste Gault ◽  
David Schneider
Keyword(s):  
Heterogeneous Nucleation ◽  
Homogeneous Nucleation ◽  
Growth Dynamics ◽  
Gas Bubbles ◽  
Atom Probe ◽  
Bubble Nucleation ◽  
Interface Element ◽  
Rich Cluster ◽  
Heterogeneous Distribution ◽  
Rapid Decompression

<p>The nucleation and growth dynamics of gas bubbles and crystals play a vital function in determining the eruptive behaviour of a magma. Their rate and relative timing, among other factors, are controlled by the magma’s ascent rate. Investigating the kinetics of decompression-induced degassing and crystallization processes can thus give us insight into the rheology of magmas. For example, the rapid decompression of magmas inhibits microlite crystallization and bubble nucleation during ascent leading to crystallization and degassing at shallow levels. This results in a drastic increase in viscosity and an over pressured system, which can lead to violent eruptions. Although many experiments and numerical simulations of magma decompression have been carried out, nascent and initial bubble nucleation remain poorly understood. It is widely accepted that there are two ways bubbles can nucleate within a melt: heterogeneous (on a pre-existing surface) and homogeneous nucleation (within the melt), where homogeneous nucleation requires a higher volatile supersaturation. It has since been tentatively suggested that homogeneous nucleation is simply a variety of heterogeneous nucleation where nucleation occurs on the surface of submicroscopic crystals. However, evidence of these crystals is equivocal. Thus, we have combined novel 2D and 3D structural and chemical microscopy techniques including scanning transmission electron microscopy (STEM), electron energy-loss spectroscopy (EELS) mapping, and atom probe tomography (APT) to investigate the presence of sub-nanometer scale chemical heterogeneities in the vicinity of gas bubbles within an experimental andesitic melt. The combined STEM and EELS data reveal a heterogeneous distribution of bubbles within the melt ranging between 20-100 nm in diameter, some of which have Fe and/or Ca element clusters at the bubble-melt interface. Element clusters enriched in Fe, Ca, and Na are also observed heterogeneously distributed within the melt. The reconstructed APT data reveals bubbles as low ionic density regions overlain by a Na-, Ca-, and K-rich cluster and heterogeneously distributed Fe clusters within the bulk of the melt. Based on these observations, our data demonstrate the existence of nano-scale chemical heterogeneities within the melt and at the bubble-melt interface of bubbles that were previously interpreted to be nucleated homogeneously within the melt, therefore contributing to the proposed hypothesis that homogeneous nucleation could in fact be a variety of heterogeneous nucleation. These results highlight the need to redefine homogeneous nucleation and revisit whether bubbles or crystals occur first within volcanic melts. </p>

802 Basic Study on Damping Characteristic for Coaxial Circular Cylindrical Damper using High Viscous Fluid

2013 ◽  
Vol 2013.88 (0) ◽  
pp. _8-20_
Author(s):  
Naoto Nishimatsu ◽  
Tomohiro Ito ◽  
Atsuhiko Shintani ◽  
Chihiro Nakagawa
Keyword(s):  
Viscous Fluid ◽  
Basic Study ◽  
High Viscous Fluid

scholarly journals Two-phase fluid flow in geometric packing

2015 ◽  
Vol 373 (2056) ◽  
pp. 20150111 ◽  
Author(s):  
Aureliano Sancho S. Paiva ◽  
Rafael S. Oliveira ◽  
Roberto F. S. Andrade
Keyword(s):  
Viscous Fluid ◽  
Volume Fraction ◽  
Equations Of Motion ◽  
Two Phase ◽  
Ansys Fluent ◽  
Injection Speed ◽  
Complex Dependence ◽  
Complete Set ◽  
High Viscous Fluid ◽  
Phase Fluid

We investigate how a plug of obstacles inside a two-dimensional channel affects the drainage of high viscous fluid (oil) when the channel is invaded by a less viscous fluid (water). The plug consists of an Apollonian packing with, at most, 17 circles of different sizes, which is intended to model an inhomogeneous porous region. The work aims to quantify the amount of retained oil in the region where the flow is influenced by the packing. The investigation, carried out with the help of the computational fluid dynamics package ANSYS-FLUENT , is based on the integration of the complete set of equations of motion. The study considers the effect of both the injection speed and the number and size of obstacles, which directly affects the porosity of the system. The results indicate a complex dependence in the fraction of retained oil on the velocity and geometric parameters. The regions where the oil remains trapped is very sensitive to the number of circles and their size, which influence in different ways the porosity of the system. Nevertheless, at low values of Reynolds and capillary numbers Re <4 and n c ≃10 −5 , the overall expected result that the volume fraction of oil retained decreases with increasing porosity is recovered. A direct relationship between the injection speed and the fraction of oil is also obtained.

Research of non-contact measurement for high viscous fluid falling film thickness on spherical series surface

Measurement ◽  
2017 ◽  
Vol 101 ◽  
pp. 1-8 ◽  
Author(s):  
Yongxin Yu ◽  
Ling Ma ◽  
Hongyu Ye ◽  
Yizhong Zheng ◽  
Yuzhen Ma
Keyword(s):  
Viscous Fluid ◽  
Film Thickness ◽  
Falling Film ◽  
Contact Measurement ◽  
High Viscous Fluid
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