A study of the glacier flow velocity in the Tianshan mountains based on high resolution SAR

2015 ◽  
Author(s):  
I.L. Zhao ◽  
J.H. Fan ◽  
R.Y. Wang ◽  
G. Liu
Keyword(s):  
High Resolution ◽  
Flow Velocity ◽  
Tianshan Mountains ◽  
Glacier Flow

Echo-planar high-resolution flow velocity mapping

1989 ◽  
Vol 12 (3) ◽  
pp. 316-327 ◽  
Author(s):  
D. N. Firmin ◽  
R. H. Klipstein ◽  
G. L. Hounsfield ◽  
M. P. Paley ◽  
D. B. Longmore
Keyword(s):  
High Resolution ◽  
Flow Velocity ◽  
Velocity Mapping ◽  
Echo Planar

High Resolution Particle Image Velocimetry and CH-PLIF Measurements and Analysis of a Shear Layer Stabilized Flame

2015 ◽  
Vol 138 (3) ◽  
Author(s):  
C. W. Foley ◽  
I. Chterev ◽  
J. Seitzman ◽  
T. Lieuwen
Keyword(s):  
Particle Image Velocimetry ◽  
High Resolution ◽  
Shear Layer ◽  
Flow Velocity ◽  
Particle Image ◽  
Flame Stabilization ◽  
Flow Conditions ◽  
Local Flow ◽  
Image Velocimetry ◽  
Flow Velocities

Understanding the mechanisms and physics of flame stabilization and blowoff of premixed flames is critical toward the design of high velocity combustion devices. In the high bulk flow velocity situation typical of practical combustors, the flame anchors in shear layers where the local flow velocities are much lower. Within the shear layer, fluid strain deformation rates are very high and the flame can be subjected to significant stretch levels. The main goal of this work was to characterize the flow and stretch conditions that a premixed flame experiences in a practical combustor geometry and to compare these values to calculated extinction values. High resolution, simultaneous particle image velocimetry (PIV) and planar laser induced fluorescence of CH radicals (CH-PLIF) measurements are used to capture the flame edge and near-field stabilization region. When approaching lean limit extinction conditions, we note characteristic changes in the stretch and flow conditions experienced by the flame. Most notably, the flame becomes less critically stretched when fuel/air ratio is decreased. However, at these lean conditions, the flame is subject to higher mean flow velocities at the edge, suggesting less favorable flow conditions are present at the attachment point of the flame as blowoff is approached. These measurements suggest that blowoff of the flame from the shear layer is not directly stretch extinction induced, but rather the result of an imbalance between the speed of the flame edge and local tangential flow velocity.

scholarly journals Measurement and modelling of high-resolution flow-velocity data under simulated rainfall on a low-slope sandy soil

2008 ◽  
Vol 348 (1-2) ◽  
pp. 1-12 ◽  
Author(s):  
L. Tatard ◽  
O. Planchon ◽  
J. Wainwright ◽  
G. Nord ◽  
D. Favis-Mortlock ◽  
...  
Keyword(s):  
High Resolution ◽  
Flow Velocity ◽  
Sandy Soil ◽  
Simulated Rainfall ◽  
Velocity Data

scholarly journals Deduction of Glacier Flow from the Distribution of Elongated Bubbles

1979 ◽  
Vol 24 (90) ◽  
pp. 457-467
Author(s):  
Masayoshi Nakawo
Keyword(s):  
Velocity Field ◽  
Distribution Pattern ◽  
Flow Velocity ◽  
Simple Shear ◽  
Air Bubbles ◽  
Glacier Surface ◽  
Passive Deformation ◽  
Measured Flow ◽  
Glacier Flow ◽  
Final Orientation

AbstractThe elongation of air bubbles discovered in a wide area of a glacier surface covered by supraglacial debris does not coincide with the direction of flow. When ice samples including elongated bubbles were subjected to simple-shear experiments, the elongated bubbles deformed passively with ice and their final orientation was a good indicator of the strain induced in the ice. Based on these experimental results, the strain and the velocity field of the glacier were deduced from the distribution pattern of the elongated bubbles. The results agreed with the measured flow velocity. The bubble foliation pattern could also be explained in terms of the passive deformation.

Denudation response of the Mediterranean Alpine Ranges to the Quaternary glacial cycles

2021 ◽  
Author(s):  
Pierre-Henri Blard ◽  
Stéphane Molliex ◽  
Apolline Mariotti ◽  
Julien Charreau ◽  
Gwenaël Jouet ◽  
...  
Keyword(s):  
High Resolution ◽  
Southern Alps ◽  
Special Focus ◽  
Glacial Cycles ◽  
Climatic Fluctuations ◽  
Denudation Rates ◽  
Original Dataset ◽  
Climatic Transition ◽  
The Mediterranean ◽  
Glacier Flow

<p>It is important to better understand how climatic fluctuations modified denudation, in particular during the large amplitude glacial cycles of the Quaternary, not only because denudation is thought to be a long-term climate pacer, but also because available denudation records are contradictory and sometimes underconstrained. To make progress on this question, we present here a compilation of <sup>10</sup>Be-derived denudation rates from 6 boreholes and cores drilled in offshore sediments from two alpine massifs of the Mediterranean Sea: Southern Alps (Var River) and Corsica (Golo River). This original dataset of 60 <sup>10</sup>Be samples from well-dated sedimentary archives documents at high resolution (1 kyr in some sections) the denudation variability over the last 3 million years of the alpine reliefs, with a special focus on the last five 100 kyr glacial cycles. Our new record brings two main results:</p><p>1) At the million years timescale, the appearance of the Quaternary glaciations at the Plio-Pleistocene transition (2.6 Ma) had a negligible impact on the mean <sup>10</sup>Be-derived denudation rates of Mediterranean Alpine reliefs. This observation is in good agreement with other <sup>10</sup>Be-denudation rates records from Asia (Tianshan and Himalaya) that report a limited impact of the Pleistocene climatic transition (Puchol et al., 2017; Charreau et al., 2020; Lenard et al., 2020), but at odds with other regions of the American Cordilleras, where tectonic may have played a role (Stock et al., 2004; Granger and Schaller, 2014).</p><p>2) At the glacial-interglacial cycles timescale, our high resolution <sup>10</sup>Be data over the last 500 kys reveal that glacial maxima enhanced denudation compared to interglacial periods. However, this impact is variable in space and time, different denudation responses being observed between Southern Alps and Corsica. This contrasted behavior appears to be controlled by the velocity of paleoglaciers. Glacier flow being determined by the combined impact of paleoclimate and basin reliefs, this mechanism is responsible for a non-linear response of denudation to glacier fluctuations. This may explain why glaciations had regionally variable impacts on denudation (Mariotti et al., 2021).</p><p><strong>References</strong></p><p>Charreau, J. et al. (2020) Basin Research. doi: 10.1111/bre.12511; Granger, D. E. and Schaller, M. (2014) Elements, doi: 10.2113/gselements.10.5.369; Lenard, S. J. P. et al. (2020) Nature Geoscience, doi: 10.1038/s41561-020-0585-2; Mariotti, A. et al. (2021) Nature Geoscience, doi: 10.1038/s41561-020-00672-2; Puchol, N. et al. (2017) Bulletin of the Geological Society of America, doi: 10.1130/B31475.1; Stock, G. M., et al. (2004) Geology, doi: 10.1130/G20197.1.</p>

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