Development of Image Analysis Tools to Evaluate In-Situ Evolution of the Grain Size Distribution in Sand Subjected to Breakage

2014 ◽  
pp. 253-258 ◽  
Author(s):  
Marios Gkiousas-Kapnisis ◽  
Edward Andò ◽  
Alessandro Tengattini ◽  
Itai Einav ◽  
Gioacchino Viggiani
Keyword(s):  
Grain Size ◽  
Image Analysis ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
Analysis Tools

scholarly journals Effect of Grain Size Distribution on Recrystallisation Kinetics in an Fe-30Ni Model Alloy

Metals ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 369 ◽  
Author(s):  
Mo Ji ◽  
Claire Davis ◽  
Martin Strangwood
Keyword(s):  
Grain Size ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
Cold Deformation ◽  
Avrami Exponent ◽  
Model Alloy ◽  
Avrami Parameter ◽  
In Situ Heating

This paper discusses the role of grain size distribution on the recrystallisation rates and Avrami values for a Fe-30 wt. % Ni steel, which was used as a model alloy retaining an austenitic structure to room temperature. Cold deformation was used to provide uniform macroscopic strain distributions (strains of 0.2 and 0.3), followed by recrystallisation during annealing at 850–950 °C. It was shown that the Avrami parameter was directly related to the grain size distribution, with a lower Avrami exponent being seen for a larger average and wider grain size distribution. A method to predict the Avrami exponent from the grain size distribution was proposed. In situ heating in an SEM with EBSD showed the recrystallisation kinetics to be affected by differences in stored energy and nucleation in the different grain sizes supporting the proposed relationship.

In-situ measurement of Ti-6Al-4V grain size distribution using laser-ultrasonic technique

2018 ◽  
Vol 154 ◽  
pp. 40-44 ◽  
Author(s):  
Feng Dong ◽  
Xiaochen Wang ◽  
Quan Yang ◽  
Huaqiang Liu ◽  
Dong Xu ◽  
...  
Keyword(s):  
Grain Size ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
In Situ Measurement ◽  
Ultrasonic Technique ◽  
Laser Ultrasonic

scholarly journals Linking flow-stream variability to grain size distribution of suspended sediment from a satellite-based analysis of the Tiber River plume (Tyrrhenian Sea)

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
J. Pitarch ◽  
F. Falcini ◽  
W. Nardin ◽  
V. E. Brando ◽  
A. Di Cicco ◽  
...  
Keyword(s):  
Grain Size ◽  
Size Distribution ◽  
Suspended Sediment ◽  
Grain Size Distribution ◽  
Flash Floods ◽  
Sandy Sediment ◽  
Tyrrhenian Sea ◽  
Tiber River ◽  
The Impact

AbstractSeveral coastal regions on Earth have been increasingly affected by intense, often catastrophic, flash floods that deliver significant amounts of sediment along shorelines. One of the critical questions related to the impact of these impulsive runoffs is “are flash floods more efficient in delivering non-cohesive sandy sediment along the coasts?” Here we relate flow stages (i.e., from erratic to persistent) to the grain size distribution of the suspended load, by performing a synergic analysis of in-situ river discharge and satellite-retrieved grain size distribution, from 2002 to 2014, covering the 2012 Tiber River (Italy) exceptional flood event. Our analysis shows novel and promising results regarding the capability of remote sensing in characterizing suspended sediment in terms of grain size distribution and reveals that erratic stages favour delivering of non-cohesive sandy sediment more than the persistent stages. This conclusion is supported by numerical simulations and is consistent with previous studies on suspended sediment rating curves.

scholarly journals Short Communication: Analysis of Grain Size Distribution through Image Analysis

2018 ◽  
Vol 09 (12) ◽  
pp. 2339-2346
Author(s):  
Dennis C. Gitz III ◽  
Jeffrey T. Baker ◽  
Paxton Payton ◽  
Zhanguo Xin ◽  
Robert J. Lascano
Keyword(s):  
Grain Size ◽  
Image Analysis ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
Short Communication ◽  
Communication Analysis

scholarly journals Image analysis for measuring the size stratification in sand–gravel laboratory experiments

2014 ◽  
Vol 2 (1) ◽  
pp. 217-232 ◽  
Author(s):  
C. Orrú ◽  
V. Chavarrías ◽  
W. S. J. Uijttewaal ◽  
A. Blom
Keyword(s):  
Grain Size ◽  
Image Analysis ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
Measurement Method ◽  
Laboratory Experiments ◽  
Size Fraction ◽  
Sediment Layer ◽  
Areal Fraction ◽  
Sediment Layers

Abstract. Measurements of spatial and temporal changes in the grain-size distribution of the bed surface and substrate are crucial to improving the modelling of sediment transport and associated grain-size selective processes. We present three complementary techniques to determine such variations in the grain-size distribution of the bed surface in sand–gravel laboratory experiments, as well as the resulting size stratification: (1) particle colouring, (2) removal of sediment layers, and (3) image analysis. The resulting stratification measurement method was evaluated in two sets of experiments. In both sets three grain-size fractions within the range of coarse sand to fine gravel were painted in different colours. Sediment layers are removed using a wet vacuum cleaner. Subsequently areal images are taken of the surface of each layer. The areal fraction content, that is, the relative presence of each size fraction over the bed surface, is determined using a colour segmentation algorithm which provides the areal fraction content of a specific colour (i.e. grain size) covering the bed surface. Particle colouring is not only beneficial to this type of image analysis but also to the observation and understanding of grain-size selective processes. The size stratification based on areal fractions is measured with sufficient accuracy. Other advantages of the proposed size stratification measurement method are (a) rapid collection and processing of a large amount of data, (b) a very high spatial density of information on the grain-size distribution, (c) the lack of disturbances to the bed surface, (d) only minor disturbances to the substrate due to the removal of sediment layers, and (e) the possibility to return a sediment layer to its original elevation and continue the flume experiment. The areal fractions are converted into volumetric fractions using an existing conversion model.

scholarly journals Effect of grain size distribution on Raman analyses and the consequences for in situ planetary missions

2013 ◽  
Vol 44 (6) ◽  
pp. 916-925 ◽  
Author(s):  
F. Foucher ◽  
G. Lopez-Reyes ◽  
N. Bost ◽  
F. Rull-Perez ◽  
P. Rüßmann ◽  
...  
Keyword(s):  
Grain Size ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
Planetary Missions
Sign in / Sign up

Export Citation Format

Share Document