Quantifying the mass discharge rate of flashing two phase releases through simple holes to the atmosphere

2018 ◽  
Vol 37 (3) ◽  
pp. 382-396 ◽  
Author(s):  
Tom Spicer ◽  
Derek Miller
Author(s):  
Г.В. Ли ◽  
Е.В. Астрова ◽  
А.М. Румянцев

Anodes made of macroporous silicon were studied. The galvanostatic cyclic tests carried out in half-cells with a Li counter electrode in the mode, when charging capacity was limited by Q1 = 1000 mAh/g, showed that the inclusion into the test program of a modifying cycle with an increased time of electrochemical lithiation allows to increase the charge/discharge rate upon the returning back to the initial mode. To interpret the obtained results, a two-phase model with a sharp a-LixSi/c-Si boundary was used. The introduction of a larger amount of lithium during the modifying cycle leads to an increase in the thickness of the amorphous layer, within which the introduction and extraction of lithium in subsequent cycles occur at a higher rate.


2019 ◽  
Vol 14 (1) ◽  
pp. 27-39 ◽  
Author(s):  
Fukashi Maeno ◽  
Setsuya Nakada ◽  
Mitsuhiro Yoshimoto ◽  
Taketo Shimano ◽  
Natsumi Hokanishi ◽  
...  

Kelud Volcano is among the most active volcanoes in Indonesia, with repeated explosive eruptions throughout its history. Here, we reconstructed the relationship between the repose period and the cumulative volume of erupted material over the past 100 years and estimated the long-term magma discharge rate and future eruptive potential and hazards. Tephra data and eruption sequences described in historical documents were used to estimate the volume and mass discharge rate. The volumes of the 1901, 1919, 1951, 1966, 1990, and 2014 eruptions were estimated as 51–296 × 106m3. The mass discharge rates were estimated to be on the order of 107kg/s for the 1919, 1951, and 2014 eruptions and the order of 106kg/s for the 1966 and 1990 eruptions. Based on a linear relationship between the repose period and cumulative erupted mass, the long-term mass discharge rate was estimated as ∼ 1.5 × 1010kg/year, explaining the features of the larger eruptions (1919, 1951, and 2014) but not those of the smaller eruptions (1966 and 1990). This estimate is relatively high compared to other typical basaltic-andesitic subduction-zone volcanoes. This result provides important insights into the evolution of magmatic systems and prediction of future eruptions at Kelud Volcano.


Author(s):  
Yasser Nabavi ◽  
Sander M. Calisal ◽  
Ayhan Akinturk ◽  
Voytek Klaptocz

The purpose of the research was to find a relationship between the geometric characteristics of an opening on deck and the water discharge rate. This study is aimed at the stability of open deck ferries and fishing vessels. The effective parameters on the discharge rate are the beam, depth of the water collected on the deck, and the discharge gap height. In this study, CFD analyses for water discharge from a ship deck were conducted, and the commercial code FLUENT was used to conduct the simulations. A two dimensional unsteady 2nd order solver in time and space was used for the simulation. The two-phase free surface model was simulated by the Volume of Fluid (VOF) method. Using the water discharge, the instantaneous depth Froude number was calculated as a part of the non-dimensional simulation. The effect of geometric parameters on the water discharge rate was investigated by keeping two parameters fixed while changing the third parameter. For each parameter, three different values were evaluated and the comparisons of all the twenty seven possible combinations of the effective parameters were presented. Results were compared with the experimental results obtained earlier at UBC.


1999 ◽  
Vol 104 (B12) ◽  
pp. 29387-29400 ◽  
Author(s):  
Emily E. Brodsky ◽  
Hiroo Kanamori ◽  
Bradford Sturtevant

Particuology ◽  
2021 ◽  
Author(s):  
Quan Chen ◽  
Ran Li ◽  
Wengzheng Xiu ◽  
Vladimir Zivkovic ◽  
Hui Yang

Fluids ◽  
2021 ◽  
Vol 6 (8) ◽  
pp. 276
Author(s):  
Hideo Kawahara ◽  
Kazuhito Kudo ◽  
Koichiro Ogata

An unstable discharge rate occurs during dry fine powder discharge from a hopper because of the significant two-phase solid/gas interactions that occur in powder flows. In addition, the air bubble phenomenon may occur in a silo during fine powder discharge. In this study, we conducted experiments using a semi-conical dual-structure hopper, and examined the effects on the hopper internal flow structure, cavity fluid pressure, pressure inside the airtight cavity section, and the powder discharge rate when changes are made in the position of the supplied air injection port and the solenoid valve open/close timing. From the experimental results, it was confirmed that an appropriate pressure supply port position exists, and the change in expansion/contraction of the flexible container due to air vibration is determined by the balance between the amount of air inserted and the amount of air discharged, and does not affect the presence or absence of powder so much. Furthermore, as the pressure value in the airtight void is directly related to the change in the expansion and contraction of the flexible container, the maximum amplitude value of the pressure in the airtight void can be kept high and constant at the time of opening and closing the solenoid valve.


2016 ◽  
Vol 121 (8) ◽  
pp. 5679-5695 ◽  
Author(s):  
Gianfranco Vulpiani ◽  
Maurizio Ripepe ◽  
Sebastien Valade

Author(s):  
Conlain Kelly ◽  
Nicholas Olsen ◽  
Dan Negrut

Abstract This study describes the implementation of a granular dynamics solver designed to run on Graphics Processing Units (GPUs). The discussion concentrates on how the Discrete Element Method (DEM) has been mapped onto the GPU architecture, the software design decisions involved in the process, and the optimizations allowed by those decisions. This solver, called Chrono::Granular, has been developed as a standalone library that can interface with other dynamics engines via triangle mesh co-simulation. A scaling analysis of the code presented herein demonstrates linear scaling with problem sizes of over two billion degrees of freedom and closing in on one billion bodies. We conclude with a study of hourglass (or hopper) mass discharge rate which compares the solver to experimental results and investigates a process for determining empirical coefficients of flow rate through simulation.


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