Numerical modelling of landslide-tsunami propagation in a wide range of idealised water body geometries

Phytoplankton from a part of the Shitalakhya river receiving effluents from a pharmaceutical industry have been studied. A total of 78 taxa were identified of which 14 belonged to Cyanophyceae, 11 Chlorophyceae, 20 Euglenophyceae and 33 Bacillariophyceae. The water body was mostly alkaline (6.6 - 8.0) and showed a wide range of variation in conductivity (135 - 4768 μS/cm), DO (anoxia to 15 mg/l), free- CO2 (3 - 29 mg/l), bicarbonate alkalinity (49 - 355 mg/l), BOD (8 - 1800 mg/l) at different locations. Pharmaceutical effluents appeared to affect diversity of phytoplankton. Three diatoms namely Fragilaria brevistriata Grun., F. construens (Ehr.) Grun. and Navicula oblonga Kütz. present in the area, are described as new for Bangladesh. Keywords: Phytoplankton; Pharmaceutical effluents; Shitalakhya River; Bangladesh DOI: 10.3329/bjb.v38i1.5127 Bangladesh J. Bot. 38(1): 77-85, 2009 (June)

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Modelling The Fire Performance of Structural Timber-Concrete Composite Floors

Journal of Structural Fire Engineering ◽

10.1260/2040-2317.5.2.113 ◽

2014 ◽

Vol 5 (2) ◽

pp. 113-124 ◽

Cited By ~ 2

Author(s):

James O'Neill ◽

Anthony Abu ◽

David Carradine ◽

Peter Moss ◽

Andrew Buchanan

Keyword(s):

Numerical Modelling ◽

Fire Resistance ◽

Experimental Testing ◽

Mechanical Analysis ◽

Fire Performance ◽

Finite Element Software ◽

Wide Range ◽

Floor Systems ◽

3D Numerical Modelling ◽

Full Scale Tests

This paper describes numerical modelling to predict the fire resistance of engineered timber-concrete composite floor systems. The paper describes 3D numerical modelling of the floor systems using finite element software, carried out as a sequential thermo-mechanical analysis. Experimental testing of these floor assemblies has also been undertaken to validate the models, with multiple full scale tests conducted to determine the failure mechanisms and assess fire damage to the system components. The final outcome of this research is the development of simplified design methods for calculating the fire resistance of a wide range of engineered timber floor systems, as part of a larger research project on multi-storey timber buildings.

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On the relation of bottom valley-type reservoir hydrocarbon carbon flux and hydrological structure of water body

Vestnik of Saint Petersburg University Earth Sciences ◽

10.21638/spbu07.2021.104 ◽

2021 ◽

Vol 66 (1) ◽

Author(s):

Diana V. Lomova ◽

◽

Maria G. Grechushnikova ◽

Ludmila E. Efimova ◽

Viktor A. Lomov ◽

...

Keyword(s):

Organic Matter ◽

Bottom Sediments ◽

Water Body ◽

Carbon Flux ◽

Weather Conditions ◽

Structure Of Water ◽

Hydrological Structure ◽

Wide Range ◽

Water Ecosystems ◽

Valley Type

Circulation of carbon in water bodies is fundamental process of nutriens cycle in water ecosystems. Carbon flux from bottom sediments is the less studied chain of this circulation nowdays. The aim of investigation was the study of HCO3 flux from bottom sediments in the valley-type reservoir and identification of their relation with hydrological structure of water body. Field works and laboratory experiments were fulfilled at Mozhaisk reservoir in 2017-2019. These years differed by weather conditions, level regime and stability of water masses. Hydrological surveys were fulfilled three times during summer period of each year. They included measuring of vertical distribution of hydrological characteristic and sampling of water and bottom sediments. The Kuznetsov-Romanenko tube method was used to study exchange processes. Hydrocarbonate carbon flux from sediments into the water may have a wide range (50-900 mgC/m2day). By comparison of HCO3 flux with hydrological structure it was revealed that in deep (>8 m) regions it depends on stratification and thickness of uniform hypolymnion, where seiches and compensation currents may promote transsedimentation from shallow places to flooded river bed. At the regions with depth <8 m hydrocarbonate carbon flux from sediments depends much more from autochthonic organic matter, produced by phytoplankton. The relationship of the HCO3 flux with the content of organic matter in the soil and its hygroscopic humidity is insignificant.

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Estimation of Evaporation Losses of Bunker LNG

World of Transport and Transportation ◽

10.30932/1992-3252-2020-18-84-106 ◽

2020 ◽

Vol 18 (3) ◽

pp. 84-106

Author(s):

O. V. Tarovik ◽

A. S. Reutsky ◽

A. G. Topazh

Keyword(s):

Natural Gas ◽

Numerical Modelling ◽

Transport Systems ◽

Computer Simulation Model ◽

Comprehensive Understanding ◽

Quantitative Estimates ◽

Wide Range ◽

Fuel Tanks ◽

Natural Gas Vehicles ◽

Thermodynamic Processes

Analysis of efficiency of transport systems using liquefied natural gas (LNG) as fuel is impossible without a comprehensive understanding of the volumes of fuel LNG losses from evaporation during main technological operations: transportation (storage), bunkering, and cool-down of fuel tanks. Despite active development of water and land natural gas vehicles, practical approaches for obtaining appropriate estimates in a wide range of characteristics of cargo tanks have not been previously published.The objective of this work is to analyze LNG losses in road, rail and ship tanks (with a capacity of up to 5600 m3), as well as in tank containers, provided that LNG is stored with an overpressure of about 5–7 atmospheres.In the work, numerical modelling was used as a method. The evaporation process of LNG is described using models of heat exchange between the liquid phase of LNG, its vapours, as well as a cargo tank and the external environment. This makes it possible to simulate the behaviour and phase transformations of LNG during its storage in a tank, as well as during main technological operations. Numerical modelling of thermodynamic processes during storage of LNG is performed using a computer simulation model implemented in AnyLogic environment. Quantitative estimates of LNG losses during bunkering and cool-down of fuel tanks were obtained based on analytical calculations.An analysis of sensitivity of the created models to various parameters, as well as massive numerical calculations, made it possible to construct regression relationships to determine LNG losses during operations under consideration. The obtained dependencies can be used to search for the most effective configurations of the system for low-tonnage LNG transportation, as well as to perform economic assessments of feasibility of using LNG as fuel for water and land transport.

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Development and numerical modelling of a novel UV/H2O2 rotating flow reactor for water treatment

Water Science & Technology ◽

10.2166/wst.2021.063 ◽

2021 ◽

Author(s):

Minghan Luo ◽

Wenjie Xu ◽

Taeseop Jeong

Keyword(s):

Numerical Modelling ◽

Uv Irradiation ◽

High Efficiency ◽

Flow Reactor ◽

Reaction Rates ◽

Photochemical Reactions ◽

Rotating Flow ◽

Flow Mode ◽

Oh Radicals ◽

Wide Range

Abstract The ultraviolet photochemical degradation process is widely applied in wastewater treatment due to its low cost, high efficiency and sustainability. In this study, a novel rotating flow reactor was developed for UV-initiated photochemical reactions. The reactor was run in a continuous flow mode, and the tangential installation of the inlet and outlet on the annular reactor improved reaction rates. Numerical modelling, which combined solute transport, radiation transfer and photochemical kinetic degradation processes, was conducted to evaluate improvement compared to current reactor designs. Methylene Blue (MB) decomposition efficiency from the modelling results and the experimental data agreed well with each other. The model results showed that a rotational motion of fluid was well developed inside the designed reactor for a wide range of inflow rates; the generation of ·OH radicals significantly depended on UV irradiation dose, and thus the degradation ratio of MB showed a strong correlation with the UV irradiation distribution. In addition, the comprehensive numerical modelling showed promising potential for the simulation of UV/H2O2 processes in rotating flow reactors.

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Numerical modelling of tsunami propagation with implications for sedimentation in ancient epicontinental seas: The Lower Jurassic Laurasian Seaway

Sedimentary Geology ◽

10.1016/j.sedgeo.2010.03.008 ◽

2010 ◽

Vol 228 (3-4) ◽

pp. 81-97 ◽

Cited By ~ 6

Author(s):

Andrew J. Mitchell ◽

Peter A. Allison ◽

Matthew D. Piggott ◽

Gerard J. Gorman ◽

Christopher C. Pain ◽

...

Keyword(s):

Numerical Modelling ◽

Lower Jurassic ◽

Tsunami Propagation

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MUFITS: A Universal Reservoir Simulator for Numerical Modelling, History Matching and Optimization of Multicomponent Flows in Porous Media

10.5194/egusphere-egu2020-11914 ◽

2020 ◽

Author(s):

Andrey Afanasyev ◽

Elena Vedeneeva ◽

Natalia Gorokhova

Keyword(s):

Carbon Dioxide ◽

Porous Media ◽

Numerical Modelling ◽

History Matching ◽

External Control ◽

Flows In Porous Media ◽

Reservoir Simulations ◽

Multicomponent Flows ◽

Wide Range ◽

Reservoir Simulator

The recent development of the academic reservoir simulator MUFITS aims its transformation to a universal software package that allows for (a) numerical modelling of non-isothermal multicomponent flows in porous media under wide range of pressures and temperatures, including under critical thermodynamic conditions, (b) history matching of non-isothermal reservoir models, and (c) optimization of thermohydrodynamic processes in porous media.The extended simulator capabilities for modelling of multicomponent flows includes a new fluid properties module for compositional and thermal reservoir simulations using different cubic equations of state (e.g. Peng-Robinson EoS). An extended library of hydrocarbons, carbon dioxide, nitrogen, water, and other components is built into the simulator, and additional components can be characterized and loaded into the library. An arbitrary number of components can be used in particular simulation. In order to simplify the module usage, the corresponding input data are made compatible with the petroleum industry standards. Unlike many other codes, MUFITS allows for compositional modelling of non-isothermal flows of fluids which properties are predicted with a cubic EoS.For improved history matching and optimization the simulator is supplied with an external Simulation Control Unit (SCU), which automatically changes certain parameters of the digital reservoir model and reads back the results of the simulations. An external control loop is implemented in SCU. At each iteration of the loop non-isothermal flow in a porous medium is simulated, and the simulation results are used for calculation of the objective function being minimized. In order to accelerate the history matching and optimization, the SCU can simultaneously (in parallel) run several reservoir simulations. The simulator is supplied with the build-in capabilities for the calculation of gravity changes and surface uplift/subsidence which measurements can also be automatically used in history matching.We complement the new developments with several application examples related to gas condensate fields exploration, carbon dioxide injection in depleted oil reservoirs and gas storages, and natural flows in deep geothermal systems.We acknowledge the funding from Russian Science Foundation under grant # 19-71-10051.

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