Sudden strong current generated by an eddy in the eastern part of Wakasa Bay, Japan

Waste water treatment by industry usually uses chemicals that may lead to additional environmental pollution load. On the other hand, water demand increases and environmental regulations regarding waste water disposal requirements that apply more stringent. It is necessary for waste treatment technique that accommodate this requirement. Electrocoagulation process is a technique of wastewater treatment that has been chosen because the technique is environmentally friendly. This paper will review some of the research or application electrocoagulation process which is conducted on industrial waste water. Types of industrial waste water that is to be reviewed include: industries batik, sarongs, textiles, palm oil, slaughterhouses, food, leather tanning, laundry, pulp and paper. Overview reviewed in this research include the waste water treatment process in several processing variations such as: change in time, electricity and kind of electrodes. The results of the research with electrocoagulation process in the industry are the removal efficiency of TSS, COD, BOD5, Chrome, phosphate, surfactants, color turbidity influenced by several factors including time, strong current, voltage, distance and type of electrode and pH. The results of the study with electrocoagulation process in the industry is the removal efficiency of TSS, COD, BOD5, chromium, phosphate, surfactant, turbidity color that are influenced by several factors including time, strong current, voltage, distance and type of electrode and pH. It is hoped the information presented in this article can be a reference for similar research for the improvement of research on the process ektrokoagulasi.Key words: elektrocoagulation, removal eficiency, environmental friendly

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SIMULATION OF NEARSHORE WAVES AND CURRENTS ALONG SALALAH COAST (OMAN) DURING THE TROPICAL CYCLONE ARB01

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.21610/conferencearticle_58b43151d336a ◽

2017 ◽

Author(s):

AbdAlla M. AbdAlla ◽

Abkar A. Iraqi ◽

Magdy M. Farag ◽

...

Keyword(s):

Tropical Cyclone ◽

Domain Boundary ◽

Circulation Model ◽

Shielding Effect ◽

Strong Current ◽

Waves And Currents ◽

Wave Heights ◽

Nearshore Waves ◽

Flood Period ◽

Significant Wave Heights

Sea level and wave data at Salalah coast (Oman) were used to simulate nearshore waves and current during the tropical cyclone ARB01 (9 May2002). STWAVE model (Steady State Spectral Wave) was applied for nearshore wave simulation, while M2D model ((Two-Dimensional Depth Averaged circulation model) was used to simulate nearshore current. The results of simulations (taking into account the mutual effects of both current and waves) showed that: The significant wave heights generally decrease from about 6m at the domain boundary to about 1 m close to the coast. The wave heights during the ebb period were higher than that during the flood period by about 1.5m. Along Salalah coast, higher waves were found along the eastern side of the domain. This is because the shielding effect of breakwater, which protect the western part of the coast from high waves. Relatively Strong current with values up to 1.5 ms-1 were found in the nearshore region during both ebb and flood periods. The M2D model results also showed cyclonic circulations during these periods which help in the renewal of harbor waters. Generally, the model results showed good agreements with observations in the investigated area.

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MHD heat pipes for imposition of a strong current into high temperature liquid metals

Magnetohydrodynamics ◽

10.22364/mhd.37.1-2.7 ◽

2001 ◽

Vol 37 (1-2) ◽

pp. 55-61

Keyword(s):

High Temperature ◽

Liquid Metals ◽

Heat Pipes ◽

Strong Current ◽

Temperature Liquid

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Effects of magnetic perturbations and radiation on the runaway avalanche

Journal of Plasma Physics ◽

10.1017/s0022377820001592 ◽

2021 ◽

Vol 87 (2) ◽

Author(s):

P. Svensson ◽

O. Embreus ◽

S. L. Newton ◽

K. Särkimäki ◽

O. Vallhagen ◽

...

Keyword(s):

Growth Rate ◽

Runaway Electrons ◽

Plasma Parameters ◽

Perturbative Approach ◽

Efficient Simulation ◽

Strong Current ◽

Magnetic Perturbations ◽

Space Dynamics ◽

Stochastic Magnetic Fields ◽

Mitigation Methods

The electron runaway phenomenon in plasmas depends sensitively on the momentum- space dynamics. However, efficient simulation of the global evolution of systems involving runaway electrons typically requires a reduced fluid description. This is needed, for example, in the design of essential runaway mitigation methods for tokamaks. In this paper, we present a method to include the effect of momentum-dependent spatial transport in the runaway avalanche growth rate. We quantify the reduction of the growth rate in the presence of electron diffusion in stochastic magnetic fields and show that the spatial transport can raise the effective critical electric field. Using a perturbative approach, we derive a set of equations that allows treatment of the effect of spatial transport on runaway dynamics in the presence of radial variation in plasma parameters. This is then used to demonstrate the effect of spatial transport in current quench simulations for ITER-like plasmas with massive material injection. We find that in scenarios with sufficiently slow current quench, owing to moderate impurity and deuterium injection, the presence of magnetic perturbations reduces the final runaway current considerably. Perturbations localised at the edge are not effective in suppressing the runaways, unless the runaway generation is off-axis, in which case they may lead to formation of strong current sheets at the interface of the confined and perturbed regions.

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Multicore structures and the splitting and merging of eddies in global oceans from satellite altimeter data

10.5194/os-2018-96 ◽

2018 ◽

Author(s):

Wei Cui ◽

Wei Wang ◽

Jie Zhang ◽

Jungang Yang

Keyword(s):

Intermediate Stage ◽

Altimeter Data ◽

Western Boundary ◽

Mean Flow ◽

Sea Level Anomalies ◽

Strong Current ◽

A Cell ◽

Circumpolar Current ◽

Overlap Ratio ◽

Global Oceans

Abstract. This study investigated the statistics of eddy splitting and merging in the global oceans based on 23 years’ altimetry data. Multicore structures were identified using an improved threshold-free closed-contour algorithm of sea surface height. Splitting and merging events were discerned from continuous time series maps of sea level anomalies. Multicore structures represent an intermediate stage in the process of eddy evolution, similar to the generation of multiple nuclei in a cell as a preparatory phase for cell division. Generally, splitting or merging events can change substantially (by a factor of two or more) the eddy scale, amplitude, and eddy kinetic energy. Specifically, merging (splitting) generally causes an increase (decrease) of eddy properties. Multicore eddies were found to tend to split into two eddies with different intensities. Similarly, eddy merging is not an interaction of two equal-intensity eddies, and that it tends to manifest as a strong eddy merging with a weaker one. A hybrid tracking strategy based on the eddy overlap ratio, considering both multicore and single-core eddies, was used to confirm splitting and merging events globally. The census revealed that eddy splitting and merging do not always occur most frequently in eddy-rich regions, e.g., their frequencies of occurrence in the Antarctic Circumpolar Current and western boundary currents were found obviously higher than mid-latitude regions (20°–35°) north and south. Eddy splitting and merging are caused primarily by an unstable configuration of multicore structures due to obvious current– or eddy–topography interaction, strong current variation, and eddy–mean flow interaction.

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