Abstract This paperwork tried to simulate the combustion inside the naval engines using the newest computer methods and technologies with the result of a diverse and rich palette of solutions, extremely useful for the study and prediction of complex phenomena of the fuel combustion. The paperwork is contributing to the theoretical systematization of the area of interest bringing into attention a thoroughly inventory of the thermodynamic description of the phenomena which take place in the co...
Autori: Nicolae Buzbuchi, Liviu Constantin Stan, Daniela-Elena Mitu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25514

Fuel injection system, intake system and the geometric shape of combustion chamber are the three key factors to the fuel-air mixture and combustion process for diesel engine. long with the need of high power density in diesel engine, the pressure of intake is higher increasingly. Together with the effect of high pressure fuel injection, the fuel-air mixture and combustion process is hard to spread as usual. In this circumstance, the performance of power, heat efficiency and emission in diesel en...
Autori: Shang Yong, Liu Fu-Shui, Li Xiang-Ronghttp://www.ecozone.ro/reviste.php?RID=25704

This paper presents a study of the numerical simulation applied for unsymmetrical dimethylhrazine (UDMH) gas dispersion. This study considers an assumed UDMH store conditions and provides important data regarding the relation between the concentration distribution of UDMH and dispersion distance from the source based on the computation fluid dynamic (CFD) software FLUENT. The simulation results show that the ventilation vent and distance of dispersion play an important role in the concentration ...
Autori: Zhiyong Huang, Guofeng Jin, Xuanjun Wanghttp://www.ecozone.ro/reviste.php?RID=25712

AbstractThe hydrodynamics of two equipments from a surface water treatment pilot plant has been investigated through residence timedistribution (RTD) experiments using brine solution as tracer. Computational Fluid Dynamics (CFD) procedure, which isincreasingly utilized to study a wide variety of complex environmental fluid mechanics processes, was used to predict the flowpatterns and other properties of flowing fluids (e.g. velocity, concentration of species etc.). In this work, ANSYS Fluent 14....
Autori: Adina Pacala, Alain Liné, Alexandru-Dan Filep, Cosmina-Mariana Militaru, Teodor Todinca
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26030

AbstractThe ozone oxidation and disinfection stages constitute important technological phases in the modern systems of water treatment,both as unitary stages as integrated ones into systems that use advanced oxidation processes (AOP). More than half of thewater/ozone contact systems used nowadays in the water treatment plants are based on systems of contact in the bubble column.This work here aims at experimentally analysing, in terms of scale, a water-ozone contact system in the bubble column a...
Autori: Sorin Claudiu Ulinici
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26088

AbstractIn this article, hydrodynamic parameters and overall Oxygen mass transfer coefficient of petroleum based micro-emulsions in anairlift reactor were investigated. Four different petroleum-in-water micro-emulsion systems containing kerosene, heavy naphtha,light naphtha and diesel as oil based were used with concentrations of 3% and 7 % (v/v). The experimental data were supportedby simulation results obtained from the Computational Fluid Dynamics (CFD) method. The CFD was properly able to si...
Autori: Mostafa Keshavarz Moraveji
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26234

AbstractIn this paper, a study is conducted to assess the ability and the accuracy of a CFD approach concerning the behavior of a linearheat source positioned in a test room. Firstly, the main characteristics of our numerical model (mesh generation, turbulencemodel, near wall treatment, radiation model and boundary conditions) are presented after a briefly description of the test roomtaken into account. In addition, we show also the significance of these issues within our CFD approach. Furthermo...
Autori: Raluca Teodosiu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26467

This study presents an original method for waste heat recovery from exhaust flue gases using a heat pipe heat exchanger. For the proposed paper we analyzed using Autodesk Simulation CFD Software the operation of the originally designed heat pipe heat exchanger system in different hypothesis. For the complete analysis we realized a study case for a pizza restaurant building located in Iasi, Romania to prove the energy efficiency of the heat pipe heat exchanger unit. By applying our system, we ach...
Autori: Andrei Burlacu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27305

The global renewable energy share should reach and exceed 30% by 2030. Mini-scale hydropower installations are environmentally-friendly technologies, unlike large hydroelectric power plants that have certain drawbacks from the environmental point of view. A safe and clean solution is the cross-flow turbine, but the commercial types require a minimum head, usually captured by additional hydro-technical works that can also damage the environment. In this context, a very good solution could be a lo...
Autori: Daniela Popescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27343

In the current work, a numerical model for the prediction of temperature, air velocity, relative humidity and ammonia distribution released by sheep and goats manure inside a naturally ventilated livestock building is presented. Given that noteworthy amount of gaseous pollutants are emitted by the agricultural and animal husbandry activities, the study of the indoor microclimate is essential to be investigated for the healthy growth of the breeding livestock. The developed numerical model is sat...
Autori: Catherine Baxevanou
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27482

In this work, PM2.5 removal mechanism was explored to investigate PM2.5 collection efficiency under the influences of applied magnetic field and diffusion charging (the main charging mode for submicron particle). The proposed electrostatic precipitators (ESPs) mathematical model considered three-field interaction between fluid field, electromagnetic field and particle dynamic field. CFD software FLUENT was used to generate the simplified solid structure of the ESP. In numerical calculation, t...
Autori: Jian-Ping Zhang
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27667

Dust explosions are one of the main causes of mining disasters. To avoid them, it is important to understand how they are propagated. In the study reported here, computational fluid dynamics software was used to model a 3D diagonal pipe network then simulated a dust explosion at its inlet to examine its propagation characteristics. The initial conditions, boundary conditions and parameter settings were detailed description in the simulation to analyze possible propagation characteristics, assess...
Autori: Baichao Song
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28067

As CO2 concentration levels in the atmosphere are steadily reaching a point of no return, it is paramount that actions are taken towards mitigating emissions by improving the efficiency of existing processes. Sorption-enhanced water-gas shift (SEWGS) combines the water-gas shift reaction with in-situ adsorption of CO2 on potassium-promoted hydrotalcite (K-HTC). This enables a direct conversion of syngas into separate hot streams of H2 at feed pressure and CO2 at regeneration pressure, making th...
Autori: Vlad-Cristian Sandu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28149

A Computational Fluid Dynamics (ANSYS Fluent CFD) software was applied for the examination of a critical combined sewer section of Budapest (Hungary) sewer network. The critical part of the main branch is located at a combined sewer overflow (CSO) which is implying environmental risk for the receiving water body. The CFD simulations proved the anticipated disadvantageous hydrodynamic effects of the lateral inflow. A discrete phase model (DPM) was also applied to analyse the sediment transport...
Autori: Marcell Knolmar
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28183

Optimal evacuation routes are crucial to protect workers’ safety when accidental leakage of toxic gas occurs in chemical plants. However, the majority of route optimization focuses on the transport field and few on the evacuation routing optimization in chemical plants. This paper proposes a dynamic evacuation routing optimization method for chemical plants under toxic gas release scenarios. From the complete accident scenario set (CASS) built with wind fields and leakage sources, the leak...
Autori: Ying Liu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28336