AbstractConsidering the importance of transfer phenomena in chemical engineering and environmental protection, in particular heat transfer modelling, numerical methods are applied to investigate the transient heat transfer inside an elliptic cylinder. The temperature of the surrounding medium was considered constant and equal to the temperature on the surface of the cylinder. The heat balance equation was solved numerically in elliptic coordinate system. The computations were focused on the infl...
Autori: Gheorghe Juncu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25269

AbstractIn this paper the results of surface water treatment process for drinking purpose are presented, using the microfiltrationultrafiltration process. The experimental studies were carried out using a microfiltration-ultrafiltration pilot plant and raw water from Bega River, Timisoara as feed. To assess process performance, the water quality, e.g., turbidity, total coliforms and hardness parameters were determined for two different operating regimes subjected to filtration time. A good effic...
Autori: Camelia Podaru, Cristian Danielescu, Florica Manea, Georgeta Burtica, Ilie Vlaicu, Viorel Patroescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25332

Temperature distribution in the vacuum directional solidification system influenced seriously on the impurities concentration andmicrostructure in Polycrystalline Silicon. In this study, a numerical model for the transient global heat transfer for directionsolidification process has been developed by the finite element method (FEM). A two-dimension numerical simulation fortemperature distribution of directional solidification process was carried out using software Multi-physics Comsol 3.5a. Ther...
Autori: Guoqiang Lv, Wenhui Ma, Hua Wang, Xiangyang Mei, Kuixian Weihttp://www.ecozone.ro/reviste.php?RID=25671

Abstract:An efficient conversion of kinetic energy of river waters into mechanical or electrical energy without building barrages isprovided by micro-hydropower stations. Increased efficiency is achieved by an optimum position of the blades withhydrodynamic profile. The formulation used to compute the hydrodynamic forces is an inviscid - boundary layer model. Microhydropowerstation provides kinetic energy conversion of river water into mechanical or electrical energy without buildingbarrages. In...
Autori: Anatol Sochireanu, Ion Bostan, Ion Dicusară, Nicolae Trifan, Oleg Ciobanu, Radu Ciobanu, Valeriu Dulgheru, Viorel Bostan
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25723

Abstract:The operation of solar air heat collectors consists in a sequence of transient regimes, being conditioned by the availability in timeof the solar resource. This paper presents the results of an experimental research on transient regimes of two types of solar air heatcollectors. The absorbers of the collectors have different configurations and are made of different materials. One collector is acommercial passage air collector with the absorber made of aluminum. The other collector is an ...
Autori: Adrian Ciocănea, Andrei Dragomirescu, Sanda Budea
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25731

Abstract:The concept of passive and low energy houses became fashionable in the last years and the European Parliament also initiated aproposal to build only near zero energy houses from 2018. The regulations already in force aim at low energy consumption (mostlikely influenced by the wide spreading of the �Passivhaus� concept in Europe) and by 2018 harmonized regulations andstandards will require the near zero energy building. According to the concept of the Energy Performance of Building D...
Autori: András Zöld, Tünde Kalmár
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25751

Abstract:The aim of this paper is to propose a set of thermal models for the regenerator by taking into account the time dependent heattransfer processes, and to combine them with the thermodynamic lumped description of the solar Stirling engine, accordingly torecent description.By using analytical and numerical methods, the optimum power of the engine is sought when various constrains (or not) areconsidered, particularly fixed heat transfer rate available at the source.A sensitivity analysis of...
Autori: Alexandru Dobrovicescu, Andreea Marin, Catalina Dobre, Georgiana Tirca-Dragomirescu, Michel Feidt, Monica Costea
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25767

Abstract In many industrial applications most of the solid particles are separated by size and for this purpose there are used the oscillating sieves. The separation process based on sieves is a complex one and it depends on several factors, such as the properties of solid particles submitted to the separation process and on the operating regimes of the separating equipment. We have studied the separation process of the behaviour of solid particles on a flat oscillating surface...
Autori: Ovidiu Bontas
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26134

AbstractThe South-to-North Water Diversion Project is a huge project to better utilize water resources available to China, especially forsolving the shortage of water resources in northern china. Increasing attention has been paid to the impact of the project on thegroundwater of water-receiving areas. Beijing is one of the important water-receiving areas of The Middle Route, and the waterwill be transferred into Beijing in 2014. The main objective of this study is to analyze the influence of S-...
Autori: Haizhen Xu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26222

Abstract Although in Lithuania artificial land drainage is a common water management practice, there are still concerns about its downstream hydrological effects. Due to the complexity of flow driving factors, the hydrological effect of drainage is very uncertain, making it difficult to determine its relative importance. Aiming to distinguish between the influence of drainage and other factors in this study, the extent of changes of twenty hydrologic variables (flow magnitude, frequency, dur...
Autori: Arvydas Povilaitis
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26848

Abstract The ethanol-gasoline blends have brought new challenges to the in-cylinder mixture air-fuel ratio control for the variable fuel characteristics especially in the traditional PFI (Port Fuel Injection) SI (Spark Ignition) engines. This paper studied all the dynamic links in the intake fuel transfer process from the fuel injectors to cylinders, including the wall-wetting effect and injector fuel flow characteristics. A wall-wetting fuel film evaporation model and an injector fuel flow ...
Autori: Dongwei Yao
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26918

There are industrial processes where cold and heat are used. In such a process, a heat pump integrated into a refrigeration system lead to energy savings. This paper analyzes two-stage compression refrigeration combined with a compression heat pump. A case study is made based on a proposed mathematical model and on the measurements performed in an ice cream company. Three operation regimes are simulated for different hot water temperatures obtained from the heat pump. The energetic efficiency, e...
Autori: Aneta Hazi
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27297

Ground water is an important source of clean water supply throughout the world. A growing literature on the management of groundwater which takes into account the interaction of groundwater with surface water resupply sources (e.g., streams or lakes) is driven by concerns of intensified global fresh-water use coupled with increasing industrial and agricultural pollution levels. Our joint laboratory and numerical experiments simulate water withdrawals via two pumping wells from an unconfined aqui...
Autori: Anca Marina Marinov
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27302

In Romania many rivers have been canalized by non-submersible damming, flow diversions and channeling towards new routes, transversal arrangements, etc. The modifications of natural flow regimes brought severe impacts on all ecological functions of wetlands and on the natural functioning of river-floodplain systems. Due to damming only few of the floodplains function nowadays in a natural manner. Rivers and wetlands rehabilitations are bringing the well-known environment benefits, reason for wh...
Autori: Lăcrămioara Vlad
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27462

A 120 kilometers reach of the Prut River, Romania was surveyed and the concentrations of four trace metals (copper, cadmium, lead and zinc) were determined in water and sediments. These elements are the main pollutants expected in the region, as a steel-producing factory in Romania is located in the close neighborhood of an area under protection, the Lower Prut Floodplain Natural Park. Samples were collected in 2010 and 2011 from the water-sediment interface at six locations along the lower sect...
Autori: Marius Lucian Matache
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27612

The Brazilian instruments of environmental policy are mainly geared toward specific uses. They are not usually integrated into an analysis of all land uses. Economic Ecological Zoning is an instrument which can consider multiple land uses. However, in Brazil, this instrument is still not appropriately used to assist with the siting of planning projects. In this context, this paper aims to analyze the ‘usefulness’ of Economic Ecological Zoning for the siting of hydropower plants prior...
Autori: Carolina de Oliveira Jordăo
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27633

The objective of this study was to evaluate the effect of different doses of meat and bone meal (MBM) applied as organic fertilizer on the quality of groundwater in arable fields. The effect of meat and bone meal fertilizer applied at rates of 1.0, 1.5, 2.0 and 2.5 t ha-1 was compared with no fertilization, mineral fertilization, and manure fertilization (10 t ha-1). Groundwater samples for chemical analyses were collected every month during the growing season using piezometers installed in the ...
Autori: Arkadiusz Stępień
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27742

In the framework of the European Commission Blue Growth Strategy, a joint process among European countries has been put in place since 2014 to promote and implement research and innovation actions to increase the number of jobs in the marine and maritime sectors, commonly named ‘blue’, and pursue a sustainable growth in the Mediterranean area. The process has then been extended to the non-European (non-EU) Mediterranean countries. The natural and cultural uniqueness of the Mediterran...
Autori: Margherita Cappelletto
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27786

In this work, we report a methodology to provide emission factors based on micro-reactor studies. We propose emission factors for ammonia (NH3, 158 mg/km), nitrous oxide (N2O, 322 mg/km) and molecular hydrogen (H2, 72 mg/km) for vehicles equipped with three-way catalytic converter (TWC). Our experimental conditions were similar to those prevailing on vehicles during catalyst light-off and transient urban driving cycle. NH3 and H2 emission factors reported in this work are quantitatively simil...
Autori: Gustavo Ariel Fuentes
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27899

Photocatalytic processes are among the most efficient treatment methods of waters polluted with recalcitrant organic substances. Nanotubular TiO2 arrays with photocatalytic properties were obtained in the process of titanium anodic oxidation in the fluoridecontaining electrolyte. Under the proposed conditions of electrolysis, a coherent system of tightly adjoining nanotubes was formed with the internal diameter of 60-80 nm and walls thickness up to 60-65 nm, the tubes height being dependent on p...
Autori: Gheorghe Duca
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28137