Inginerie Mecanică
Biomass gasification has been seen to be especially relevant conversion technologies for dispersed power/energy production, particularly in small and medium capacities. In the present study, it has been developed a model for the gasification process in down draft gasifiers, which can be applied for a corn stover with d…
picture_as_pdfText integral (PDF)The paper presents the wave regime of the Romanian Black Sea coastwise and also the used technology for the wave modeling in laboratory conditions. The wave interaction with the wave energy capturing devices, like the flotation gear type, was also analyzed and is described in this paper. The first part of the article p…
picture_as_pdfText integral (PDF)The present paper refers to an energetically analysis for a small-scale modern substation, which supplies with thermal energy a block with 10 floors and 32 flats, situated in Bucharest. A comparison between energy consumptions for the “constant speed” case and the “variable speed” cases was also made. Three simulation …
picture_as_pdfText integral (PDF)The use of LPG in diesel engine represents an efficient solution to decrease of the pollutants emissions, maintain of the high efficiency that characterize it. Experimental researches were carried on an automotive diesel engine with 1.5 l displacement fuelled with LPG by diesel-gas method at different substitution per…
picture_as_pdfText integral (PDF)In the present the most important aspects of surface water pollution are increasing global primary production of bodies of water due to large amount of nutrients, called eutrophication. The effects induced by the occurrence of this phenomenon on water quality are severe, so that they may become unsuitable for some serv…
picture_as_pdfText integral (PDF)The system SIM-E&H presented in this paper promote an integrated approach of the causal connection between environment and health based on knowledge management principles, and two categories of practical results: a modern information system based on Web server technology, and a set of direct effect tools used to preven…
picture_as_pdfText integral (PDF)According to the European Environmental Agency, soil contamination requiring clean up is present at approximately 250,000 sites in the EEA member countries. And this number is expected to grow. The aim of this experimental investigation was to assess the feasibility of using electrochemical oxidation, an innovative tec…
picture_as_pdfText integral (PDF)The soil moisture retention characteristics are very important functions in water flow through unsaturated media modeling processes.\r\nWe derived here a more general form of soil moisture retention characteristic, using volumetric moisture contents, calculated with the optimized Mualem-van Genuchten parameters. The vo…
picture_as_pdfText integral (PDF)This paper presents an experimental and theoretical study of the oxygen transfer efficiency for a medium bubble aeration system used in hybrid biological wastewater treatment technology for the first attached-growth biological treatment stage. A theoretical model for oxygen transfer was elaborated, the theoretical resu…
picture_as_pdfText integral (PDF)Pumping station scheduling for variable water supply can be optimised by using the Honey Bees Mating Optimization Algorithm (HBMOA). The algorithm HBMOA-M1 applied in this paper is modified with respect to the classical one: the solutions improved during the current iteration, ranked after the queen as fitness, are ins…
picture_as_pdfText integral (PDF)Because of the ecological and environmental restrictions in energy production, the use of small hydropower resources will be economical in the future. Standard pumps could be considered a low cost alternative for hydraulic turbines used in small hydropower plants. The purpose of the paper is to determine the characteri…
picture_as_pdfText integral (PDF)Hydropower plants with reversible units are not only power plants, but also management tools, because they can take on the tasks of peak regulation, frequency modulation, phase modulation, emergency generation in power grid, or inter-basin transfer of water with multiple uses. In this paper, a mathematical model for th…
picture_as_pdfText integral (PDF)The paper presents the methodology used to compute the energy consumption of the “Teiul Doamnei” pumping station in Bucharest. A numerical model of the pumping station and it’s attached water network is created in EPANET, and the pumping station scheduling is implemented via control statements. An analysis over a 24h p…
picture_as_pdfText integral (PDF)The paper offers an insight into the modeling of a variable nozzle turbocharger for automotive control applications. The emphasis is put on modeling the gas flows through the compressor and turbine and the corresponding isentropic efficiencies. The examined models are physically based regression models calibrated using…
picture_as_pdfText integral (PDF)Numerical investigations into an old Francis turbine runner with medium specific speed at off-design conditions are performed. The velocity and pressure fields are computed at off-design conditions using CFD. As a result, the hydrodynamic filed is disturbed inducing vibrations and mechanical problems due to the geometr…
picture_as_pdfText integral (PDF)This paper aims to present a two-dimensional numerical methodology to optimize a symmetrical two-foiled channeling device for vertical axis cross-flow water turbines. The methodology consists firstly on using a simplified steady approach based on a boundary elements method and a boundary layer analysis for a rotor-less…
picture_as_pdfText integral (PDF)This study focuses on water flow in the wake of a hydropower farm equipped with 3 Achard turbine modules. The Achard turbine is a French concept of vertical axis, cross-flow, marine current turbine module, with three vertical delta blades. The comparison between experimental and 2D numerical results has been performed …
picture_as_pdfText integral (PDF)The paper presents a method of power optimization of the wind turbines by changing the pitch angle. There are analysed the structure and the performance of a electro-mechanical servomechanism used to put on position the wind turbine blades so that a maxim out power could be obtained at a given wind speed. Numerical sim…
picture_as_pdfText integral (PDF)The paper presents the impeller-stator interaction into a storage pump with two stages and double entry using numerical investigation. Three-dimensional steady absolute flow is assumed in pump\\\\\\\\\\\\\\\'s fixed parts (like stator) and for the impellers we considered three-dimensional steady relative flow. The nume…
picture_as_pdfText integral (PDF)The paper presents the results of the empirical study, undertaken by the authors, on Romanian project managers, active in IT sector. It approaches the interpersonal communication from the persuasion standpoint and explores the managers\\\\\\\' exercise of influence in attempting to achieve the business objectives. \r\n…
picture_as_pdfText integral (PDF)This paper presents the numerical investigation of coolant flow in pressure tube nuclear reactors using CFD approach. We analyze significant segments of fuel channel with appendages: bundle junctions, spacer planes, bare fuel bundles. The computer code used is an academic version of FLUENT CFD code. The complex flow in…
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