The paper presents the achievements of INCDIE ICPE-CA on wind installations provided with counter-rotating turbines. There are envisaged both development an experimental model and results following testing activities, respectively. submits a novelty technological character due to unconventional innovative aspects. It represents foregoing constructive version, preceding turbine prototype rated power 10-15 kW designed for autonomy assurance within specific applications. preliminary...

The paper presents the research results regarding metabolism of microorganisms from domestic wastewater treatment-activated sludge. approached this issue by dielectric spectroscopy measurements, chemical analyses, and specific microbiological techniques. In addition, influence extremely low-frequency (ELF) electric fields (1÷500 Hz) on microbial was studied. Four representative frequencies have been identified: 49.9, 99.9, 130.8, 150.4 Hz using applied to investigated samples. Also, loss...

It is well known that the hydro power plants directly influence habitat and climate.Still, represents a green renewable energy source, not polluting environment if proper measures are applied.The main objective of researches in this field represented by quality water discharged from turbines especially low dissolved oxygen level may have an unfavorable impact over can endanger aquatic life.During summer months, due to thermal stratification dam reservoirs degasification phenomenon resulted...

The results of a pilot-scale study on the influence electric field use for stimulating active sludge in biological purification tank small capacity wastewater treatment plant (up to 600 m3/day) are presented. Through specific comparative chemical tests (DO, COD, N-NH4, and Pt) it was found that, by applying sinusoidal 5 Vrms/m at 49.9 Hz suspension, overall pollutant denitrification process speed is doubled compared with reference case when no stimulation used. Also, under identical...

The use of smart technologies and the Internet Things (IoT) is becoming more popular in order to enhance overall building performance by monitoring parameters related occupants’ comfort health built environment. A new modular, custom-made replicable IoT system proposed based on an Arduino development board (MKR WiFi 1010) connected Cloud. An Application Programming Interface (API) enables integration this with other possible ones, thus making replicable. series were simultaneously monitored...

The research presented in this paper involves the design of a power control system for hydrokinetic turbine previously tested real operating conditions. A maximum point tracking (MPPT) algorithm was designed and simulated using required parameters specific electric generator. proposed consists generator connected to turbine, three-phase uncontrolled rectifier, direct current (DC) boost converter with MPPT extract available power, buck amount delivered load. In order test algorithm, we built...

This paper describes the experimental study of a behavioural barrier consisting bubble curtain placed near an ecological river water intake, aiming to assess curtain’s influence on velocity field flowing in intake proximity. The scientific novelty is given by solution operating tandem with dedicated generator used for avoiding fish entrapment. present research based run-of-river without dam riverbed, maintaining mountain rivers longitudinal connectivity. An setup was designed and built...

In this paper, a system to stimulate in extremely low frequency (ELF) electric field the microbiological activity of microbial flora active sludge wastewater treatment plant is presented. The designed and realized was tested industrial environment with without ELF stimulation. By comparing two cases for same degree pollutants elimination from wastewater, it resulted that application significantly reduces processing times biological stages (to approximately half). Thus, energy consumption...

The paper presents theoretical considerations on gas bubbles behavior -analytic calculation of bubble time formation, extra pressure needed for the formation and detachment, size correlation between liquid superficial tension.In order to evaluate relation calculation, results tests performed different metallic perforated plates Ø 60, with a specific number orifices diameters, were used.The varies from approximately 171 Pa MPP 0.9 mm 245 0.2 orifices.

The hydro renewable energy provides a reliable power source; it does not pollute the air or land but affects aquatic habitat due to low dissolved oxygen (DO) level in water discharged from turbines. Hydro-turbines intake generally withdraws bottom layer of reservoirs with DO level. In different methods used for improving downstream hydropower plants volume is considered be main parameter injection. energetic consumption affected, terms loss turbine efficiency authors propose study show...

The aim of this paper is the theoretic and experimental study hydrodynamics mass transfer swarm bubbles generated by fine bubble diffusers (FBD) made from ceramics.Thus hydrodynamic parameters dispersed air-water system (pressure loss on FBD, size distribution, global gas hold up) were experimentally determined.Regarding transfer, volumetric coefficient Kl a , standard oxygen rate (SOTR) aeration efficiency (SAE) also determined.The results showed that increases with air flow there an...

The paper presents the achievements of INCDIE ICPE-CA in field permanent magnets electric generators, having both rotating armatures, developed for wind energy conversion with systems counter turbines. innovative design these generators has aimed to obtain an increased speed and eliminate multiplier, which introduces additional losses. Experimental results obtained by testing two confirm obtaining parameters proposed frame theme.

The objective of the paper is to study influence certain shroud types suitable for horizontal axis hydrokinetic turbines using experimental testing in order increase energy conversion efficiency. scale model shrouded turbine tested on a dedicated bench axial hydraulic models. Two shrouds were be compared: convergent and divergent shroud. rotor made 3D printer technology at water velocity 0.9 m/s closed-circuit bench. facility allows determination power extracted each five distinct positions....

The behaviour of some insulating fluids in contact with copper foil and / or insulation paper under thermal stress (110�30C for 1000 hours), a closed system (the access atmospheric oxygen being limited), has been studied by determining the changes viscosity concentration CO2 CO. experimental data revealed that, following applied heat treatment, change esters-based (both synthetic vegetable) is approximately 7 times lower than case investigated mineral oils. It also found ageing, gas content...

Abstract Side weirs are hydraulic structures used to divert the excess flow from a main channel into lateral one at diversion or intakes, in order control water surface elevation reroute part of discharge. Flow over side weir is considered be typical case spatially varied flow, with decreasing discharge along and varying crest. The objective paper apply various numerical modelling approximations (1D, 2D 3D) using HEC-RAS ANSYS Fluent software virtually reproduce characteristics canal Valea...

The human activities, especially the energy production from fossil fuels and transport sector, produce huge amounts of CO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> , which is a greenhouse gas [1]. In this context, developing expanding phototrophic microalgae suitable way to reduce effect by converting anthropogenic into organic mass oxygen. It should be also mentioned that mass, including algae, high added value product.

The objective of the paper is to identify a power prediction method suitable horizontal axis hydrokinetic turbines using simulation, laboratory testing and operational data collected from literature. An open source framework for simulation design used in order determine optimal blade geometry small rotor models which are then tested dedicated experimental bench axial hydraulic turbine models. results as well related projects or scientific articles predict extracted given water velocity range...

The amounts of flammable gases formed in some transformer oils during the long-term storage (1000 hours) at 110 � 3�C closed containers (limited access to atmospheric oxygen) were determined qualitatively and quantitatively by gas chromatography technique. comparative experimental results showed that when two types mineral oils, one synthetic oil vegetable are simultaneously contact with copper insulating paper, total amount thermal aging is about 40 times higher than ester based oils. It...

Abstract With the significant advance in exploiting wind energy, there has been a shift research from study of conventional systems to counter-rotating due additional energy input second rotor. The paper presents results on achieving an increase efficiency power conversion systems. For this purpose, have designed different sizes rotors, were 3D printed and tested open-circuit aerodynamic tunnel for velocities axial distances between rotors. constructive design consisting smaller diameter...

This paper presents an exhaustive study regarding the behaviour of copper in various insulating fluids when exposed to 1100C for 1000 hours closed systems, with no access atmospheric oxygen. Following analysis carried out, it was found that variation oxygen concentration investigated oil samples, during thermal treatment, may be best described using exponential decrease versus time. Moreover, from gas chromatography determinations respect evolution CO and CO2 content oils treatment one out...

The corrosion state of an underground metallic pipeline �161 mm and 565 m length was assessed by specific electrical electrochemical measurements. investigated pipe, buried in 1997, protected against successive layers bituminous material with a total thickness 1 to 1.2 mm. crosses three electrified railway lines (50 Hz - 28 kV), then its route is approximately parallel these lines; thus, the induced AC voltages between line ground were calculated obtaining values 4.05 7.1 Vrms, good...

The paper presents the analytical solution used to calculate depression which appears under different types of impellers. This can be useful as a preliminary calculus estimate magnitude created at rotational speeds, in order not damage equipment from systems, such hydraulic turbines. authors obtain variable radius zone, pressure inside zone and height. theoretical approach, itself numerical results presented article are original. In validate proposed calculus, experiments were carried out...

The corrosiveness and thermal stability of five types insulating oils - both in contact contactless with copper S235J2G3 carbon steel have been studied through gravimetric determination, XRF analysis dynamic viscosity measurements. experimental results showed that, after a heat treatment (700 hours) at 110± 30°C, the weight investigated samples by mineral oil drops (by volatilization) to be between 7 7.5%. For vegetable not registered remarkable changes weight. analyzes revealed that new...