Search results for "EROD"

Forces and flow structures evolution on a car body in a sudden crosswind

2014

A vehicle driver is commonly exposed to strong side air flows, for example when passing through a wind gust. The aerodynamic efforts generated in these situations may induce undesired lateral deviations, which can lead to dramatic effects, if the driver is surprised. In order to simulate a sudden yaw angle change on a moving vehicle, a double wind tunnel facility, adapted from the one of Ryan, Dominy, 2000. Wake Surveys Behind a Passenger Car Subjected to a Transient Cross-wind Gust. SAE Technical Paper No. 2000-01-0874 is developed. Two Windsor car body models, differing from their rear geometry, are analysed. The transient evolution of the side force and yaw moment aerodynamic coefficient…

Wind turbine modeling using the bond graph

2011

Author's version of a chapter in the book: Proceedings of the IEEE International Symposium on Computer-Aided Control System Design. Also available from the publisher at: http://dx.doi.org/10.1109/CACSD.2011.6044572 This paper addresses the problem of bond graph methodology as a graphical approach for modeling wind turbine systems. In this case, we consider the modeling of a wind turbine system with individual pitch control scheme and the interaction with tower motions. Two different bond graph models are presented, one complex and one simplified. Furthermore, the purpose of this paper is not to validate a specific wind turbine model, but rather show the difference between modeling with a cl…

Local DoS applications with micro wind generation systems

2015

In this paper a wind electrical power generation system for Distributed on Site (DoS) applications is proposed. This system was developed and conceived in order to guarantee simple installation, use and service, obtaining a product that can be easily industrialized and put into the market with limited costs. The field of application of such an electrical generation system is addressed towards domestic or at the most toward condominium applications concerning moreover the opportunity of working in addition to combined photovoltaic and solar-thermal systems to enhance the renewable energy generation at house level (DoS). The proposed system has its hot spot in the blades shape, in the wind fl…

On the induced drag reduction due to propeller-wing interaction

1995

AbstractThe aerodynamic interaction between a wing and a couple of propellers in tractor configuration is investigated by means of a model based on the lifting line concept and under the assumption of quasi-steady incompressible motion of inviscid fluid. The ways the propellers influence the wing performances, particularly the induced drag, are analysed. It turns out that the lift increase and the possible drag reduction depend strongly on the direction of the blade rotation and on the propeller distances from midspan, and result from two main effects: the direct propeller induction on the wing and the modification of the lift distribution along the span. An additional nonlinear (mixed) con…

Effects of electrical and mechanical parameters on the transient voltage stability of a fixed speed wind turbine

2011

Abstract In this paper the dynamic behaviour of a wind turbine connected to the grid is examined. The model of the fixed speed wind turbine has been developed with the Simulink simulation tool (Matlab Inc.) It is composed of the induction generator, the shaft system, an aerodynamic model of the wind turbine rotor and the pitch control system. Using this model, a three-phase fault is applied close to the wind turbine and cleared by disconnecting the faulty line. The rigorous implementation of the simulink model allowed the authors to evaluate the exact dependence of various electrical parameters for the induction generator on voltage stability. Furthermore, the effects of wind turbine mechan…

Optimization of a Vehicle Shape by CFD Code

2005

In this paper, fluid dynamics simulations have been executed using a CFD (Computational Fluid Dynamics) commercial code, on a Maserati Biturbo mod. 222 - 1988. At first some surfaces are optimised, choosing the more important ones for the reduction of the resistance, by a manual variation of their geometry, hence a large surface is optimised in an automatic way, by means of an own software, developed in the MatLab environment, returning the optimised surface according to a specific objective function (the resistance in this paper). The aerodynamics resistance results are given under the form of aerodynamics penetration coefficient CD, taking into account the vehicle shape effect, the speed,…

Effects of Electrical Parameters of Induction Generator on the Transient Voltage Stability of a Fixed Speed Wind Turbine

2008

This paper describes the effect of electrical parameters of the induction generator on the transient voltage stability of a fixed speed wind turbine connected to a simple grid; the dynamic behavior of a wind turbine connected to the grid is examined. The model of the fixed speed wind turbine has been developed in the simulation tool Matlab/Simulink. Itpsilas composed by the induction generator, the shaft system, the aerodynamic model of the wind turbine rotor and the pitch control system. Using this model, a three-phases fault is applied close to the wind turbine and cleared by disconnecting the faulted line. The effect of different electrical parameters of the induction generator on the vo…

Regional analysis of soil erodibility in Sicily

2007

MISURA DELL’ERODIBILITA’ DEL SUOLO NELLE PARCELLE SPERIMENTALI DI SPARACIA, IN SICILIA

2010

Nell’indagine è stata effettuata una determinazione sperimentale del fattore di erodibilità del suolo, K, della USLE basata sulle misure effettuate nel suolo argilloso di Sparacia. Il valore medio annuo del suddetto fattore, misurato su parcelle di lunghezza, , comprese tra 11 e 44 m, è risultato decrescente con . La stima indiretta del fattore di erodibilità è risultata del 46% inferiore rispetto alla misura effettuata nella parcella di riferimento, lunga cioè 22 m, e si è attestata su un valore intermedio tra le misure di K ottenute nelle parcelle di 33 e 44 m. Un simile effetto di scala è stato riconosciuto anche con riferimento ai valori annui e a quelli stagionali del fattore di erod…

Effect of ultrasound technology combined with binary mixtures of ethanol and water on antibacterial and antiviral activities of Erodium glaucophyllum…

2019

Abstract Erodium glaucophyllum is a common Mediterranean herb known for its health benefits. In this study, Erodium extracts obtained from different extraction methods (conventional vs ultrasound-assisted extraction) and extraction solvents (aqueous and hydroethanolic) were evaluated in microbiological media to determine their effects on bacteria (Salmonella enterica, Staphylococcus aureus, Listeria innocua, Bifidobacterium lactis and Lactobacillus casei) and antiviral activity (hepatitis A virus and murine norovirus). Both, the extraction method and solvent were found to be important contributing factors. Ultrasound-assisted extraction yielded the highest level of desirable Erodium-extract…