NUMERICAL MODELING OF UNSTABLE FLOWS IN CONDUCTS WITH VARIABLE GEOMETRY
Article dans une revue avec comité de lecture
JournalScientific Bulletin - "Politehnica" University of Bucharest. Series D, Mechanical engineering
Changes in the system flow of a fluid in a conduct often cause sudden changes in pressure and give rise to so-called unstable flows. So, the study of the phenomenon of unstable flows aims to determine ifthe pressure in a system is within the prescribed limits, following a perturbation of the flow. In the objective of studying the rangeof a water hammer, an examination of variations in velocity or flow and pressure resulting from inappropriate operation of the hydraulic system is made. This study presents a numerical modeling of the phenomenon of instable flows in load conducts with variable geometries. The characteristic method is used to solve the governing equations. Thanks to the AFT Impulse industrial program, very interesting and very practical numerical resultsare obtainedto describe the phenomenon of instable flows inconducts with variable geometry. And to more illustrate the graphical presentation two cases are graphically overlay for each of the two types of models (slow closing and rapid closingof the valve).
Files in this item
Showing items related by title, author, creator and subject.
Article dans une revue avec comité de lectureCOGNET, Vincent; COURRECH DU PONT, Sylvain; DOBREV, Ivan; MASSOUH, Fawaz; THIRIA, Benjamin (Royal Society, The, 2017)Wind energy is becoming a significant alternative solution for future energy production. Modern turbines now benefit from engineering expertise, and a large variety of different models exists, depending on the context and ...
Article dans une revue avec comité de lectureNOURA, Belhadj; DOBREV, Ivan; KERFAH, R.; MASSOUH, Fawaz; KHELLADI, Sofiane (2016)The wake and the lack of existing velocity behind the wind turbine affect the energy production and the mechanical integrity of wind turbines downstream in the wind farms. This paper presents an investigation of the unsteady ...
Communication avec acteDOBREV, Ivan; MASSOUH, Fawaz (BULTRANS -2014 Proceedings, 2014)The paper presents a study of aerodynamic characteristics of a car, which has the simplified geometric shape, so called Ahmed body. Flow around the body and the influence of its rear slant angle on drag are widely studied ...
Communication avec acteVELKOVA, Cvetelina; DOBREV, Ivan; TODOROV, Michael; MASSOUH, Fawaz (BulTrans-2012, 2012)The aim of the computational study is to present different approach for numerical modeling of airfoil dynamic stall as the airfoil is pitched at a constant rate from zero incidences to a high angle of attack. An application ...
COMPUTATIONALLY INEXPENSIVE FREE VORTEX METHOD TO OBTAIN VORTEX CORE POSITION IN THE WAKE OF A HORIZONTAL AXIS WIND TURBINE Article dans une revue avec comité de lectureMEGHLAOUI, Issam; DOBREV, Ivan; MASSOUH, Fawaz; BENRETEM, A. Ouahab; KHALFA, Dalila (Begell House, 2017)This work aims to develop a free wake model, allowing quick simulation of flow through a horizontal axis wind turbine. The rapidity of computation is particularly interesting when this aerodynamic model is integrated with ...