https://sam.ensam.eu:443 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Sun, 14 Jun 2026 09:49:44 GMT 2026-06-14T09:49:44Z http://hdl.handle.net/10985/17996 Experimental and numerical analysis of a novel Darrieus rotor with variable pitch mechanism at low TSR ZOUZOU, B.; DOBREV, Ivan; MASSOUH, Fawaz; DIZENE, Rabah The Darrieus vertical axis wind-turbine (VAWT) has been the subject of numerous recent studies aimed at improving its aerodynamic performance in order to locate it in urban areas. This article is devoted to the study of an original VAWT with variable-pitch and low tip speed ratio TSR which is favorable to noise reduction and can operate at low velocity wind. The aerodynamic performance of this turbine is studied experimentally in wind tunnel as well as by CFD. In order to obtain the 3D-flow field around the wind turbine rotor, the numerical simulations are performed by means of detached eddy simulation method (DES). The simulation of pitch variation is made possible by using sliding-mesh method. Thus a specially created program adapts the pitch depending on the blade azimuthal position during rotation. The obtained results show that adapted pitch blades are preferable because they permit to obtain a power coefficient Cp that rivals other VAWT in the case of . The maximum torque fluctuation during rotation is lower in the case of adapted variable-pitch compared to fixed-pitch and thus the maximum aerodynamic loads on the structure can be reduced. Moreover, the pitch adaptation leads to lower interaction effects between the upstream-blade wake and down-stream blades. Tue, 01 Jan 2019 00:00:00 GMT http://hdl.handle.net/10985/17996 2019-01-01T00:00:00Z ZOUZOU, B. DOBREV, Ivan MASSOUH, Fawaz DIZENE, Rabah The Darrieus vertical axis wind-turbine (VAWT) has been the subject of numerous recent studies aimed at improving its aerodynamic performance in order to locate it in urban areas. This article is devoted to the study of an original VAWT with variable-pitch and low tip speed ratio TSR which is favorable to noise reduction and can operate at low velocity wind. The aerodynamic performance of this turbine is studied experimentally in wind tunnel as well as by CFD. In order to obtain the 3D-flow field around the wind turbine rotor, the numerical simulations are performed by means of detached eddy simulation method (DES). The simulation of pitch variation is made possible by using sliding-mesh method. Thus a specially created program adapts the pitch depending on the blade azimuthal position during rotation. The obtained results show that adapted pitch blades are preferable because they permit to obtain a power coefficient Cp that rivals other VAWT in the case of . The maximum torque fluctuation during rotation is lower in the case of adapted variable-pitch compared to fixed-pitch and thus the maximum aerodynamic loads on the structure can be reduced. Moreover, the pitch adaptation leads to lower interaction effects between the upstream-blade wake and down-stream blades. http://hdl.handle.net/10985/8967 Experimental study of yawed inflow around wind turbine rotor NOURA, Belkheir; DOBREV, Ivan; DIZENE, Rabah; MASSOUH, Fawaz; KHELLADI, Sofiane In this article, we present an experimental study in a wind tunnel of a three-bladed, Rutland 503 model, horizontal axis yawed wind turbine. Power measurement and an exploration downstream wake of the turbine using particle image velocimetry measurements are performed. The variation of power coefficient as a function of rotational velocity is presented for different yaw angles. The results show a loss of power from the wind turbine when the yaw angle increases. The velocity field of the downstream wake of the rotor is presented in an azimuth plane, which passes through the symmetry axis of the rotor. The instantaneous velocity field is measured and recorded to allow for obtaining the averaged velocity field. The results also show variations in the wake downstream due to decelerating flow caused by the yawed turbine rotor. Analysis of this data shows that the active control of yaw angles could be an advantage to preserve the power from the wind turbine and that details near rotor wake are important for wake theories and topredict the performance of wind turbines as well. Sun, 01 Jan 2012 00:00:00 GMT http://hdl.handle.net/10985/8967 2012-01-01T00:00:00Z NOURA, Belkheir DOBREV, Ivan DIZENE, Rabah MASSOUH, Fawaz KHELLADI, Sofiane In this article, we present an experimental study in a wind tunnel of a three-bladed, Rutland 503 model, horizontal axis yawed wind turbine. Power measurement and an exploration downstream wake of the turbine using particle image velocimetry measurements are performed. The variation of power coefficient as a function of rotational velocity is presented for different yaw angles. The results show a loss of power from the wind turbine when the yaw angle increases. The velocity field of the downstream wake of the rotor is presented in an azimuth plane, which passes through the symmetry axis of the rotor. The instantaneous velocity field is measured and recorded to allow for obtaining the averaged velocity field. The results also show variations in the wake downstream due to decelerating flow caused by the yawed turbine rotor. Analysis of this data shows that the active control of yaw angles could be an advantage to preserve the power from the wind turbine and that details near rotor wake are important for wake theories and topredict the performance of wind turbines as well.