Journal of Physics: Conference Series PAPER • THE FOLLOWING ARTICLE ISOPEN ACCESS Effects of freestream turbulence on the wake growth rate of a model wind turbine and a porous disc

2022-06-05
Öztürk, Buğrahan
Hassanein, Abdelrahman
Akpolat, Tuğrul
Abdulrahim, Anas
Perçin, Mustafa
Uzol, Oğuz
This study presents the results of an experimental investigation that focuses on quantifying the differences between the spreading rates of a model wind turbine wake and a porous disc wake at different freestream turbulence intensity levels. Two-dimensional two-component particle image velocimetry (2D2C PIV) measurements are performed within the wakes of a model wind turbine and a porous disc (up to 7D downstream) of the same diameter and a matching thrust coefficient. The wind turbine is operated at a Tip Speed Ratio (TSR) of 2 in order to have matching thrust coefficient conditions for a consistent wake comparison. The results show that the mean wake flow field (both near and far wake) is significantly different for the wind turbine compared to the porous disc even if they are operating at similar, high or low, freestream turbulence levels. The wake of the wind turbine recovers much faster than that of a porous disc with a matching thrust coefficient especially in the far wake region at both low and high freestream turbulence levels. On the other hand, the data shows that the far wake of the turbine operating at low freestream turbulence is very similar to that of the disc operating at high freestream turbulence. This suggests caution and stresses the importance in choosing the freestream turbulence intensity level when using porous discs to represent wind turbines in wind tunnel studies.
The Science of Making Torque from Wind (TORQUE 2022)

Suggestions

AMBIENT TURBULENCE INTENSITY EFFECTS ON THE CHARACTERISTICS OF WAKE DEVELOPMENT OF A MODEL WIND TURBINE AND A MATCHED POROUS DISC
Öztürk, Buğrahan; Uzol, Oğuz; Department of Aerospace Engineering (2022-9-1)
This thesis study aims to observe the ambient turbulence intensity effects on the wake development of a model wind turbine and a matched porous disc. Comprehensive wind tunnel experiments are conducted in the wake of the model wind turbine and the porous disc up to 7 diameters downstream through two-dimensional two-component particle velocimetry. The wakes of the model wind turbine and the porous disc are investigated in terms of the mean flow field, turbulence, wake decay, and wake spreading characteristic...
Experimental investigation of the effects of tip injection on the characteristics of the tip vortex on a model wind turbine
Anık, Ezgi; Uzol, Oğuz; Department of Aerospace Engineering (2015)
This study presents the results of an experimental study performed on a horizontal axis wind turbine to investigate the effects of spanwise steady tip injection on the tip flow characteristics of a model turbine. Experiments are performed in front of an open-jet wind tunnel facility on a specially designed model wind turbine that has a 3-bladed rotor with NREL S826 airfoil profile. The turbine has a specially designed injection system which consists of a pressure chamber, a hollow shaft, pressurized hub and...
Experimental Study on the Effects of Winglets on the Performance of Two Interacting Horizontal Axis Model Wind Turbines
Ostovan, Y.; Uzol, Oğuz (2016-10-07)
The focus of this experimental study is to investigate the effects of winglets on the performance of two interacting similar horizontal axis model wind turbines. For this purpose, a downwind winglet is designed and manufactured to be attached to the blade tips of the upstream turbine. A set of wing extensions with the same length as the winglets is also produced to be compared to the winglets. Power and thrust coefficients of both turbines are measured with winglets as well as with wing extensions attached ...
Experimental investigation of surface roughness effects on the flow boiling of R134a in microchannels
Jafari, Rahim; Okutucu Özyurt, Hanife Tuba; Ünver, Hakkı Özgür; Bayer, Özgür (2016-12-01)
This study experimentally investigates the effect of surface roughness on the hydrodynamic and thermal performance of microchannel evaporators. Three micro-evaporators of the same dimensions and different surface roughness have been fabricated by micro-WEDM. Each micro-evaporator consists of forty rectangular microchannels of 700 mu m height, 250 mu m width, and 19 mm length. A microscale vapor compression refrigeration cycle has been constructed to carry out the experiments. R134a is used as the refrigeran...
Comparative study of transient and quasi-steady aeroelastic analysis of composite wind turbine blade in steady wind conditions
Sargın, Hakan; Kayran, Altan; Department of Aerospace Engineering (2014)
The objective of this study is to conduct a comparative study of the transient and quasi-steady aeroelastic analysis of a composite wind turbine blade in steady wind conditions. Transient analysis of the wind turbine blade is performed by the multi-body dynamic code Samcef Wind Turbine which uses blade element momentum theory for aerodynamic load calculation. For this purpose, a multi-body wind turbine model is generated with rigid components except for the turbine blades. For the purposes of the study, a r...
Citation Formats
B. Öztürk, A. Hassanein, T. Akpolat, A. Abdulrahim, M. Perçin, and O. Uzol, “Journal of Physics: Conference Series PAPER • THE FOLLOWING ARTICLE ISOPEN ACCESS Effects of freestream turbulence on the wake growth rate of a model wind turbine and a porous disc,” presented at the The Science of Making Torque from Wind (TORQUE 2022), Zuid-Holland, Hollanda, 2022, Accessed: 00, 2022. [Online]. Available: https://hdl.handle.net/11511/97948.