On the wake pressure footprint and its potential application for wake flow analysis
2013 (English)In: European Wind Energy Conference and Exhibition, EWEC 2013, 2013, 939-945 p.Conference paper (Refereed)
This paper introduces a new wake analysis technique behind wind turbines, called pressure footprint (p-f) method, as a simple technique for wind tunnel experiments as well as for field measurements. It is based on the assumption that the pressure at ground is related to the total pressure at the hub height, which in turn can be correlated to the velocity deficit of the wake. The p-f method requires that the static pressure can be measured on the ground and for this purpose we here use a pressure plate with 400 pressure taps. A single wind turbine model was positioned in the middle of the plate and the pressures were measured using a scani-valve. The static and total pressures at hub height were also measured. The effect on the wake pressure footprint when varying the hub height was studied, and by an appropriate definition of the applied pressure coefficient the variation of the footprint size vanishes, which is an important first step in relating the footprint area to the velocity deficit in the wake. We also show the interaction of two wind turbine models, located on the same centre line, with varying reciprocal streamwise distance. With the current method the relative size between the upstream and the downstream pressure footprint remains constant with a factor of two. Next, we will investigate the correlation between the pressure footprint and the velocity deficit in the wake by performing particle image velocimetry measurements in the same setup.
Place, publisher, year, edition, pages
2013. 939-945 p.
Wind power, Wind turbines, Applied pressure, Downstream pressure, Field measurement, Particle image velocimetry measurement, Static pressure, Velocity deficits, Wind tunnel experiment, Wind turbine modeling, Wakes
IdentifiersURN: urn:nbn:se:hig:diva-19485ScopusID: 2-s2.0-84903432947ISBN: 9781632663146OAI: oai:DiVA.org:hig-19485DiVA: diva2:817915
European Wind Energy Conference and Exhibition, EWEC 2013, 4-7 February 2013, Vienna