TU Delft performs R&D icing and low temperatures tests on new de-icing technique at OWI-Lab’s climate chamber

As the deployment of wind energy in cold climate regions is growing, engineers are looking into optimisation projects that deal with cold climate compliance and potential icing issues that can occur on the rotor blades in cold climates. Due to good wind conditions at most cold climate sites, an increased air density, low population densities at such locations, and new technological solutions that deal with the challenges associated to low temperatures and icing, the cold climate wind power market is gaining momentum.

IEA Wind: Task 19 - Wind Power in cold climates, an international expert working group within IEA R&D Wind, that deals with wind energy in cold climates since 2002, reported at the Winterwind conference in 2014 the potential of this relatively new market for wind power. Apart from the market study that indicated a 60GW installed base of wind power in cold climate back then in 2012, also 50GW was projected for the near future between 2013 and 2017 which is currently in progress. The report also indicated an increase in the awareness for cold climate challenges and an increasing demand for dedicated cold climate technologies with regard to anti- and de-icing solutions for rotor blades (see publication here).

In 2012, OWI-Lab installed a big climatic test chamber tailored on the demands of the wind power business to deal with validation and verification testing in extreme climatic environments. The test facility enables companies and universities to deal with experiments and validation test projects in either cold climate, hot climate, tropical climate and offshore environment. Since it’s opening the facility has supported several OEM’s and component suppliers with climate chamber testing of gearboxes, converters, transformers, service cages and other technologies associated to wind turbines.

Cold climate testing, mainly cold start-up performance testing and low temperature design verification testing of large and heavy components has been the speciality of the lab.

Due to the large dimensions(10,6m x 7m x 8m), large cooling power and fast deep cooling possibilities to -60°C the climate chamber is also useful to perform icing tests. Either anti-icing as de-icing prototypes can be validated by using ice spray guns in the climate chamber in order to perform experiments in a controlled environment. With regard to this topic, OWI-Lab supported TU Delft in the development of a new electro-thermal de-icing system based on nanosecond pulsed DBD plasma actuation that has potential for rotor’s blade/wing anti-/de-icing. Certain R&D tests were performed in the climate chamber last year in order to support the ongoing development of a prototype.  

DBD plasma actuators have been widely investigated in aerodynamic research during the past years for their unique features and their flow control properties. Nanosecond pulsed DBD plasma actuators, were found to drive an ultrafast gas heating mechanism. In literature temperature increases of the gas right above the actuator of several 100K are reported.[1] In order to find a useful application for this heating mechanism, experiments were performed at the OWI- Lab’s climate chamber to test the possibility of melting ice formed directly on DBD plasma actuators.


.      [1] D. L. Rusterholtz, D. A. Lacoste, G. D. Stancu, D. Z. Pai, and C. O. Laux, Ultrafast heating and oxygen dissociation in atmospheric pressure air by nanosecond repetitively pulsed discharges, Journal of Physics D: Applied Physics 46 (2013).

This conducted research could be interesting for the development of future de-icing applications using plasma actuators on aerodynamic surfaces such as wind turbine rotor blades. Different plasma actuator configurations were tested in the climate chamber at a temperature of -20 degrees C while using an ice-spray gun to form layers of glaze and rime ice on the plasma actuators. The energy consumed by the plasma actuator during the de-icing process was monitored as well as the heating of the surface using a thermal camera. The experiments showed that the actuator is able to melt several millimetres of ice layer within few hundreds of milliseconds. This speed, in combination with low energy consumption, could pose a great advantage on this technique with respect to currently existing de-icing techniques.

“We did a 3-day testing campaign at OWI-Lab as this type of controlled testing environment is not available at TU Delft university. The conducted tests gave us insights on what aspects to focus while further developing a de-icing technique based on ns-DBD plasma actuators.”

TU Delft will present their research and insights on this new developed de-icing technique at the Winterwind conference in Åre (Sweden) taking place in February 2016.

About OWI-Lab

OWI-Lab is the Belgian Research, Development and Innovation (RD&I) platform for wind energy. At the test facility in Antwerp OWI-Lab deals with the environmental testing of cold climate, icing climate, hot climate, offshore and tropical climate wind turbine solutions in their large climatic test chamber.

The test facility is well equipped to cope with cold climate and icing compliance testing of CC-machinery, anti-icing technology and de-icing solutions. OWI-Lab is the Belgian representative in the IEA Wind Task 19 expert group on cold climate wind power and supports the research and development of reliable solutions for the cold climate wind power market.

Contact: pieterjan.jordaens@owi-lab.be

More information about our climatic test service:http://www.owi-lab.be/content/climate-chamber-testing

About TU Delft 

These experiments were performed by the aerodynamic department of the faculty of Aerospace Engineering of Delft University of Technology. The aerodynamic group has been investigating plasma actuators for several years as promising flow control devices.  

The faculty of Aerospace engineering of Delft university of Technology is the largest aerospace engineering faculty in Europe with almost 2400 students. Its international character is underlined by the fact that 34% of their students are international students. Delft university of technology is one of the world’s leading technology universities ranked 19th in the world on Engineering & Technology by Times Higher Education (2016).

Contact:

(w.r.t. this experiment): jakobvdb@gmail.com

correale.giuseppe@gmail.com

TU Delft: info@tudelft.nl