PhD student in CASED

PhD student for Concurrent Aero-Servo-Elastic analysis and Design of wind turbines
Apply before: 01.12.2008 at 12:00 (noon)
The CASED project with the full title “Concurrent Aero-Servo-Elastic analysis and Design of wind turbines” is a four year project supported by the Danish Council for Strategic Research, wherein Aalborg University and the Technical University of Denmark are collaborating with Vestas Wind Systems A/S on improving the cost-effectiveness and reliability of wind turbines through new knowledge and systematic methods for analyzing and designing the interaction of structural dynamics, aerodynamics, and controllers of a complex aero-servo-elastic system such as a wind turbine. 

To achieve these goals Risø DTU seeks one of three PhD students who will work together on aero-servo-elasticity of wind turbines from different angles with help from individual supervisors: Jakob Stoustrup (Automation & Control, AAU), Morten Hartvig Hansen (Risø National Laboratory for Sustainable Energy, DTU), and Niels Kjølstad Poulsen (Informatics & Mathematical Modeling, DTU).

There are three good reasons to join the CASED project as a PhD student: You will work with the young interdisciplinary science of aero-servo-elasticity, you will cooperate with the world-leading wind turbine manufacturers on real-life prob-lems, and you will have the chance to build up a novel community within aero-servo-elasticity of wind turbines.


Wind turbines have not always been looked upon as a complex aero-servo-elastic system. In early designs of stall-regulated turbines, there was no need for an active controller due to the passive power regulation by flow separation, and even the structural analysis was limited to statics for ensuring that the turbine could withstand the aerodynamic loads. As turbines became larger and more flexible, increased levels of vibrations and instabilities due to the aeroelastic interaction of turbine flexibility and aerodynamic forces led to the inclusion of aeroelastic simulations and eigenvalue analysis in the design process. Modern pitch-regulated and active stall-regulated turbines are today considered to be complex aero-servo-elastic systems, and their designs involve numerous advanced aero-servo-elastic simulations. Controllers play in-creasing roles in the continuous optimization of performance over cost through reduction of loads using the generator torque and blade pitch as actuators, or innovative aerodynamic devices like trailing-edge flaps (see picture). In CASED, you will contribute new knowledge of the aero-servo-elastic behaviour of wind turbines that can enhance the use of control-lers, e.g. by trailing-edge flaps. 


Aero-servo-elastic simulation tools such as the multi-body code HAWC2 are used for estimations of power performance and structural loads in the design of modern wind turbines. However, there are no tools or methods for systematic analysis and design of the aero-servo-elastic behaviour with all three parameter spaces opened for concurrent optimization, where the aeroelastic (structural and aerodynamic) and controller designs are done in an integrated process. In CASED, you will help to develop new tools and methods for concurrent ASE design with systematic search towards a common optimum.


Traditionally, the mechanical and control engineers use different terminologies. A long-term objective of CASED is to de-velop an ASE-community between the two engineering branches within wind energy, similar to the aeroelastic community between engineers of fluid and solid mechanics that has developed in the last 30 years within aeronautics and wind en-ergy. As a PhD from the CASED project, you will have the chance to become a key member of such novel community.


The applicant should have a M.Sc. or similar. It is expected that the applicant will have a background in engineering with focus on fluid dynamics and structural dynamics, knowledge about control and experience of programming.

Terms of employment

Terms of employment will be in accordance with those of the scientific staff of universities. The place of work will be Risø DTU in Roskilde. 


We must have your online application by 1 December 2008. Please open the link “apply online” and fill in the application form and attach your application and CV. 

Further information 

If you need further information concerning this position or the Division of Wind Energy,  please call  senior scientist Morten Hartvig Hansen at +45 46 77 5971. You can also read more about the Wind Energy Division and Risø DTU