Final Report Summary - UNAELCO (Unsteady aeroelastic control for multi-MW wind turbine rotors)
The overall objective of the project is to enhance the knowledge and develop advanced methods and tools for the research and development of unsteady aeroelastic control concepts for multi-MW wind turbine rotors. The focus is on the development of deeper understanding of the unsteady aerodynamics phenomena in combination with the operation of the distributed load control devices in wind turbines and on the evaluation of the benefits of using advanced models and controllers in the predictions of aeroelastic simulations. From the present stage of proven concepts, and first order numerical and experimental predictions, the project will contribute to the development of the research field to a new stage where it constitutes a complete, reliable and robust approach to system design, which is ready for prototype testing, with the target towards lowering the cost of energy produced by modern large-scale wind turbines. This will further strengthen the knowledge transfer and integration in the research field and enhance the collaboration between relevant research institutes.
The project focuses on the development of deeper understanding of the unsteady aerodynamics phenomena in combination with the operation of the distributed load control devices in wind turbines and on the evaluation of the benefits of using advanced models and controllers in the predictions of aeroelastic simulations. More specifically, the main objectives of the project in the first reporting period are to investigate and develop higher fidelity unsteady aerodynamic models for wind turbines with distributed control features and to perform wind tunnel experiments for verification and demonstration purposes. Additional supporting project objectives are considered the dissemination and transfer of knowledge and the training of the main researcher. In order to achieve accurate predictions of the aeroelastic response and the load reduction, development and verification of improved unsteady aerodynamic models are pursued. The research activities consist mainly of numerical investigations focusing on improved predictions of the aeroelastic response of wind turbines equipped with distributed control devices and overall system design optimization. Firstly, the development of higher fidelity aerodynamic models to be included in wind turbine aeroelastic design tools is carried out. The refinement of existing aerodynamic models concerning the effects of the distributed control devices is considered necessary. Wind tunnel experiments at a blade section level are performed for verification purposes of unsteady aerodynamic models. The main results of the research activities consist primarily of the evaluation of the benefits in accuracy and reliability with the advances in the aerodynamic models. The advances in the numerical simulations and the evaluation of the results will finally provide guidelines for the system design in terms of specific component characteristics.
The details of the activities are summarized below:
• Task 1.1: Refinement and evaluation of 2D unsteady aerodynamics models for airfoils with control devices
• Task 1.2: Development of advanced wake model
• Task 1.3: Coupling of 2D unsteady airfoil model with wake model and simulations of verification test cases
• Task 1.4: Development of engineering model for unsteady aerodynamics of rotors with distributed load control devices
• Task 5.1: Wind tunnel tests at various steady and dynamic angle of attack and flap motion cases
• Task 5.2: Wind tunnel tests at various extreme (gust) wind input cases
• Task 6.1: Integration of results into design recommendations for involved technology and tools
• Task 6.2: Various outreach activities
• Task 7.1: Advanced training in unsteady aerodynamics
• Task 7.2: Development of project management and proposal writing skills
Task 1.1 has provided a verified model to be utilized in Task 1.2. Activities in task 1.2 have contributed to the development and verification of the unsteady wake model with two active device concepts implementations for the case of a wing and for the case of a three-blade rotor. The model is used in an analysis in Task 1.3 with the target of achieving Milestone 1.1 'Investigation of improved predictions using higher fidelity coupled unsteady aerodynamics model'. The resulting activities with the continued Task 1.4 has been compiled in Deliverable 1.1 ' Report on the investigations using a higher fidelity coupled model and the derived engineering models for the unsteady aerodynamics of wind turbines rotor with distributed load control features'. Tasks 5.1 and 5.2 with the target of achieving Milestone 5.1 ‘Wind tunnel results for a blade section with a load control device at various motion and inflow conditions’ are completed. The results have been disseminated in Deliverable 5.1 ‘Report on wind tunnel results of the blade section with the control device’.
The expected results of the research activities consist primarily of the (1) evaluation of the benefits in accuracy and reliability with the advances in the aerodynamic models. The benefits will be demonstrated through the (2) results acquired from the improved full aeroelastic calculations in various operating conditions. Moreover, it is expected that (3) the implementation of integrated control approaches and inflow sensing will further improve the system performance in terms of both load reduction and power enhancement. The advances in the numerical simulations and the evaluation of the results will finally provide (4) guidelines for the system design in terms of specific component characteristics.
The project focuses on the development of deeper understanding of the unsteady aerodynamics phenomena in combination with the operation of the distributed load control devices in wind turbines and on the evaluation of the benefits of using advanced models and controllers in the predictions of aeroelastic simulations. More specifically, the main objectives of the project in the first reporting period are to investigate and develop higher fidelity unsteady aerodynamic models for wind turbines with distributed control features and to perform wind tunnel experiments for verification and demonstration purposes. Additional supporting project objectives are considered the dissemination and transfer of knowledge and the training of the main researcher. In order to achieve accurate predictions of the aeroelastic response and the load reduction, development and verification of improved unsteady aerodynamic models are pursued. The research activities consist mainly of numerical investigations focusing on improved predictions of the aeroelastic response of wind turbines equipped with distributed control devices and overall system design optimization. Firstly, the development of higher fidelity aerodynamic models to be included in wind turbine aeroelastic design tools is carried out. The refinement of existing aerodynamic models concerning the effects of the distributed control devices is considered necessary. Wind tunnel experiments at a blade section level are performed for verification purposes of unsteady aerodynamic models. The main results of the research activities consist primarily of the evaluation of the benefits in accuracy and reliability with the advances in the aerodynamic models. The advances in the numerical simulations and the evaluation of the results will finally provide guidelines for the system design in terms of specific component characteristics.
The details of the activities are summarized below:
• Task 1.1: Refinement and evaluation of 2D unsteady aerodynamics models for airfoils with control devices
• Task 1.2: Development of advanced wake model
• Task 1.3: Coupling of 2D unsteady airfoil model with wake model and simulations of verification test cases
• Task 1.4: Development of engineering model for unsteady aerodynamics of rotors with distributed load control devices
• Task 5.1: Wind tunnel tests at various steady and dynamic angle of attack and flap motion cases
• Task 5.2: Wind tunnel tests at various extreme (gust) wind input cases
• Task 6.1: Integration of results into design recommendations for involved technology and tools
• Task 6.2: Various outreach activities
• Task 7.1: Advanced training in unsteady aerodynamics
• Task 7.2: Development of project management and proposal writing skills
Task 1.1 has provided a verified model to be utilized in Task 1.2. Activities in task 1.2 have contributed to the development and verification of the unsteady wake model with two active device concepts implementations for the case of a wing and for the case of a three-blade rotor. The model is used in an analysis in Task 1.3 with the target of achieving Milestone 1.1 'Investigation of improved predictions using higher fidelity coupled unsteady aerodynamics model'. The resulting activities with the continued Task 1.4 has been compiled in Deliverable 1.1 ' Report on the investigations using a higher fidelity coupled model and the derived engineering models for the unsteady aerodynamics of wind turbines rotor with distributed load control features'. Tasks 5.1 and 5.2 with the target of achieving Milestone 5.1 ‘Wind tunnel results for a blade section with a load control device at various motion and inflow conditions’ are completed. The results have been disseminated in Deliverable 5.1 ‘Report on wind tunnel results of the blade section with the control device’.
The expected results of the research activities consist primarily of the (1) evaluation of the benefits in accuracy and reliability with the advances in the aerodynamic models. The benefits will be demonstrated through the (2) results acquired from the improved full aeroelastic calculations in various operating conditions. Moreover, it is expected that (3) the implementation of integrated control approaches and inflow sensing will further improve the system performance in terms of both load reduction and power enhancement. The advances in the numerical simulations and the evaluation of the results will finally provide (4) guidelines for the system design in terms of specific component characteristics.