Numerical investigation of unsteady effects in turbomachines

Numerical simulations using CFD methods allow targeted investigation and quantification of flows, with the choice of the physical model and boundary conditions of individual phenomena may can be better insulated than in an experiment. In this project, unsteady flows are investigated by varying the angle of attack airfoil under dynamic or velocity. The background of the project is to study and quantify the aerodynamic loads on vertical axis wind turbine (Darrieus turbines). The flow of these systems is inter alia characterized by a pronounced nonstationarity. Because of the kinematics of these airfoils, learn a complex superposition of the angle of attack and oscillating longitudinal movement. The design of vertical wind turbines with conventional approaches (eg "actuator disc" principle) is therefore not possible. The project aims to introduce more reliable models for the interpretation of vertical wind turbines. At the same time should be explored, what performance gains are possible by exploiting the dynamic effects on the wing. The methods used are based on current parameter models (multiple-streamtube model), which allow for low computational complexity vergleichseise quantitative information on the performance of such systems - because of the use of empirical data and numerous simplifications, however, with quite large uncertainties. In contrast, with detailed CFD methods and may reliable data are obtained. However, the computational cost for this is extremely high. To analyze the flow, these methods provide valuable data. These are used to improve the applicability and validity of models and parameters thus make better information design and optimization can be.

The project is funded under the program ProInno II.