Limit-cylcle-oscillation simulations of Aerostabil windtunnel experiments II

Abstract

A series of windtunnel experi- ments conducted in the Transonic Windtunnel Göttingen (TWG) al- lowed the observation of Limit- Cycle-Oscillations of a backwards- swept, clean wing for a certain transonic parameter range. As additional feature the Aerostabil wing model shows cambering ef- fects, which have a strong in uence on transonic aerodynamics. This paper is following [13] and in more detail [14]. In these re- ports first simulation results em- ploying computation uid dynam- ics (CFD) and detailed computa- tional structural mechanics (CSM) of the AEROSTABIL experiment have been shown. But the struc- tural modelling has been limited to one dynamic degree of freedom. In this paper the structural rep- resentation is expanded to 2 dy- namic degrees of freedom which al- low a better agreement to the ex- perimental data. The LCO mech- anism is hereby confirmed: Strong shock movement leads to aerody- namic nonlinearities.