Instrumentation and Ground Testing of a Composite Elastic Wing Wind Tunnel Model

Abstract

The Goal of the Project GRETEL is to build a composite elastic wing wind tunnel model. This model incorporates morphing aerodynamical structures and is to be delivered for testing in the Large Low speed Facility (LLF) wind tunnel of DNW. In order to be allowed to be tested in a wind tunnel, a ground test is required to assure the integrity of the design of the wing. In this paper a short introduction to the overall setup of the model is given including an overview of integrated sensors. A short introduction into the different configurations of the wing to be tested is given as well as the rationale for the derived test-matrix of the ground tests. The mechanical setup for the ground tests is described. There are two main tests done, on the one hand the static tests of the wingbox, on the other hand the dynamic tests for determination of modal parameters of the model in its different configurations. The static tests are done to identify mechanical responses of the model as built and compare them to the predictions of the Finite Element simulations. The method to derive the boundary conditions, i.e. loads and deformations, for the static tests from the simulation is documented and discussed. The static tests are also used to calibrate the integrated strain gauges to enable load monitoring in the wind tunnel tests. First experimental results from the ground tests are shown and discussed, comparing them to predictions from the simulation.