Code-to-Code Comparison for the Blind-Test Activity of the Tiltaero Project

Abstract

The present paper illustrates the results obtained so far by CIRA, DLR, NTUA and ONERA during a blind-test activity performed in the framework of WP1 of the European research project TILTAERO (TILTrotor interactional AEROdynamics). The aim of the work package is to evaluate the capabilities of the prediction tools applied for the analysis of the interactional aerodynamics of a tilt rotor configuration. Two BEM methodologies, differing with respect to the wake modelling, an unsteady RANS and a quasi-steady RANS CFD methodologies have been applied by the authors for this purpose. The paper provides a synthetic description of the TILTAERO project and illustrates the main aspects of the blind-test activity. The main features of the numerical methodologies applied are also described. The analysis is performed by illustrating the numerical results obtained for three different test conditions of the TILTAERO wind tunnel mock-up in terms of quasi-steady, time-averaged and unsteady pressure distributions as well as quasi-steady, time-averaged and unsteady normal forces acting on the configuration. These results, obtained prior to the production and release of the relevant experimental data base, have provided useful indications of the complex interactional phenomenology.