Efficient Design Exploration of Nacelle Chine Installation in Wind Tunnel Testing

Abstract

Design exploration of a nacelle chine installation was crried out. The nacelle chine is a device to improve the stall performance when multi-element high-lift devices were deployed. In this study, an efficient design process using Kriging surrogate model was proposed to decide the nacelle chine installation point in wind tunnel tests. The design process called ‘efficient design optimization (EGO)’ was conducted in the wind tunnel testing of JAXA high-lift aircraft model at JAXA Large-scale Lowspeed Wind Tunnel. The objective function for the EGO was to maximize the maximum lift. The installation points of the chine on the engine nacelle in the axial and chord-wise direction were designed, while the geometry of the chine was fixed. Through the design process in the wind tunnel test, an accurate surrogate model of the maximum lift by the chine location was efficiently obtained using expected improvement values as a criterion to select additional evaluation points. This method makes it possible not only to improve the accuracy of the response surface but also to explore the global optimum efficiently. Through this test, EGO process could be successfully applied to the design based on the wind tunnel test result.