CRJ700 regional aircraft performances optimization using adaptive winglet systems

Abstract

Motivated by the impact of aviation on global warming, this thesis aims to show the advantages of equipping aircraft with adaptive winglets. For validation purposes, the study was applied to the CRJ700 regional aircraft. Indeed, the Research laboratory of active control, avionics and aeroservoelasticity (LARCASE) has a level D flight simulator for this aircraft. This tool is essential in this research because it allows to deliver flight data admitting a maximum error of 5% with the real flight data of the aircraft. Moreover, a geometric model of the CRJ700 aircraft was provided by the manufacturer Bombardier, allowing us to work with the exact original geometry of the aircraft. An adaptive winglet system was developed to be presented as a short-term solution to improve aircraft performance and thus reduce its fuel consumption. The winglet is one of the last parts to be assembled on an aircraft. Therefore, it was considered that changing conventional winglets to adaptive winglets should be relatively cost-effective from a production perspective. The adaptive winglet developed in this thesis rotates between -93 deg and +93 deg, considering that for an angle of 0 deg, the winglet is parallel to the horizon. To perform the aerodynamic analysis, a high-fidelity model was developed using the open-source software OpenFoam. A specific methodology was established to make the model fully parametric and convergent for all flight conditions tested, considering angles of attack between -2 deg and +4 deg, as well as Mach number up to 0.79 for an altitude of 30,000 ft. The aerodynamic model validated for all these flight conditions with high accuracy, for instance by admitting a maximum margin of error of 0.0026 for the drag coefficient estimation. Using this model, an aerodynamic study was conducted. Due to the computational cost, it was chosen to perform simulations for the winglet positions of -93, -73, -35, 0, 35, 73 and 93 deg, and to then predict the evolution of the aerodynamic coefficients for the intermediate winglet positions using interpolation methods. This methodology allowed the aerodynamic coefficients of the different winglet positions available between -93 and 93 deg to be studied, and for 35 flight conditions commonly used by the CRJ700 aircraft. It was found that for the same flight conditions the lift coefficient of an aircraft equipped with an adaptive winglet was significantly increased, while the drag coefficient was reduced compared to the original aircraft configuration. This demonstrated that for a given lift coefficient, an aircraft equipped with an adaptive winglet had a drag 2.65% lower than the drag of the same aircraft equipped with a fixed winglet. A performance study was then conducted to analyze the benefits in terms of fuel consumption using a model developed and validated at the LARCASE. A methodology was developed to isolate the aerodynamic contributions of the "wing-body" and "horizontal-tail" groupings of the aircraft from the global calculations, computed using the OpenFoam software. In addition, a method to calculate the downwash deviation angle of the fluid by the wing was developed. Using these data and methodologies, the advantages of equipping an aircraft with adaptive winglets can be confirmed, particularly with a climb time improved by 4.21% on average, fuel consumption reduced by 3.79% on average during climb and by 1.99% on average during cruise.

Date	29 Jun 2022
Original language	American English
Awarding Institution	École de technologie supérieure
Supervisor	Ruxandra Botez (Supervisor)