Active Flow Control (AFC) and Insect Accretion and Mitigation (IAM) System Design and Integration on the Boeing 757 ecoDemonstrator

Abstract

This paper presents a systems overview of how the Boeing and NASA team designed, analyzed, fabricated, and integrated the Active Flow Control (AFC) technology and Insect AccretionMitigation (IAM) systems on the Boeing 757 ecoDemonstrator. The NASA Environmentally Responsible Aviation (ERA) project partnered with Boeing to demonstrate these two technology systems on a specially outfitted Boeing 757 ecoDemonstrator during the spring of 2015. The AFC system demonstrated attenuation of flow separation on a highly deflected rudder and increased the side force generated. This AFC system may enable a smaller vertical tail to provide the control authority needed in the event of an engine failure during takeoff while still operating in a conventional manner over the rest of the flight envelope. The AFC system consisted of ducting to obtain air from the Auxiliary Power Unit (APU), a control valve to modulate the system mass flow, a heat exchanger to lower the APU air temperature, and additional ducting to deliver the air to the AFC actuators located on the vertical tail. The IAM system demonstrated how to mitigate insect residue adhesion on a wing's leading edge. Something as small as insect residue on a leading edge can cause turbulent wedges that interrupt laminar flow, resulting in an increase in drag and fuel use. The IAM system consisted of NASA developed Engineered Surfaces (ES) which were thin aluminum sheet substrate panels with coatings applied to the exterior. These ES were installed on slats 8 and 9 on the right wing of the 757 ecoDemonstrator. They were designed to support panel removal and installation in one crew shift. Each slat accommodated 4 panels. Both the AFC and IAM flight test were the culmination of several years of development and produced valuable data for the advancement of modern aircraft designs.

Jet vectoring using secondary Coanda synthetic jets

“…Although the vertical tail of the aircraft is necessary during takeoff and landing, it is rarely necessary during horizontal flight and leads to the generation of drag. Thus, Alexander et al (2016) attempted to reduce the area Ryota KOBAYASHI * , Yuki WATANABE ** , Yu TAMANOI *** , Koichi NISHIBE **** , Donghyuk KANG † and Kotaro SATO † † of the vertical tail. If flying wings and distributed propulsion actuators are practically developed in the future, the rudder, which is a movable part, will be eliminated.…”

“…As an alternative to the rudder, a compact vertical tail with a propulsion system for practical application is expected to be developed very soon. To date, several fundamental studies on fluidic thrust vectoring using the primary jet and the secondary jet with a Coanda surface have been conducted, and various methods have been proposed (Alexander et al, 2016;Mason et al, 2002;Al-Asady and Abdullah, 2017;Dores et al, 2006;. Studies have also been conducted on the flow fields of jets flowing over the Coanda surface.…”

DES of a Slingsby Firefly Aircraft: Unsteady Flow Feature Extraction Using POD and HODMD

“…These decomposition methods also offer the possibility of flow forecasting in compressible flows (Rona and Brooksbank 2003), or other complex fluid flows (Howard et al 2017;Gardner et al 2019). The ability to forecast unsteady flows with POD or DMD may allow incorporation into an advanced flow control system for aerodynamic stall (Frankhouser et al 2015), or control other aerodynamic phenomena in-flight (Alexander et al 2016) unsteady wake, with evidence of a wake-tailplane interaction.…”

Active Flow Control of a Supercritical Airfoil and Flap with Sweeping Jets

“…In aerospace engineering applications, in 2016, Boeing successfully used a sweeping jet to enhance the control characteristics of the vertical tail on the 757 environmental protection verification machines [14]. Based on the success of this application, a lifting system using AFC combined with simple flaps was proposed.…”