Adaptive DDES of a Vertical Tail/Rudder Assembly with Active Flow Control

PI Kenneth Jansen, University of Colorado Boulder
Co-PI Michael Amitay, Rensselaer Polytechnic Institute
Jed Brown, University of Colorado Boulder
Alireza Doostan, University of Colorado Boulder
John Evans, University of Colorado Boulder
John Farnsworth, University of Colorado Boulder
Michel Rasquin, University of Colorado Boulder
Onkar Sahni, Rensselaer Polytechnic Institute
Mark Shephard, Rensselaer Polytechnic Institute
Cameron Smith, Rensselaer Polytechnic Institute
Philippe Spalart, The Boeing Company
Edward Whalen, The Boeing Company

Time-averaged pressure is shown on a deflected rudder of a vertical tail in the area surrounding a single active jet. Time-averaged streamlines colored by vorticity magnitude are also shown. Together, this demonstrates the low pressure region created outboardof a single active jet by a large, oblique vortical structure that extends from the active jet downstream, outboard, and thus across the pathsof other jets (inactive in this case).

Project Summary

This project combines a highly scalable computational fluid dynamics solver with anisotropically adapted unstructured grids to enable flow simulations of unprecedented scale and complexity on Theta, gaining insight into questions of 3D active flow control.

Project Description

This project seeks to advance detached eddy simulations in aerodynamic flow control. The simulations will exploit anisotropic adaptive unstructured grids to match mesh length scales precisely to solution requirements which, together with a solver that has already scaled to more than3millionprocesses, will allow a dramatic advance in computational modeling and associated scientific and engineering insight.

Building on previous allocations, these simulations will compare, at high Reynolds numbers, synthetic and sweeping jets with 24, 1, and 0 active jets. These parameter variations reach one quarter magnitude of flight conditions,which will give critical insight required forAurora to carry out the first-ever high-Reynolds-number delayed detached eddy simulatio. This project is economically motivated by the goal of redesigning control surfaces to reduce their size.

The vertical tail is sized to handle an engine-out condition which requires it to be much larger than what is needed for all other conditions in the flight envelope. The economic impact is directly related to the size of the stabilizer since it is a significant contributor to drag in cruise where much of the fuel is expended.