Numerical Study of Ram Air Airfoils and Upper Surface Bleed-Air Control

Abstract

Natick Soldier Research, Development, and Engineering Center has been leading a Modeling and Simulation effort to develop high fidelity simulations of ram-air parachute systems to complement the design and analysis of new and existing airdrop systems. In this paper an unsteady numerical study of two-dimensional, rigid, ram-air sections with an array of upper surface bleed-air actuators is presented. Aerodynamic forces and lift-to-drag ratios of a modified Clark-Y ram-air airfoil are calculated from unsteady Reynolds-Averaged Navier-Stokes (RANS) simulations, using the Kestrel and Cobalt flow solvers. The flow fields exhibit a complicated cavity flow coupling with the airfoil profile. Variations in the locations and number of bleed air actuators and trailing edge deflection yield time averaged L/D values between 1.24 and 59.14, and strongly support the utility of the bleed air actuators for use as an enhanced lateral/longitudinal control mechanism. Additionally, these initial results emphasize the requirements for prudent mesh generation and the performance of unsteady calculations for ram-air canopy simulations.

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Document Details

Document Type
Technical Report
Publication Date
Jun 16, 2014
Accession Number
AD1015118

Entities

People

  • Adam Jirasek
  • Andrew J. Lofthouse
  • Juergen Seidel
  • K. Bergeron
  • Mehdi Ghoreyshi
  • Russell M. Cummings

Organizations

  • United States Air Force Academy

Tags

Communities of Interest

  • Human Systems

DTIC Thesaurus Topics

  • Actuators
  • Aerodynamic Forces
  • Computational Fluid Dynamics
  • Couplings
  • Deflection
  • Demographic Cohorts
  • Engineering
  • Flow
  • Flow Fields
  • Parachutes
  • Reliability
  • Simulations
  • Trailing Edges
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Aerial Delivery - Logistics and Supply Chain Management.
  • Aerodynamics/Aeronautics.
  • Fluid Mechanics and Fluid Dynamics.