Passive Hypersonic Transition Control by Means of Ultrasonically Absorptive Thermal Protection Materials (UAT)

Abstract

A temperature stable porous C/C-SiC based material was successfully developed, acoustically characterized, experimentally tested and numerically modeled. The new generation ultrasonically absorptive material extents the applicability of the material towards an Ultrasonically Absorptive Thermal Protection System (UAT). In summary, the results have shown that the properties of the material can be adapted both by changing the CFRP production process and by changing the resin system. The new UAT material was successfully integrated and instrumented into a 7 degree half angle cone for testing in the DLR High Enthalpy Shock Tunnel Goettingen (HEG) at Mach 7.4. The tests ultimately confirmed the strongly increased absorber performance compared to the original C/C. Second mode instabilities were found to be strongly damped, making the detection of the waves above the porous surface very challenging. The increased absorber performance led to a strong delay of boundary layer transition which was the main purpose of the project.

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Document Details

Document Type
Technical Report
Publication Date
Jun 10, 2020
Accession Number
AD1108196

Entities

People

  • Alexander Wagner

Tags

Communities of Interest

  • Air Platforms
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Absorption
  • Absorption Coefficients
  • Acoustic Properties
  • Boundary Layer
  • Boundary Layer Transition
  • Computational Fluid Dynamics
  • Fluid Dynamics
  • Fluid Mechanics
  • Interferometers
  • Materials
  • Measurement
  • Mechanical Properties
  • Resin Transfer Molding
  • Shock Tunnels
  • Two Dimensional
  • Wind Tunnel Models
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Fluid Dynamics.
  • Fluid Mechanics and Fluid Dynamics.
  • Reinforced Composite Materials

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Boundary Layers
  • Hypersonics - Hypersonic Flow