Accession Number:

ADA238159

Title:

Ablative Heat Shield Studies for NASA Mars/Earth Return Entry Vehicles

Descriptive Note:

Master's thesis,

Corporate Author:

NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s):

Report Date:

1990-09-01

Pagination or Media Count:

121.0

Abstract:

A material that behaves likes a glassy ablator on the surface, has a low thermal conductivity, is structurally tough, lightweight, and is in some sense reusable, would be desirable for the protective heat shield used on Earth entry vehicles. A material for this purpose has been developed that uses silicon dioxide fused quartz in a fibrous packed matrix, forming blocks which can behave as a glassy ablator on the surface when subject to very high surface heat fluxes. These fibrous silicon dioxide blocks are called Reusable Surface Insulation RSI. The primary constituent of the RSI material is silicon dioxide, but may contain other compounds e.g. alumina borosilicate to affect the thermal and physical properties. The research performed in this thesis is to determine the ablative behavior of ceramic RSI materials in a hypersonic high enthalpy flow that is used to simulate entry into Earth atmosphere. Actual arc jet experiments were performed to measure mass loss, melt run off, and fiber collapse of these materials and compare the experimental results with predicted theoretical values. The tests were performed to ascertain if RSI type materials could be used for entry vehicles proposed in NASA Mars missions.

Subject Categories:

  • Ceramics, Refractories and Glass
  • Unmanned Spacecraft

Distribution Statement:

APPROVED FOR PUBLIC RELEASE