0

Full Content is available to subscribers

Subscribe/Learn More  >

Thermal Deformation Prediction and Measurement of Space Optical Systems

[+] Author Affiliations
Mark I. Scott, Mitra N. Sexton, David M. Stubbs, Ab Hashemi

Lockheed Martin Advanced Technology Center

Paper No. IMECE2005-80174, pp. 39-47; 9 pages
doi:10.1115/IMECE2005-80174
From:
  • ASME 2005 International Mechanical Engineering Congress and Exposition
  • Heat Transfer, Part B
  • Orlando, Florida, USA, November 5 – 11, 2005
  • Conference Sponsors: Heat Transfer Division
  • ISBN: 0-7918-4222-3 | eISBN: 0-7918-3769-6
  • Copyright © 2005 by ASME

abstract

A computational and experimental study of the thermal and thermally induced deformation of a plano mirror undergoing mW heat loading was performed to verify the capability to model the response of a representative imaging optic on the Space Interferometry Mission (SIM) spacecraft. Novel state of the art experimental and computational techniques provided milliKelvin and picometer precision in temperature and deformation prediction and experimental measurement. Mirrors of two different substrates, initially at ambient temperature under vacuum, were subjected to a thermal loading profile representing flight-like and overdrive thermal disturbance conditions. The experimental setup measured milliKelvin level temperature changes and picometer level deformation responses. I-deas / TMG was used to generate an integrated model to predict milliKelvin level changes in temperature of the mirror and picometer level deformation responses of the mirror surface. This paper focuses on the thermally induced deformation modeling and correlation to experimental data for the optical system. Comparison between experimental results and computational models for the deformation aspects of the test agreed well for the fused silica test mirror. In particular for the flight-like regime of primary interest, agreement between the experimental deformations and computational deformation results was within 18%. However the experimental results for the deformation of the Zerodur mirror presented challenges in prediction by the computational models. This is partly attributed to the low value of Zerodur CTE which affects numerical precision and partly due to non-homogeneity of the CTE which is neither modeled nor measured. Bi-material affect of coating was also investigated and found to be a potential source of discrepancy. Further studies regarding computational methods for Zerodur deformation are planned.

Copyright © 2005 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In