Dynamic modeling of turbulent shedding effect on the 30-m primary mirror of GSMT

Guanpeng Xu; Mark S. Whorton; Yong X. Tao; Myung K. Cho

doi:10.1117/12.458038

Translator Disclaimer

30 January 2003 Dynamic modeling of turbulent shedding effect on the 30-meter primary mirror of GSMT

Guanpeng Xu, Mark S. Whorton, Yong X. Tao, Myung K. Cho

Author Affiliations +

Proceedings Volume 4840, Future Giant Telescopes; (2003) https://doi.org/10.1117/12.458038
Event: Astronomical Telescopes and Instrumentation, 2002, Waikoloa, Hawai'i, United States

Abstract

This paper presents a Navier-Stokes based numerical methodology for 3D unsteady viscous flow over a general mirror configuration. In this approach, the Reynolds averaged Navier-Stokes equations in finite volume form are solved unsteadily using Roe’s scheme on body fitted H-H type grid. A two-equation turbulence model was implemented. This method is three or five order accurate in space and first order accurate in time. The physical space modeled is a 120m×120m×120m region enclosing the primary mirror at the center. The inflow turbulence from the enclosure openings is represented by turbulence kinetic energy at the inflow boundary. The wind buffeting effect was studied by directly calculating flow field response to buffeting impinging wind. The unsteady pressure distribution on the mirror is extracted and analyzed for the amplitudes and frequencies of dynamic wind loading. The computational results are visualized to highlight the flow pattern, particularly on the mirror upper surface. Results are presented for a 30-meter aperture GSMT primary mirror. A 1:833 model of the GSMT primary mirror was tested in a water tunnel, in which the velocity distribution was measured using PIV technique. The preliminary experimental observation serves as qualitative validation of the simulation capability.

Citation Download Citation

Guanpeng Xu, Mark S. Whorton, Yong X. Tao, and Myung K. Cho "Dynamic modeling of turbulent shedding effect on the 30-meter primary mirror of GSMT", Proc. SPIE 4840, Future Giant Telescopes, (30 January 2003); https://doi.org/10.1117/12.458038

ACCESS THE FULL ARTICLE