Abstract
The impact of aerodynamic flow upon the performance of an airborne optical system is becoming a critical issue in the development and engineering of IR electro-optic systems. The analysis of this impact is now in the state of the art of IR electro-optic system research. Significant effort has been made on this issue during recent years1,2. In this work we describe a novel technique for aero-optic calculations. The technique is based on commercially available software. In this work CodeV is the optical ray tracing code and Fluent is the Computational Fluid Dynamics (CFD) code. The synergetic combination between the output of the CFD code and optical software leads to the development of the method. The optically relevant data from the CFD results is transformed into index of refraction field and introduced as an input to the optical code. It is important to note that the data must not necessarily be presented in an analytical form; rather it is introduced in the most general form - as a discrete set of values located at a non-uniform grid of points. The modified quadratic Shepard method3 has been adopted for the data interpolation. This enables a simple interface with virtually any software output. Such compatibility ensures that the technique can be easily extended for the solution of a whole spectrum of optical problems that involve arbitrary index of refraction changes in the bulk and arbitrary optical surface shapes. For example image quality degradation caused by dome heating can be easily assessed. Both index of refraction changes of the dome and dome shape distortion being taken into account. Several numerical simulations demonstrating the technique are presented.
Original language | English |
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Pages (from-to) | 618-626 |
Number of pages | 9 |
Journal | Proceedings of SPIE - The International Society for Optical Engineering |
Volume | 4820 |
Issue number | 2 |
DOIs | |
State | Published - 1 Dec 2002 |
Externally published | Yes |
Event | Infrared Technology and Applications XXVIII - Seattle, WA, United States Duration: 7 Jul 2002 → 11 Jul 2002 |
Keywords
- Aero-optics
- Computational Fluid Dynamics (CFD)
- Gradient index ray tracing
- Mean-flow MTF
- Modified quadratic Shepard method
- Non-uniform grid interpolation
- User-defined surface ray tracing
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering