The present numerical analysis and experiments attempt to characterize purge air systems applicable to gas turbine engine optical sensors, with emphasis on 'scrubbing' type purge systems employing contaminated compressor bleed air. The primary particle-deposition mechanism is found to be the eddy diffusion of submicron-sized particles, followed by the turbulent deposition and inertial impact of particles larger than 1 micron in aerodynamic diameter. Large, nonsticky particles are easily removed by a purge air system due to the exertion of the fluid drag force's exertion on a larger projection area; nevertheless, a virtual impactor has had to be incorporated in order to remove large, sticky particles.
AIAA, ASME, SAE, and ASEE, 24th Joint Propulsion Conference
- Pub Date:
- July 1988
- Optical Measuring Instruments;
- Turbine Engines;
- Computerized Simulation;
- Instrumentation and Photography