WASHINGTON UNIV SEATTLE AEROSPACE AND ENERGETICS RESEARCH PROGRAM
The mass flow characteristics and optical qualities of axisymmetric free-jet aero-windows with passively induced swirl were studied for applications to free electron lasers. The aerowindows considered are axial supersonic flows from free-jets of various sizes. Mass flow rates through the nozzles are measured and compared to measured non-swirled flow rates and theoretical values. The effect of nozzle size on swirl induction is studied. Optical qualities are measured in the far field in the laboratory and compared with optical measurements from the non-swirled cases. The optical results for swirling flow shows weak defocusing and good Strehl ratios in contrast to focusing effects and good Strehl ratios for non-swirled flow.