Optimization of High-Speed White Beam X-ray Imaging for Spray Characterization

Abstract

<p>The near-field region of a spray has a significant impact on the downstream dynamics. However, the near-field region remains one of the most difficult areas to characterize due to its optical density to visible light. One of the methods used to probe the near-field region is high-speed white beam (broad-spectrum) X-ray radiography, which generates path integrated, time sequenced images of the spray. While white beam imaging is effective at probing the near-field region, high intensity synchrotron sources are required to acquire high-speed time-resolved image sequences. The drawback to a synchrotron source is it emits a significant portion of its X-ray spectrum at energies that are minimally attenuated by most sprays. This paper will examine the various parameters that can be tuned to improve the characterization of sprays with white beam X-rays, and will assess their effects on the X-ray image quality. A representative spray conditions will be shown using a canonical coaxial gas-liquid atomizer imaged at the 7-BM beamline of the Advanced Photon Source at Argonne National Laboratory.</p>