Characterization of three-dimensional dense spray visualization techniques

Abstract

Resolving the dense liquid core structure of sprays has required the development of novel imaging techniques to more thoroughly examine complex multiphase fluid phenomena. In the current work, we discuss complementary methods of investigating the dense core region of the spray, including measurements of the exterior three-dimensional surface topology using structured light and interior liquid mass distributions using X-ray radiography and Xray computed tomography. Three-dimensional shape measurement data were collected using a 3-D machine vision system. The information from this technique is then used to compute the exterior three-dimensional surface of the spray, which captures the timeresolved motion of impact waves generated by instabilities leading to primary breakup. Data from the Advanced Photon Source at Argonne National Laboratory and an X-ray tubesource are compared to evaluate the accuracy of internal liquid mass distribution measurements from time-averaged X-ray radiography and computed tomography. Measurements with a tube source were also extended using a flash X-ray tube-source and two simultaneous orthogonal detection systems for spray imaging of a gas-centered swirl coaxial injector. These complementary techniques are used to reveal the exterior and interior details of primary break-up dynamics in dense sprays of practical interest.