Single-shot volumetric laser induced fluorescence (VLIF) measurements in turbulent flows seeded with iodine

This work reports the experimental demonstration of single-shot visualization of turbulent flows in all three spatial dimensions (3D) based on volumetric laser induced fluorescence (VLIF). The measurements were performed based on the LIF signal of iodine (I-2) vapor seeded in the flow. In contrast to established planar LIF (PLIF) technique, the VLIF technique excited the seeded I-2 vapor volumetrically by a thick laser slab. The volumetric LIF signals emitted were then simultaneously collected by a total of five cameras from five different orientations, based on which a 3D tomographic reconstruction was performed to obtain the 3D distribution of the I-2 vapor in the target flow. Single-shot measurements (with a measurement duration of a few ns) were demonstrated in a 50 mm x 50 mm x 50 mm volume with a nominal spatial resolution of 0.42 mm and an actual resolution of similar to 0.71 mm in all three dimensions (corresponding to a total of 120 x 120 x 120 voxels). (C) 2015 Optical Society of America