The aim of this work is to investigate schlieren image correlation velocimetry for flow field quantification of gaseous
jet injection in non-manipulable apparatus like flow chambers. Such flow cases often struggle using tracer-based
methods: Seeding particles may locally cause technical problems, or the plant design prevents principal opportunity
of tracer adding, both of which lead to a reduced method repertory. This is specifically the case under flow conditions,
where contamination of apparatus internals by seeding particles should be avoided completely.
Therefore, in this paper we explore a seedingless, refraction-based method to quantify the velocity field of a jet plume.
As experimental flow case we examine a transient jet release into a closed compartment under nearly atmospheric
conditions. For simplification and greater clarity, the laboratory model geometry is kept essentially two-dimensional,
thus we chose a flat-jet nozzle as injection device. The experimental investigations cover high speed schlieren imaging
and laser sheet visualization followed by digital image correlation. Combining the traditionally qualitative schlieren
approach for flow visualization with Fast Fourier Transform and cross-correlation algorithms, we calculated the
velocity vector field of an unsteady jet plume formation. Furthermore, we determined the axial jet velocity profile at
steady state conditions. Our research findings highlight the applicability of schlieren image correlation velocimetry to
spatially quantify gaseous jet formation at encased flow sections. Concluding, the results coincide with data from
particle image velocimetry measurements and point out the potential of expanding flow diagnostics to hitherto hardly
explored (industrial) flow cases.