Particle Image Velocimetry Measurements in Accelerated, Transonic Wake Flows

Abstract This paper reports on particle image velocimetry (PIV) measurements in compressible accelerated wake flows generated by two different central injector types, which are mounted a convergent-divergent nozzle. The injectors differ the extent of their trailing edge located either subsonic (injector A) or supersonic flow region B). In addition, undisturbed nozzle without is studied as reference case. PIV results reveal typical structures expected and B) flows. They further show that Reynolds stresses $$\mathrm {Re_{xx}}$$ Re xx {Re_{yy}}$$ yy significantly decay all three cases due to strong acceleration throughout Interestingly, case A, stays non-isotropic with {Re_{yy}}>\mathrm > also far downstream region. These were motivated lack velocity data needed validate numerical simulations. That why this additionally contains from (unsteady) Reynolds-averaged Navier-Stokes ((U)RANS) simulations investigated experimentally. URANS simulation A able accurately predict entire field periodic fluctuations at centerline. However, B, RANS underestimates centerline about $$4\%$$ 4 % .