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In this work, the application of a shear stress transport based-RANS/LES turbulence modelling approach on a fluid-structure interaction (FSI) benchmark is considered after a transient computation of turbulent flow over the configuration on an LES quality mesh is to be performed. Within the unsteady decoupled simulation the scale resolving method successfully produces complex unsteady eddy sizes behind the reference test case. At a subcritical Reynolds number, a numerical Strouhal number of 0.184 which is close to a reference value of 0.18 is demonstrated by the RANS/LES turbulence model. In this scenario, a rubber added on the back part of a fixed circular cylinder is treated as a rigid thin plate during the pure flow simulation. On the LES grid resolution, the shielding function resided in the hybrid limiter of the scale resolving formulation is found to be strong to safeguard the activation of the RANS mode in the near wall region where the demarcation line between the RANS and LES modes uniquely resembles the geometry. Moreover, in the FSI simulation resolved turbulence scales interacting with moving and deforming rubber immersed in the subcritical Reynolds number-turbulent flow are successfully captured by the hybrid modelling technique coupled with a structural solver under the coupling procedure of an implicit partitioned approach. Similar with earlier studies with different scale-resolving proposals on the same FSI case, a periodic oscillating motion of the rubber that is produced from a phase-averaging method is also demonstrated in this present investigation. Nevertheless, a non-physical deformation of the rubber in the spanwise direction occurs. The new FSI result is evaluated with existing results from earlier works as a pivotal basis for further researches, such as implementations of new mesh stiffness model and filter width.

Experimental results of a fully pulsed subsonic air jet issuing into the still surrounding air are reported in this paper. The intermittent flow containing a period of no flow between pulses due to the mechanically excitation was gauged by a single wire hot-wire anemometer operated in a constant temperature mode. A range of the Reynolds and Strouhal numbers of 1 × 104 < Re < 4 × 104 and 0.0064 < St < 0.0076 respectively was used to define the jets. Results of the traverse measurement agreed with earlier findings demonstrating strong effects of the excitation on the radial profiles of the mean axial velocity of the jet. Within the parameter ranges investigated, the pulsed jets were found to be significantly more spreading than steady jets. A less dispersive pulsed jet, however, appeared at a higher jet exit velocity. Strikingly, contradictory trends in the jet growth and entrainment at the higher and lower Reynolds number were seen as the lower Reynolds number does not produce a widening radial profile as a result of the increasing Strouhal number. From the axial measurements, the pulsed jets were characterized by the pulsed dominated- and high turbulence steady jet region in which their existences heavily relied on the magnitudes of the controlled parameters. A less fluctuating pulsed jet associated with the reduced magnitudes of aggregate turbulence intensity and relative turbulence energy however, appeared at an increased Strouhal number. Comparative studies with the existing results of non-circular orifice jets i.e cruciform, elliptic, and triangular jets are also reported to display the decay rates of centerline axial velocity and the spreading rates of the jets which benefit for the practical purposes.