Velocity Statistics of a Fully Pulsed Round Jet in Streamwise Direction

Keywords: hot-wire anemometer, pulsed jet, Reynolds number, Strouhal number.

Abstract. In this paper, statistical quantities of a fully pulsed round jet along the jet centerline are
reported. A range of the Reynolds (1.5 x 104 < Re < 4 x 104) and Strouhal (0.0064 < St < 0.0076)
numbers is used to generate the jet. Physically this unsteady jet produces a series of distinct pulses
due to the excitations. The mechanically excitations lead to the appearance of pulse dominated and
high turbulence steady jet region in which their existence is of a strong dependence on the level of
the controlled parameters. After the pulse merging completes the pulsed jet alters to a selfpreserving
steady jet with a significantly higher turbulence intensity. Under a constant mass flow
rate the pulsed jet tends to be more fluctuating at a less intense pulsation thus permitting the
endurance of the normalized periodic component and a more rapid velocity decay in the pulsedominated
region.