Numerical simulation of free cross-shaped jet

Abstract

Numerical simulation of a turbulent cross-shaped orifice jet using the SST kω model is compared with measurements. The SST kω model is able to predict the axis-switching phenomenon. The initial boundary layers are lower than reference values and turbulent kinetic energy is over predicted. The flow expansion in the minor plane and flow contraction in the major plane are more pronounced and the potential core length is overestimated generating a delay on the streamwise maximum velocity decay. However, satisfactory predictions of the flow transverse area and volumetric flow rate are observed and lead to good predictions of "mean flow radius" and "mean flow velocity" evolutions. We are interested in optimizing HVAC diffusers using the passive control of the jet induc-tion. The lobed perforated panel is an innovative diffuser among others. The obtained results show that the SST kω model is an efficient tool for quickly optimizing non-circular orifice design.