The near-field flow of an axisymmetric jet in a cross-stream

A flow field was established in a wind tunnel with uniform flow and low turbulence. Measurements of a three dimensional turbulent flow concerned only the case when there is no buoyancy or density stratification. The range of measurements included the flow upstream of the jet, the deflected jet and the wake of the cross stream produced downstream of the jet. Results show that there is considerable doubt that mathematical models of a jet in a cross stream based on some form of self-preservation relations will yield satisfactory results, at least in the development region from the jet origin until the flow reaches the state of the Beltrami flow. Also, the results proved that the entrainment process is an asymmetric phenomenon, and consequently models based on uniform and linear entrainment are questioned.