This paper deals with local flow characteristics of subsonic turbulent jets in the presence of a cross-flow. For the various types of jet considered (a cylindrical jet and coaxial jets) the experimental results concern the axes and the velocity profiles in the plane of symmetry of the flow. In the case of the cylindrical jet, the shape of the universal axial velocity profile is defined, as are the law of velocity decay along the axis and the laws of variation of the thicknesses of the jet. Finally, the existence of a link between the axis equation and the law of axial velocity decay in the zone of similarity of the velocity profiles is established.

Experiments of simultaneous absorption of carbon dioxide and helium, in transient absorption regimes, have been carried out in a gasliquid flume for stratified-type cocurrent flows. There was a need to improve a method of chromatographic analysis for helium and CO, titrations in the gaseous phase and the liquid phase; this led us to study simultaneous absorption of CO, and He independent of dynamic conditions. In addition the dominant wave characteristics were studied and the interfacial friction velocity was measured. It was confirmed that, for two gases presenting a large contrast in diffusivities, gas absorption rates are related directly to the physical properties of the gases. The mass transfer coefficient varies with the -1 / 2 exponent of the Schmidt number for a large interfacial stress and a clean interface whereas it varies with the -2 / 3 exponent for weaker winds.

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