  It is of special interest in some conventional chemical technologies to
provide either fast mixing of reagents or rapid quenching of final chemical
product. One of most promising techniques to achieve it is mixing of multiple
jets radially injected in crossflow (JIC) of cylindrical duct when jets impinge
and form a jet flowing towards a crossflow. As result of an interaction of
counter-flowing jet and confined crossflow, a recirculation flow zone (RFZ)
upstream of jets injection plane (JIP) is formed (see Fig.1). Of valuable
importance is to reveal upstream behavior of developed counter-flowing jet in
confined crossflow in order to estimate an extreme RFZ size where jets are
diluted and mixed under non-equilibrium conditions.
