The initial findings of an ongoing study of negatively bouyant jet (or plume) behavior are described. the motivation for this research is to quantify the dynamics of the exit snow plume from displacement and rotary snow plows. the effects of injection angle and cross flow on the jet (or plume) behavior were of particular interest in this phase of the study. a water tow tank was used for the experiments, in which the exit jet was towed through quiescent water at a constant velocity. photographic records of the jet (or plume) structure were used to measure the jet (or plume) dimensions. dimensional reasoning yielded a set of dimensionless parameters that correlated the jet or plume length scales over a wide range of the experimental parameters. three flow regimes have been identified, which depend on the froude number, f sub 0, of the cross flow: f sub 0 << 1, negligible cross flow; 0 < f sub 0 < 1, weak cross flow; and f sub 0 > 1, strong cross flow; where f sub 0 . u sub 0/(g' sub 0)to the 1/2 power, u sub 0 is the cross-flow velocity, g' is the reduced gravity, and rsub 0 is the jet radius. correlations of the measured length scaleswith f sub 0 were determined for all three flow regimes. this paperappears in transportation research record no. 1304, highway maintenance operations and research 1991.
Samenvatting