A jet at an oblique angle to a cross-flow

Abstract

We present the results of a preliminary experimental investigation into the behaviour of non-buoyant oblique discharges in a moving ambient fluid. Light Attenuation techniques are employed to measure trajectory, spread and integrated dilution data. A series of experiments have been conducted where the angle between the discharge direction and that of the ambient motion varied from 0 to 90 degrees. The experiments confirm that the nature of the discharge in the strongly advected region is only a function of this discharge angle. For angles less than or equal to 20 ° trends in the data obtained in the strongly advected region resemble that of a Gaussian weak-jet. For discharge angles of 40 ° and above the variation in strongly advected data was consistent with that of an advected line momentum puff, where the local tracer and velocity fields resemble those of a vortex pair. However, for flows released at discharge angles between 20 ° and 40 °, the formation of a Gaussian weak-jet or an advected line momentum puff could not be clearly identified in the strongly advected region. A conceptual model based on a set of analytical solutions is outlined and this provides the basis for interpreting the experimental data. Lagrangian integral numerical models are also developed to aid in the interpretation of the data.