Inclined Dense Jets in Flowing Current

Abstract

An extensive series of experiments on the characteristics of inclined and vertical dense jets discharged into a uniform crossflow of various speeds and directions is reported. The inclined jets were maintained at 60° to the horizontal and the results for terminal rise height, and dilutions at the terminal rise height and impact points are compared to those for vertical jets. For discharges into stagnant ambients, it is found that the effect of source volume flux should not be neglected for jet Froude numbers less than about 25. Empirical equations to predict dilution and rise height based on dimensional and length scale arguments are presented. The dilution of an inclined jet increases as the angle to the current increases. Dilutions for inclined jets discharging into the crossflow are lower than for a vertical jet and dilutions for discharges with the crossflow are generally higher. Applications to design are discussed, and it is found that the inclined jet is generally preferable to the vertical jet. This is because of the lower rise height of the inclined jet, the much higher dilution under stagnant conditions, and the horizontal momentum given to the wastefield.