Dense, Vertical Jets with Two Opposing Buoyancy Components

The height to which dense, vertical jets with two opposing buoyancy components rise was investigated experimentally. In the experiment, the dense, vertical jets were produced by using the temperature difference between the jet at the nozzle and the surroundings as the positive buoyancy component, and by using common salt and CuSO₄ alternatingly for the negative buoyancy component. Based on a dimensional argument, it was found that the three nondimensional parameters of (1) the ratio of the jet height to the nozzle diameter, H/r_j, (2) the internal Froude number, Fr, and (3) the density ratio, R, all govern the behavior of the jet. The data were well correlated when H/r_jFr was plotted against against 1/R in the range of 0 ≤ 1/R ≤ 0.9, showing that H/r_jFr tends to fall with an increase of 1/R. A least square fitting of the data yielded the explicit form of the jet height to be