Submerged Buoyant Jets in Quiscent Fluids

An integral-type analysis is developed for submerged buoyant jets discharged horizontally into quiescent homogeneous fluids. Equations for conservation of volume flux, buoyancy flux, and kinematic conditions are combined with three self-similarity assumptions and one entrainment assumption. The entrainment velocity is assumed to consist of two components: one is related to the initial jet momentum, the second to the buoyancy force, so that the constant entrainment coefficients obtained from studies of pure jets and pure plumes can be utilized. A closed-form solution is obtained which yields polynomials describing the trajectories of both round and slot jets and linear and parabolic relations for the dilution for round and slot jets, respectively. These relations compare favorably with experimental and numerical results reported by other investigators.