In this section
@article{Van:2015:10.1017/jfm.2015.534,
author = {Van, Reeuwijk M and Craske, J},
doi = {10.1017/jfm.2015.534},
journal = {Journal of Fluid Mechanics},
pages = {333--355},
title = {Energy-consistent entrainment relations for jets and plumes},
url = {http://dx.doi.org/10.1017/jfm.2015.534},
volume = {782},
year = {2015}
}
TY - JOUR
AB - We discuss energetic restrictions on the entrainment coefficient α for axisymmetric jets and plumes. The resulting entrainment relation includes contributions from the mean flow, turbulence and pressure, fundamentally linking α to the production of turbulence kinetic energy, the plume Richardson number Ri and the profile coefficients associated with the shape of the buoyancy and velocity profiles. This entrainment relation generalises the work by Kaminski et al. (J. Fluid Mech., vol. 526, 2005, pp. 361–376) and Fox (J. Geophys. Res., vol. 75, 1970, pp. 6818–6835). The energetic viewpoint provides a unified framework with which to analyse the classical entrainment models implied by the plume theories of Morton et al. (Proc. R. Soc. Lond. A, vol. 234, 1955, pp. 1–23) and Priestley & Ball (Q. J. R. Meteorol. Soc., vol. 81, 1954, pp. 144–157). Data for pure jets and plumes in unstratified environments indicate that to first order the physics is captured by the Priestley and Ball entrainment model, implying that (1) the profile coefficient associated with the production of turbulence kinetic energy has approximately the same value for pure plumes and jets, (2) the value of α for a pure plume is roughly a factor of 5/3 larger than for a jet and (3) the enhanced entrainment coefficient in plumes is primarily associated with the behaviour of the mean flow and not with buoyancy-enhanced turbulence. Theoretical suggestions are made on how entrainment can be systematically studied by creating constant- Ri flows in a numerical simulation or laboratory experiment.
AU - Van,Reeuwijk M
AU - Craske,J
DO - 10.1017/jfm.2015.534
EP - 355
PY - 2015///
SN - 0022-1120
SP - 333
TI - Energy-consistent entrainment relations for jets and plumes
T2 - Journal of Fluid Mechanics
UR - http://dx.doi.org/10.1017/jfm.2015.534
UR - https://www.cambridge.org/core/journals/journal-of-fluid-mechanics/article/energyconsistent-entrainment-relations-for-jets-and-plumes/801E85FC39221592D35D2C2A95BD5C0A
UR - http://hdl.handle.net/10044/1/26767
VL - 782
ER -