dc.creator | Ball, Thomasina | |
dc.creator | Huppert, Herbert Eric | |
dc.creator | Lister, John Ronald | |
dc.creator | Neufeld, Jerome Anthony | |
dc.date.accessioned | 2017-03-27 | |
dc.date.accessioned | 2018-11-24T23:20:13Z | |
dc.date.available | 2017-07-05T11:46:59Z | |
dc.date.available | 2018-11-24T23:20:13Z | |
dc.date.issued | 2017-06-01 | |
dc.identifier | https://www.repository.cam.ac.uk/handle/1810/265188 | |
dc.identifier.uri | http://repository.aust.edu.ng/xmlui/handle/123456789/3568 | |
dc.description.abstract | The equilibration time in response to a change in flux from Q to $\Lambda$Q after an injection period applied to either a low-Reynolds-number gravity current or one propagating through a porous medium, in both axisymmetric and one-dimensional geometries, is shown to be of the form $\tau$ = Tf($\Lambda$) , independent of all the remaining physical parameters. Numerical solutions are used to investigate f($\Lambda$) for each of these situations and compare very well with experimental results in the case of an axisymmetric current propagating over a rigid horizontal boundary. Analysis of the relaxation towards self-similarity provides an illuminating connection between the excess (deficit) volume from early times and an asymptotically equivalent shift in time origin, and hence a good quantitative estimate of $\tau$ . The case of $\Lambda$ = 0 equilibration after ceasing injection at time T is a singular limit. Extensions to high-Reynolds-number currents and to the case of a constant-volume release followed by constant-flux injection are discussed briefly. | |
dc.language | en | |
dc.publisher | Cambridge University Press | |
dc.publisher | Journal of Fluid Mechanics | |
dc.title | The relaxation time for viscous and porous gravity currents following a change in flux | |
dc.type | Article | |