Ecology

Findings from Eindhoven University of Technology in Fluid Mechanics Reported

  2012 JUN 22 (VerticalNews) -- By a News Reporter-Staff News Editor at Ecology, Environment & Conservation -- Data detailed on Fluid Mechanics have been presented. According to news reporting from Eindhoven, Netherlands, by VerticalNews journalists, researchers stated "The thermal bar-a hydrodynamic phenomenon, arising in natural basins due to successive changes of the water temperature across the temperature of maximum density (T-m, which is close to 4 degrees C)-has been studied in laboratory experiments and by numerical simulations. The experiments were performed in a rectangular tank with an inclined bottom, filled with water with initial temperature T-0 < T-m and then heated at the surface."

  The news correspondents obtained a quote from the research by the authors from the Eindhoven University of Technology, "During the heating a basin-wide circulation develops, consisting of down-slope cascades in regions where T< T-m, a subsurface off-shore jet in the region where T> T-m, and a compensating flow at intermediate depths towards the shallow part of the tank, supplying both off-shore flows with waters from deeper regions. Analysis of the water temperature and density fields as well as the currents has revealed that the location of the convergence zone of the surface current (when formed) does not coincide with that of the T-m-isotherm. The thermal bar front is typically understood as a convergence zone near the 4 degrees C-isotherm, formed due to the effect of cabbeling. Our experiments demonstrate, however, that the front is associated with the leading edge of the subsurface current. The increasing distance between the 4 degrees C-isotherm and the subsurface jet has been recorded in the laboratory experiments. Numerical simulation results corroborate the laboratory experiments. A scaling analysis predicts the speed of propagation of this frontal zone to be U similar to [g x Lambda rho/rho xH](1/2), where H is the depth (increasing with time) of the upper thermo-active layer, rho(0) a reference density, and Delta rho is the characteristic horizontal density difference across the front."

  According to the news reporters, the researchers concluded: "A combined analysis of laboratory, field and numerical data has corroborated this law."

  For more information on this research see: On the fine structure of the thermal bar front. Environmental Fluid Mechanics, 2012;12(2):161-183. Environmental Fluid Mechanics can be contacted at: Springer, Van Godewijckstraat 30, 3311 Gz Dordrecht, Netherlands. (Springer - www.springer.com; Environmental Fluid Mechanics - www.springerlink.com/content/1567-7419/)

  Our news journalists report that additional information may be obtained by contacting N. Demchenko, Eindhoven University of Technology, Dept. of Phys, NL-5600 MB Eindhoven, Netherlands.

  Keywords for this news article include: Europe, Eindhoven, Netherlands, Fluid Mechanics

  Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2012, NewsRx LLC