You are here:
CONVECTION TANK EXPERIMENTS ON TOP-DOWN, BOTTOM-UP DIFFUSION
Citation:
Piper, M., J. Wyngaard, W. Snyder, AND R.E. Lawson, Jr. CONVECTION TANK EXPERIMENTS ON TOP-DOWN, BOTTOM-UP DIFFUSION. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/A-95/008.
Description:
Large-eddy simulation (LES) results indicate that scalar diffusion in the convective atmospheric boundary layer (CBL) has interesting properties. calar introduced into the bottom of the CBL with no flux through the top (bottom-up diffusion) has a radically different eddy diffusivity profile than a scalar introduced at the CBL top with zero flux through the surface (top-down diffusion). o test the LES results, we designed and implemented a set of experiments in a replica of the original Deardorff-Willis laboratory convection tank. e measured mean gradients and inferred flux profiles of two scalars, temperature and dye concentration, to calculate vertical profiles of the top-down and bottom-up eddy diffusivities. ur experimental results were in good agreement with the LES results.