Tailoring boundary geometry to optimize heat transport in turbulent convection
Number of Authors: 3
2015 (English)In: Europhysics letters, ISSN 0295-5075, E-ISSN 1286-4854, Vol. 111, no 4, 44005Article in journal (Refereed) Published
By tailoring the geometry of the upper boundary in turbulent Rayleigh-Benard convection we manipulate the boundary layer-interior flow interaction, and examine the heat transport using the lattice Boltzmann method. For fixed amplitude and varying boundary wavelength., we find that the exponent beta in the Nusselt-Rayleigh scaling relation, Nu - 1 proportional to Ra-beta, is maximized at lambda =lambda(max) approximate to ( 2 pi)(-1), but decays to the planar value in both the large (lambda >> lambda(max)) and small (lambda << lambda(max)) wavelength limits. The changes in the exponent originate in the nature of the coupling between the boundary layer and the interior flow. We present a simple scaling argument embodying this coupling, which describes the maximal convective heat flux.
Place, publisher, year, edition, pages
2015. Vol. 111, no 4, 44005
IdentifiersURN: urn:nbn:se:su:diva-122776DOI: 10.1209/0295-5075/111/44005ISI: 000362357500020OAI: oai:DiVA.org:su-122776DiVA: diva2:868468