It is shown that laminar thermal convection can drive a chain reaction of DNA replication. The convection is triggered by a constant horizontal temperature gradient, moving molecules along stationary paths between hot and cold regions. This implements the temperature cycling for the classical polymerase chain reaction (PCR). The amplification is shown to be exponential and reaches 100,000-fold ...

Magnetohydrodynamic mixing of two fluids in an annular microchannel is modelled as a twodimensional, laminar, convection-diffusion problem, and examined using asymptotic analysis and numerical simulation. The time T required for mixing of a plug of solute depends on the Peclét number Pe, and on the geometry of the annulus. Three scaling regimes are identified: purely diffusive, Taylordispersive...

Transient laminar natural convection regimes occurring in a thermal convection loop heated from below and cooled from above are investigated numerically for a wide range of Rayleigh numbers spanning the interval from 10 to 2.6 10. In the model system, the lower half of the loop is heated and maintained at a constant high temperature, while the upper half is cooled and maintained at a constant l...

In the present work, a theoretical model based on the integral formalism approach for both laminar and turbulent external free convection is extended to Newtonian nanofluids. By using an empirical model for computing nanofluid viscosity, a close attention is focused first on the way the heat transfer is modified by increasing the volume fraction of nanoparticles and then to the transitional thr...

Abstract In this paper a numerical study of natural convection stationary laminar heat transfers in horizontal ring between heated square inner cylinder and cold elliptical outer is presented. A Cu-water nanofluid flows through annular space. Different values the Rayleigh number volume fraction nanoparticles are studied. The system equations governing problem was solved numerically by fluent ca...

the paper numerically presents laminar forced convection of a nanofluid flowing in a duct at microscale. results were compared with both analytical and experimental data and observed good concordance with previous studies available in the literature. influences of brinkman and reynolds number on thermal and hydrodynamic indexes have been investigated. for a given nanofluid, no change in efficie...