Corrugated surface for polymerase chain reaction (PCR) process: Thermal Rayleigh-Benard instability

Abstract

Numerical investigation is performed to analyze natural convection heat transfer characteristics within a corrugated surface enclosure filled with fluid under the Rayleigh-Bénard (RB) instability. The impact of the geometric contribution associated with the convective RB effect, is analyzed to provide qualitative heat transfer and flow structure. Such thermal process is applying for improving the engineering Polymerase chain reaction (PCR) process to amplify a target DNA sample. The grid generation is used to transform the physical complex domain to a computational regular coordinate. The governing differential equations are discretized by Finite volume approach using a quadratic scheme approximation. The main objective of this work is to analyze the combined physical and geometric effects characterizing the corrugated enclosure, on the behavior of convective flow and to enlarge the active isothermal area favorable for the elementary process actions. Under the effect of the different control parameters defined by the dimensionless mathematical model, we demonstrate the existence of critical corrugations amplitude as a function of Ra-λ, describing the bifurcation from monocellular towards a bicellular flow. The active isothermal zone are identified, quantified and physical explanation and predictive expression were established.