Optimization and sensitivity analysis on axisymmetric motile microorganism flow of viscoelastic nanofluid over a spinning circular disk with a central composite model

Abstract

A robust statistical analysis is presented for the axisymmetric motile microorganism flow over a spinning disk. The bio-convective flow of non-Newtonian nanofluid over a circular stretching rotating disk is considered. As a novelty, the influence of thermal radiation and binary chemical reaction and activation energy are incorporated to enhance the study. The requisite transformation rules are adopted to get a suitable non-dimensional model of the problem under consideration. Further, traditional numerical technique with the help of shooting-based Runge-Kutta fourth-order is employed subject to the suitable surface conditions in the proposed model. The characteristics of these parameters affecting the flow phenomena are depicted through graphs. According to the physical interpretation of the results, the non-Newtonian parameter, in conjunction with the stretching parameter, does have a significant role in elevating the radial velocity profile. A faster chemical reaction rate causes a decrease in fluid concentration, and faster energy transmission is caused by thermal radiation. The higher degree of thermal radiation and the greater Biot number are associated with a considerable increase in the rate of heat transfer and also boost the temperature of the nanofluid. The rate of heat transmission is extremely sensitive to the Biot number. A robust statistical approach namely Response Surface Methodology based on a face-centered Central Composite Design model is prescribed for the optimized heat transfer properties using various factors. The regression analysis is conducted through analysis of variance and the sensitive analysis of these factors is also exhibited. The current numerical analysis has relevance in the bioengineering of organisms movement, gas turbines, processing of food, enzyme bio-metals, and oil recovery.

Keywords:

• Binary chemical reaction
• bioconvection
• central composite design
• radiative heat flux
• response surface methodology
• sensitivity analysis