Thermal radiation impact on bioconvection flow of nano-enhanced phase change materials and oxytactic microorganisms inside a vertical wavy porous cavity

This work examines the bioconvection of nano-enhanced phase change materials (NEPCMs) and oxytactic mi-croorganisms in a vertical wavy cavity saturated by a porous medium. The novelty of this work is demonstrating the significance of wavy surface and thermal radiation on the bioconvection flow of NEPCMs and oxytactic microorganisms within a porous wavy cavity. Further, a novel attempt in achieving high-performance conduc-tivity by combining the NEPCM and oxytactic microorganisms during the bioconvection flow in a complex wavy cavity is examined. The dimensionless governing partial differential equations are discretized using the finite element method and the discrete nonlinear systems are handled using the adaptive Newtons method. The results showed the contributions of thermal radiation to enhancing the strength of streamlines. The undulation number of a wavy wall affects the bioconvection flow and contours of streamlines and heat capacity inside a wavy cavity. The Rayleigh number strengthens the streamlines and bioconvection flow. Increasing the Darcy parameter im-proves the isotherms, oxygen isoconcentration, and microorganisms isoconcentration. Consequently, the PCM shifts towards the right side of a cavity along with a growth in the Darcy parameter. The mean Nusselt number Nuavg and Sherwood number Shavg are altered by the involved physical parameters. Increasing Rayleigh's number from 103 to 106 augments Nuavg by around 153.8% and declines Shavg by 33.3%.