RETRACTED: Applications of bioconvection for tiny particles due to two concentric cylinders when role of Lorentz force is significant (Retracted article. See vol. 20, 2025)

The bioconvection flow of tiny fluid conveying the nanoparticles has been investigated between two concentric cylinders. The contribution of Lorenz force is also focused to inspect the bioconvection thermal transport of tiny particles. The tiny particles are assumed to flow between two concentric cylinders of different radii. The first cylinder remains at rest while flow is induced due to second cylinder which rotates with uniform velocity. Furthermore, the movement of tiny particles follows the principle of thermophoresis and Brownian motion as a part of thermal and mass gradient. Similarly, the gyro-tactic microorganisms swim in the nanofluid as a response to the density gradient and constitute bio-convection. The problem is modeled by using the certain laws. The numerical outcomes are computed by using RKF-45 method. The graphical simulations are performed for flow parameters with specific range like 1 <= Re<5, 1 <= Ha <= 5, 0.5 <= Nt <= 2.5, 1 <= Nb <= 3, 0.2 <= Sc <= 1.8, 0.2 <= Pe <= 1.0 and 0.2 <=Omega <= 1.0. is observed that the flow velocity decreases with the increase in the Hartmann number that signifies the magnetic field. This outcome indicates that the flow velocity can be controlled externally through the magnetic field. Also, the increase in the Schmidt numbers increases the nanoparticle concentration and the motile density.