Thermal and solutal analyses of Reiner–Rivlin nanofluid with double diffusion and higher-order slip effects

Nanofluids containing nanoparticles and motile microorganisms have significant potential for enhancing heat transfer in engineering systems (e.g., heat exchangers and automotive cooling systems). This study examines heat and mass transfer in a double-diffusive bioconvection flow of a Reiner–Rivlin nanofluid under higher-order slip boundary conditions, including a suspension of motile microorganisms to enhance nanoparticle stability. The mathematical model incorporates the nanoparticle concentration equation, as well as nonlinear thermal radiation, an external heat source, and a chemical reaction, and is solved via a shooting method. Results indicate that slip at the surface significantly enhances both heat and mass transfer; additionally, higher Dufour and Lewis numbers increase the solutal concentration.