Double-diffusive stagnation point flow over a vertical surface with thermal radiation: Assisting and opposing flows

Area of Science:

• Fluid Dynamics
• Heat and Mass Transfer
• Nanotechnology

Background:

• Ensuring efficient heat and mass transfer is critical in many industrial processes.
• Nanofluids offer enhanced thermal properties for improved heat transfer applications.

Purpose of the Study:

• To investigate unsteady double-diffusive mixed convection boundary layer nanofluid flow near a stagnation point.
• To analyze the effects of Brownian motion and thermophoresis on heat and mass transfer characteristics.

Main Methods:

• Utilized Buongiorno's model incorporating Brownian motion and thermophoresis.
• Transformed nonlinear unsteady partial differential equations into ordinary differential equations using local similarity method.
• Numerically solved the equations using the Keller-Box method.

Main Results:

• Analyzed the influence of various parameters on velocity, temperature, and concentration profiles.
• Identified that negligible thermophoresis yields the highest heat transfer rate.
• Observed that increased thermophoresis and solutal concentration reduce nanoparticle Sherwood number, while Brownian motion increases it.

Conclusions:

• The study provides insights into nanofluid behavior under mixed convection, relevant for optimizing industrial heat and mass transfer.
• Buongiorno's model effectively predicts double-diffusive fluid characteristics for enhanced heat transfer.
• Findings have potential to advance designs in solar water heaters, electronics cooling, and other heat-intensive industries.