Nanofluid in a Wave Sine Channel: Heat Transfer

Nanofluid Flow in a Wave Sine Channel, Heat Transfer Analysis, ANSYS Fluent CFD Simulation Training

Description

This project simulates the wave motion of a nanofluid within a sinusoidal channel using ANSYS Fluent, with the nanofluid defined as Al₂O₃-water containing nanoparticles at a 1% volume fraction. The thermophysical properties of this nanofluid mixture were derived from standard nanofluid property equations, using the base thermophysical properties of both water and the Al₂O₃ nanoparticles as inputs.

The nanofluid enters the channel at 300 K. Due to the channel's wavy geometry, the horizontal velocity of the incoming flow varies as a function of vertical position, defined through a custom velocity profile implemented as a UDF. Thermally, the channel's lower wall was assigned a constant heat flux of 320 W/m², while the upper wall was held at a constant temperature of 320 K.

The 2D geometry was designed in Design Modeler, representing a sinusoidal channel 4 m long and 1 m wide, with a wavelength of 2 m and peak-to-trough height of 0.4 m. The domain was meshed in ANSYS Meshing using a structured grid totaling 21,300 elements.

Methodology

Several assumptions were applied to the simulation: a pressure-based solver was used, the simulation was run under steady-state conditions, and gravitational effects were excluded.

Key simulation settings included:

• Viscous model: Laminar, with the energy equation enabled

• Boundary conditions: Velocity inlet defined via the UDF-based velocity profile at 300 K; pressure outlet at 0 Pa gauge pressure; upper wall held at a constant 320 K; lower wall assigned a constant heat flux of 320 W/m², both stationary

• Solution methods: Coupled pressure-velocity coupling, second-order pressure discretization, and second-order upwind schemes for both momentum and energy

• Initialization: Standard method, with 0 Pa gauge pressure, 0.0015 m/s x-velocity, 0 m/s y-velocity, and 300 K temperature

Conclusion

Results include 2D contours of temperature, pressure, and velocity throughout the channel, along with plots tracking pressure and velocity variation along a hypothetical horizontal line through the channel's midline. These results characterize how the sinusoidal wall geometry, combined with the nanofluid's enhanced thermal properties, shapes the resulting flow acceleration and heat transfer pattern as the nanofluid moves through the wavy channel structure.