Radiator Heat Transfer by a Hot Flow

Description

This project uses ANSYS Fluent to simulate heat transfer inside a radiator using nanofluid flow, a core problem in nanofluid heat transfer modeling. The radiator operates by passing hot nanofluid through internal pipes while cold air flows over them, absorbing heat and carrying it to the surrounding environment. In this simulation, an Al2O3-water nanofluid enters at 0.1 m/s and 343.15 K through three internal pipes, while cold air passes over the pipes at 3 m/s and 293.15 K, with the goal of evaluating heat transfer performance in the presence of the nanofluid.

Methodology

The nanofluid is defined with a density of 1086.287 kg/m³, specific heat capacity of 3804.691 J/kg·K, thermal conductivity of 0.6672643 W/m·K, and viscosity of 0.00108236 kg/m·s. The 3D geometry is built in SpaceClaim as a symmetric half-model of the radiator to reduce computational cost, with air inlet/outlet sections on both sides and three internal pipes for nanofluid flow. The domain is meshed in ANSYS Meshing using an unstructured grid of 1,033,305 elements.

The simulation uses a steady, pressure-based solver with gravity neglected. Turbulence is modeled using the standard k-epsilon model with standard wall functions, and the energy equation is enabled. Boundary conditions specify velocity inlets for both air (3 m/s, 293.15 K) and nanofluid (0.1 m/s, 343.15 K), pressure outlets (0 Pa gauge) for both streams, coupled thermal walls between the internal pipe surfaces, and a zero-heat-flux condition at the bottom wall. The solution uses coupled pressure-velocity coupling with second-order discretization for pressure, momentum, energy, and turbulence quantities, initialized with standard methods at 293.15 K and 3 m/s x-velocity.

Conclusion

Results include 2D and 3D contours of pressure, velocity, and temperature, characterizing the heat transfer performance of the nanofluid-cooled radiator system.