PCM around a Corrugated Tube

Description

This project uses ANSYS Fluent to simulate solidification and melting of a phase change material (PCM) around a corrugated tube, applying the solidification & melting module to model latent heat storage behavior. PCMs absorb latent heat during melting (cooling their surroundings) and release it during solidification (heating their surroundings), making them valuable for thermal energy storage applications. This simulation uses paraffin as the PCM, examining how its phase evolves in response to heat transfer from a wavy-surfaced inner tube.

Methodology

The paraffin PCM is defined with a density of 150 kg/m³, specific heat capacity of 2000 J/kg·K, thermal conductivity of 0.2 W/m·K, and viscosity of 0.03499 kg/m·s. The geometry is built in SpaceClaim and meshed in ANSYS Meshing using a structured grid of 135,939 cells. The solidification and melting model defines the phase change, with a solidus temperature of 350.15 K, liquidus temperature of 358.15 K, and latent heat of fusion of 176,000 J/kg. A transient solver is used with a 1 s time step to capture the time-dependent phase change process.

Conclusion

Results, reported at 7000 s of simulation time, include contours of temperature, temperature gradient, pressure, and liquid fraction. The PCM's behavior tracks its temperature response: as it absorbs heat from the inner tube, it transitions from solid to liquid in the regions where temperature rises, consistent with the expected melting behavior driven by latent heat absorption.