Lattice Boltzmann Simulation of Energy Storage Using Nano Phase Change Materials for Potential Use in Electronics Cooling

Abstract

This study presents a hybrid numerical scheme that couples the Lattice Boltzmann Method (LBM) with the Finite Difference Method (FDM) to model Micro Phase Change Material (MPCM) suspensions in a minichannel, with the objective of enhancing electronics cooling. Within this framework, the LBM was employed to solve the continuity, momentum, and energy equations for the fluid domain, while a Lagrangian scheme replicates the motion of MPCM particles. The LBM is coupled with an FD solver to deal with the phase change phenomena within the microparticles. This hybrid coupling eliminates the necessity for any specific treatment in handling phase transitions and tracking phase interfaces. The proposed method is first evaluated on classic particle cases, demonstrating its ability to achieve four-way coupling. This coupling encompasses fluid and solid phases mutual influence, inter-particle interactions, and particle-wall collisions. Furthermore, the current model effectively adapted viscosity changes when integrating the microparticles, obviating the need of homogenous viscosity models. Subsequently, the potential of this novel approach is demonstrated on examining the influence of MPCM particles near-wall thermal interaction, considering three scenarios based on particle density: light (𝜌𝑝 < 𝜌𝑓), neutrally buoyant (𝜌𝑝 ≈ 𝜌𝑓) and dense (𝜌𝑝 > 𝜌𝑓) microparticles. The hybrid approach further enabled the investigation to reveal new insights into the impact of volume fraction across various flow regimes on the heat transfer coefficient in both the entrance and fully developed regions, as well as on the overall heat transfer coefficient, friction factor, and performance index from a Lagrangian perspective.

Date of Award	15 Dec 2023
Original language	American English
Supervisor	Anas Alazzam (Supervisor)