Gas-liquid two-phase flow simulation for thermal insulation effect by foam

Sitompul, Y.  ; Aoki, Takayuki*; Watanabe, Seiya*; Sugihara, Kenta ; Takaki, Tomohiro*

Foam formation and its thermal insulation properties are crucial in various industries. This study presents a numerical approach using the Cumulant Lattice Boltzmann Method (LBM) with Multiphase Field (MPF) to simulate foam formation and investigate its thermal insulation characteristics. The cumulant LBM is employed for stable and efficient hydrodynamics simulation using parallel computers. The MPF model allows the simulation of multiple bubble interfaces in a single cell, thus preventing bubble coalescence. To study the heat transport through the foam, we focus on a scenario involving a cup of hot water cooled by cold air. Without foam, heat transport is accelerated by forced air convection and natural convection in water. However, when foam is present, it acts as a stagnant air layer. The heat is transported primarily through conduction within the foam. The foam serves as an efficient thermal insulator, impeding convective heat transfer and prolonging the retention of hot water temperature.