Shaping the equation of state to improve numerical accuracy and stability of the pseudopotential lattice Boltzmann method

Author(s)

Czelusniak, Luiz Eduardo ; Mapelli, Vinicius Pessoa ; Wagner, Alexander J. ; Cabezas-Gomez, Luben

• Document type: Journal article
• Source: PHYSICAL REVIEW E; v. 105, n. 1, p. 15-pg., 2022-01-10.

Abstract

It has recently been shown that altering the shape of the metastable and unstable branches of an equation of state (EOS) can substantially improve the numerical accuracy of liquid and vapor densities in the pseudopotential lattice Boltzmann method [Peng et al., Phys. Rev. E 101, 063309 (2020)]. We found that this approach reduces stability of the method in nonequilibrium conditions and is unstable for bubbles at low reduced temperatures. Here we present an improved method for altering the shape of the metastable and unstable branches of the EOS which remains stable for both equilibrium and nonequilibrium situations and has no issues with bubbles. We also performed a detailed study of the stability of the methods for a droplet impact on a liquid film for reduced temperatures down to 0.35 with Reynolds number of 300. Our approach remained stable for a density ratio of up to 3.38 x 10(4). (AU)

• FAPESP's process: 18/09041-5 - Study of Lattice Boltzmann Method for modeling flows in microchannels of solar absorbers
• Grantee: Luiz Eduardo Czelusniak
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 16/09509-1 - Phase change heat transfer processes of high performance applied to solar energy recovery
• Grantee: Gherhardt Ribatski
• Support Opportunities: Research Projects - Thematic Grants