Comment on 'Lattice Boltzmann method for simulations of liquid-vapor thermal flows'

Zhang and Chen proposed a lattice Boltzmann method for simulations of liquid-vapor thermal flows [Zhang and Chen, Phys. Rev. E 67, 066711 (2003)]. In their numerical test, the authors show simulation results with a temperature ratio of approximately 1.2 for a thermal two-phase flow with $Tl0.8{T}_{c}$. However, we believe this to be erroneous and demonstrate the error to originate from a wrong choice of a parameter of critical importance in the Carnahan-Starling equation of state used in their work. Our numerical tests show that using the correct parameter choice, the scheme is only valid and robust to simulate temperature ratios below 1.10 and the lowest temperature in the flow field should be $0.85{T}_{c}$.