A three-dimensional transient double-population thermal lattice Boltzmann BGK scheme for the global evaporator of a CPL is proposed to describe the heat and mass transfer in the porous wick, the cover plate and the vapor groove. The lattice BGK D3Q6 model, developed on passive-scalar approach, is proposed to represent the energy distribution function. The D3G15 incompressible lattice BGK model is chosen to represent the pressure distribution function to calculate the pressure and velocity fields. The random porous structure is reconstructed by the quartet structure generation set (QSGS) and is coupled to the lattice Boltzmann method (LBM) by some special boundary schemes for pore scale simulation. The numerical results of different working conditions and different working fluids are presented, which can improve the understandings of heat and mass transport mechanisms in a CPL evaporator and provide guidance for the evaporator design in a CPL system. (C) 2011 Elsevier Ltd. All rights reserved.