To simulate Leidenfrost drops over a heated liquid pool (namely the liquid-substrate-based (LSB) Leidenfrost drops), a model of evaporation phase change contained within a three-fluid system is developed based on the ternary Cahn-Hilliard equations. In the numerical simulation, an axisymmetric model employing a hybrid LB-FD (lattice Boltzmann-finite difference) method is established, and the model and code are validated by two classical problems, i.e. lens spreading and drop evaporation. Then, the dynamics of LSB Leidenfrost droplets is unveiled numerically, and the results firstly present the distribution of evaporation flux, temperature and velocity near the LSB Leidenfrost drop. Meanwhile, this study also addresses the influence of several important parameters (including vapor Stefan number, vapor Prandtl number, drop Bond number, drop Ohnesorge number, releasing height and pool depth) on the evolution of drop volume and the configuration of quasi-equilibrium Leidenfrost system. (C) 2018 Elsevier Ltd. All rights reserved.