The pore-scale numerical simulation of fluid flow and heat transfer processes in the random structures are given. By comparing the simulation results with the corresponding experimental data, the validity of the structure model and the heat transfer model are verified. The macro analysis is given, it is found that the mean porosity, various flow scalars and heat transfer scalars in the packed structures are all periodically distributed, and the influence of inlet velocities, spheres size and other parameters on the turbulence and temperature field in porous media is described in detail. The large eddy simulation (LES) method is used to study the flow and temperature field under pore-scale in the local porous structure, the distribution characteristic of eddies in porous structure was obtained, and the change regulation of isothermal surface shape (fractal dimension of surface) with heating is also given. (C) 2020 Elsevier B.V. All rights reserved.