This work is devoted to experimental and numerical studies of volt–ampere characteristics of a fixed bed heated by Joule heating. The main feature of this type of fixed bed is internal heat generation using the Joule heat. The application is to provide the heat to chemically reacting gases flowing through the bed reactor. To validate our model, a cylindrical packed bed is considered with a height of 11 cm and an internal diameter of 4.8 cm. This bed is filled with 86 balls made of carbon steel with a diameter of 1/2 in. (1.27 cm). For numerical simulation, open-source dem software is used to generate the cylindrical packed bed. Electric field distribution is calculated using a new particle-unresolved discrete element modeling-based model coupled with a discrete heat transfer model to account for the temperature dependency of the electrical conductivity of steel particles. The results of the simulation were found to be in good agreement with experimental data.