Two-dimensional gas heat conduction under zero average temperature difference

Abstract This study investigates heat conduction in a two-dimensional gas system under dynamic nonequilibrium thermal driving. The two-dimensional gas system evolves via multiparticle collision dynamics, where the temperature of the left heat bath oscillates periodically over time, while the right heat bath remains at a fixed temperature. It was discovered that, even when the effective average temperature difference approaches zero in the high-frequency limit, the system can still generate a net heat flux. This phenomenon is attributed to the joint influence of the time-varying temperature and interparticle interactions. Here, the interaction strength is modulated by the discrete time step, with smaller time steps corresponding to stronger interactions. The heat flux reaches a maximum at an optimal interaction strength, and this optimal value exhibits a linear relationship with the system length. These findings offer new perspectives for thermal management in micro- and nanoscale fluid systems.