▎ 摘　　要

Phonon hydrodynamics originated from the Guyer-Krumhansl heat conduction model. However, there is still no reasonable explanation for the high thermal conductivity of suspended graphene by using the Guyer-Krumhansl heat conduction model. In this article, based on the Guyer-Krumhansl equation we find that the inflow boundary condition specifying the non-zero heat flux at the inlet of the rectangular twodimensional nonmetallic materials can induce phonon transport. Results show that the combined action of the phonon flow caused by the inflow boundary condition and the Poiseuille phonon flow induced by the temperature difference can make the effective thermal conductivity of two-dimensional nonmetallic materials (such as suspended graphene) much higher than the bulk thermal conductivity. (c) 2022 Elsevier B.V. All rights reserved.