Barotropic tides over rough topography generate internal tides. The non-acceleration theorem suggests that internal waves cannot exchange energy with background mean flow in the absence of nonlinearity and dissipation. Whether or how internal tides contribute mass transport still remains unclear. To clarify this problem, several numerical experiments are designed to analyze how internal tides generate residual mean flow. The effects of topography, nonlinearity and viscosity are individually investigated. The pseudo-momentum flux of internal waves is of particular concern due to its unique role in the momentum balance. Internal tides are frequently generated near the shelf break. Therefore, this study may provide a new view on the material exchange between shelves and deep sea.