ABSTRACT
ABSTRACT: Numerical simulations are conducted on unidirectional flow over a submerged pipeline. Results indicated that remarkable changes of water interface profile show up over the pipeline due to the choking effects. The flow experiences a drawdown across the pipeline and the drawdown curve is asymmetry in that the rise of water level is well smaller than the drop one. The variation of water interface becomes smaller as pipeline embedment grows larger or flow depth climbs up. The variation of water interface is less than 0.5% when the pipeline is half-buried or the flow depth is large. The variation of water interface becomes much more significant when the flow velocity increases. The nadir point on the curve moves downstream with the increment of flow velocity.
