When G is -0.5, 0, 0.5 and 1, the pipe is exposed on the bed surface. After scouring, the depth of the scouring pit at the bottom of the pipeline is 2.8cm, 2.4cm, 1.6cm, 0.6cm in sequence.
When G is -0.5, 0, 0.5 and 1 respectively, the pipe is exposed to the bed. The depth of the pipe bottom flushing pits after flushing is 2.8cm, 2.4cm, 1.6cm and 0.6cm.
When G is - 0.5, 0, 0.5 and 1, the pipeline is exposed to the bed surface. The depth of scour pit at the bottom of the pipeline is 2.8cm, 2.4cm, 1.6cm and 0.6cm respectively.<br>