Prefabricated contour elements for placing on river bed - are shaped and positioned to decelerate flow and promote vertical mixing

摘要

The contoured assembly is intended for placing on the bed (5) of an open water course to decelerate the main flow (4) and/or promote mixing of the main flow with dissolved and/or suspended matter, and/or to achieve other effects associated with alterations of the flow pattern. It comprises at least one row of elements (90) arranged across (e2) the direction of flow (4) each having an upwardly inclined top surface (1) on the upstream side and a downwardly inclined surface (2) on the downstream side. The upward inclination is at an acute angle (a) to the horizontal (94) which is smaller than the acute angle (c) of the downward inclination. The angle (a) may be between 10 and 40 deg. pref. 25 deg. whilst the angle (c) is between 40 and 90 deg. pref. 65 deg.