The effects of entrance geometry on coefficient of discharge in culverts

Culvert is a device, which is used for the flow passage under embankment, railroad, canal and…It has a simple structural design, but a complex hydraulic condition, so applying it needs a great sensitivity. If it has a clear characteristics, its sensitivity will be reduced .To have an economical area for passing a fixed flow we should reduce losses as possible. This research deals with three kinds of culvert entrance (curved up edge–curved side edges-sharp edges). First, the result of sharp edge model is compared with Bodhaine, s and this model is taken as the base after being sure of its results. The curved up edge model is effective so there is not any increase in coefficient of discharge. Therefore, there was not increase in coefficient of discharge. In addition, bottom slope, culvert length and the discharge do not have any effect on coefficient of discharge for flow types1, 2, and 3.

کلیدواژه ها:

culvert ، coefficient of discharge ، entrance geometry