Nappe (water)

The term Nappe when used in relation to hydroengineering refers to the sheet of water over-topping a dam. It is an important issue in dam construction because unless air can be introduced into the nappe, the vibration of the water can lead to dam failure.

Nappe vibration can be managed by flow splitters in the dam wall design.

Nappe- The underside of which is not in contact with the overflow of structure and is at ambient atmospheric pressure.

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