Irrotational and Rotational Flow

Principally speaking, a flow can be an irrotational or potential flow or a rotational flow. If the velocity vector v can be described as the gradient of a velocity potential O according to 

The difference between a potential flow and a rotational flow becomes clear by the equations 

The flow probleirrs discussed in this book can be solved by the assumption of potential flow. This irtakes the treatmeirt of fluid motion easy. 

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