Potential flows

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Chapter 4 Potential flows

Typically, the most basic introduction on fluid dynamics usually involves the study of two-dimensional incompressible and irrotational flows, otherwise known as potential flows. There is a good reason for this: the theory is elegant, visualisable, and uses to its benefit the enormous power of complex-variable theory.

Previously, we defined the concept of vorticity via \(\omega = \nabla \times \bu\text{,}\) which serves as a measure of the local angular velocity of the flow. It turns out that in 2D, irrotational flows, with \(\omega = 0\text{,}\) provide a powerful restricton to the complexity of flows, allowing the development of the above potential flow theory..

Figure 4.0.1. From "Fundamental Principles of Flows" and "Characteristics of the Laminar and Turbulent Flows" by Hunter Rouse. Courtesy of IIHR, University of Iowa.