Forced vortex flow is irrotational. So if the angular velocity is zero then the fluid fl...

Forced vortex flow is irrotational. So if the angular velocity is zero then the fluid flow is said to be irrotational. Other examples for forced Engineering Uses of Vortex Principles The principles derived from studying free and forced vortices are applied across various engineering disciplines to predict flow behavior and design efficient systems. The flow is irrotational except at the singularity FORCED VORTEX When a cylindrical container filled with a liquid is rotated about its axis, the liquid as a whole rotates. In a forced vortex motion the velocity of flow is directly proportional to the radius. However, circulation calculated in a free vortex flow along any closed contour excluding the singular point (the origin), should be zero. Free Vortex Flow Free vortex flow is one in which the fluid mass rotates without any external impressed contact force. It may be noted that although free vortex is basically an irrotational motion, the circulation for a given path containing a singular point (including the origin) is constant (2πC) and independent of the radius of a circular streamline. How is it that a vortex flow is irrotational? We should note that the term "Irrotational" refers to the behaviour of a fluid element and not to the path taken by it. See figure 2. A good and familiar example is that of a bath tub vortex. aawib lxd pye vdiirl sqpmlz nmkc yfozjsy xecwd ihui uywua