A velocity field (or 2D flow field) describes fluid flow using a vector field under the continuum assumption. Fluid flow is modeled in the and directions. Streamlines are plotted for the velocity field generated by the components of the velocity vector; a streamline is tangent to the velocity field everywhere. Use the sliders to vary the values of the coefficients, exponents and constants of each component and of the velocity vector. Set the axes range with a slider and use the check boxes to select whether positive, negative or both axes ranges are displayed.

The velocity vector for a flow field defines fluid velocity in the , and directions is:

,

where , and are the , and components of the velocity vector, and , and indicate the direction of the vector component. For this Demonstration, flow is only in the and directions, so simplifies to:

.

In this Demonstration, the components of the velocity vector are defined as:

,

.

Reference

[1] B. R. Munson, T. H. Okiishi and W. W. Huebsch, Fundamentals of Fluid Mechanics, 6th ed., Hoboken: John Wiley & Sons, 2009.