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.