Phase portraits for sinks can often like eddies in water, so I would assume there is some fluid or aerodynamic system where these curves appear. But, the only difference between a saddle and a nodal source/sink is that one eigenvalue is positive, so theoretically there could be a situation where with one eigenvalue fixed, the other changes from something like -0.01 to +0.01. Are there any dynamic systems that have completely changing types of flows like that in real-time?
4
-
$\begingroup$ Suppose you have a bathroom sink. Water flows to the center and down the drain. Suppose the sink is 0.01 m deep. Now change the curvature in the x direction, but leave the y direction fixed. Make x flat, and then curved upward 0.01 m. $\endgroup$– mmesser314Commented Apr 10, 2019 at 5:37
-
$\begingroup$ Perhaps you are looking for incompressible extensional flow whose strain rate tensor has at least one positive and at least one negative eigenvalue (corresponding to stretching and compression respectively) so as to satisfy continuity. $\endgroup$– DeepCommented Apr 10, 2019 at 9:59
-
$\begingroup$ Page wouldn't load though. $\endgroup$– Vane VoeCommented Apr 10, 2019 at 15:29
-
$\begingroup$ It is loading correctly in my chrome browser. Here's the link: sharcnet.ca/Software/Ansys/16.2.3/en-us/help/poly_pm/… $\endgroup$– DeepCommented Apr 11, 2019 at 5:24
Add a comment
|