+
fuckyeahfluiddynamics:

The hummingbird has long been admired for its ability to hover in flight. The key to this behavior is the bird’s capability to produce lift on both its downstroke and its upstroke. The animation above shows a simulation of hovering hummingbird. The kinematics of the bird’s flapping—the figure-8 motion and the twist of the wings through each cycle—are based on high-speed video of actual hummingbirds. These data were then used to construct a digital model of a hummingbird, about which scientists simulated airflow. About 70% of the lift each cycle is generated by the downstroke, much of it coming from the leading-edge vortex that develops on the wing. The remainder of the lift is creating during the upstroke as the bird pulls its wings back. During this part of the cycle, the flexible hummingbird twists its wings to a very high angle of attack, which is necessary to generate and maintain a leading-edge vortex on the upstroke. The full-scale animation is here. (Image credit: J. Song et al.; via Wired; submitted by averagegrdy)
+
+
+
+
+
+
mountainhippie:

This is basically what you see on acid.
+
+
marywilliams:

Finished my Strawberry Poison-Dart Frog! Watercolor, 10” x 12”. Prints available if desired! :)
+