Regarding vortex forces, I have read all I can find about how vortices are used to augment lift for wings; however, I can't seem to find information on vertical vortices, and the physics of their effects on objects. How does a vortex lift an object into the air? Does the direction of the vortex matter? Will a vertical vortex below the object pull it down or support it? Does the shape of an object matter on how effectively a vortex will lift it, i.e. teardrop-shaped, convex, concave, or flat surface? Also, have there been experiments on a device creating its own vortex (other than helicopter blades), to see what kind of lift it will produce on the device? I would think these would be easy to find, but I am suprised there is so little information on this. I don't expect all of these questions to be answered, but if someone could point me to a source that could answer my naive questions, I would really appreciate it. Thank you.