Naked Science Forum
General Science => General Science => Topic started by: tommya300 on 27/07/2010 04:03:27
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Looking at the beak/bill of the Hummingbird I see a soup straw, a tweezers, a spear, a lance, a dart and an passive nose cone Aerospike cap.
The real question here is:
Does this little picker of a peck, front end apparatus, reduce air drag for this teeny, tiny, high speed blur radar blip of a bird?
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I doubt it has any significant impact on lowering drag. I can say that based on design principles utilized in aircraft.
Look at many commercial subsonic transports like the Boeing 747. Despite the fact that it can travel over 600 miles per hour, it was designed with a fairly rounded nose. To the contrary, a supersonic aircraft like the F-16 has a slender pointy nose. What drives these different design philosophies?
What needs to be said is that there is not just one kind of "drag". Two of importance are friction drag and wave drag. Friction drag is, of course, drag that is caused by friction between the air and the surface of the aircraft. The ideal way to reduce friction drag is to reduce an aircraft's surface area. The shape of minimum area is a sphere. This is why subsonic aircraft have rounded noses; to reduce surface area and therefore friction drag.
Supersonic aircraft have a type of drag that subsonic aircraft do not have to deal with: wave drag. This is caused when shockwaves form across the aircraft's surface when travelling faster than sound. The shockwaves drain the aircraft's energy, which increases drag. The best way to reduce wave drag is to make the aircraft as narrow and pointy as possible (on both ends, not just the nose!) This reduces wave drag. The increased surface area of a narrow shape will increase friction drag, but wave drag can be a much more powerful form of drag so it tends to be the focus for supersonic designs.
Looking at the hummingbird, which is VERY subsonic, I'll have to say that the beak isn't designed to reduce drag at all.
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I doubt it has any significant impact on lowering drag. I can say that based on design principles utilized in aircraft.
Look at many commercial subsonic transports like the Boeing 747. Despite the fact that it can travel over 600 miles per hour, it was designed with a fairly rounded nose. To the contrary, a supersonic aircraft like the F-16 has a slender pointy nose. What drives these different design philosophies?
What needs to be said is that there is not just one kind of "drag". Two of importance are friction drag and wave drag. Friction drag is, of course, drag that is caused by friction between the air and the surface of the aircraft. The ideal way to reduce friction drag is to reduce an aircraft's surface area. The shape of minimum area is a sphere. This is why subsonic aircraft have rounded noses; to reduce surface area and therefore friction drag.
Supersonic aircraft have a type of drag that subsonic aircraft do not have to deal with: wave drag. This is caused when shockwaves form across the aircraft's surface when travelling faster than sound. The shockwaves drain the aircraft's energy, which increases drag. The best way to reduce wave drag is to make the aircraft as narrow and pointy as possible (on both ends, not just the nose!) This reduces wave drag. The increased surface area of a narrow shape will increase friction drag, but wave drag can be a much more powerful form of drag so it tends to be the focus for supersonic designs.
Looking at the hummingbird, which is VERY subsonic, I'll have to say that the beak isn't designed to reduce drag at all.
I was not compairing supersonic to the bird's capability.
I know I am diverting from the question to supply some info to help determine some things, since you mention design.
"An aerospike is adapted to be attached to the front nose of an aerodynamically asymmetric space vehicle system, such as the external tank and orbiter of the space shuttle. The aerospike basically comprises a tapered elongated portion having a first end which is adapted to be attached to the nose of the space vehicle, and a second free end terminating in a substantially rounded disc-like tip member. Use of the spike reduces aerodynamic heating and drag during ascent of the space vehicle into its orbital position, provides an attachment point for tether operations and for propellant recovery, and permits transportion of an external tank into its orbit."
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Nah, I wasn't trying to suggest that you believed hummingbirds were supersonic.
I guess my post was just a really long way of saying that the pointy bill doesn't reduce drag.
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Nah, I wasn't trying to suggest that you believed hummingbirds were supersonic.
I guess my post was just a really long way of saying that the pointy bill doesn't reduce drag.
The reason I ask, no matter where I look to find anythink related to the Hummingbird, nothing addresses the beak being a funtioning part of the aerodinamic duct of the bird. Maybe like you informed me, if it isn't addressed it is not considered, it does not affect drag.
Thanks Supercryptid.