why does air travel faster over the top of the aerofoil than the bottom?
I know it is associated to a vigour differences though because does a air essentially transport faster? greatfully no answers containing a ‘equal movement time’ or ‘venturi nozzel’ theories.
have u observed when u dip a thin glass tube in a beaker of water what happens? water rises in the inner end of the tubes right? what force pushes the water up? its the same force that will drive the air faster. if u wanna know how that force is generated then u have to learn the ‘equal transit time’ or ‘venturi nozzel’ theories, which u dont want!!
Does it really? I remember the old argument that the air had to travel a longer distance over the top curved part of the airfoil in order to meet up with the air that had traveled along the bottom, so the air had to go faster over the top part, leading to lower pressure there and therefore lift.
Then I read arguments that said this was a fraudulent argument. The most convincing one was that planes can fly upside down. There’s clearly lift then in the ‘wrong’ direction!
Right now I am most satisfied by the simple idea that the angle of attack of the wing deflects air downward and then the wing receives an upward impulse as a result. Newton’s 3rd law makes me happy.
here’s why: the density of air IN FRONT of the wing is the same as the density at BACK. the path length over the top is, however, much longer than by the bottom, so air finding itself distributed to the top has to travel much FASTER to meet its bottom-travelling counterpart again at the back.
first of all you should know that pressure differnce is the result of this effect. so one can’t explain this effect by pressure.
ok?
we know that the density of air is constant below 1 mach. if some molecules of air hit the wings they will be sepreted. some of them will go through the upper surface of wing and some thrugh the downer. since the length of the down is less than the upper surface ( because of the curve) the upper molecules should go faster to make the velocity be constant after they quit the wing.
Related travel vacation:
- How do I travel by air when I am dependent on oxygen and prone to blood clots? I would similar to to transport by air though we do not know how to go about it when we...
- Is the air travel advisable during the last 4 months of pregnancy? What might be the negative effects? I’ve listened which after 6th month of pregnancy, the dangerous to transport by air coz of thge air vigour as...
- Is the air travel advisable during the last 4 months of pregnancy? What might be the negative effects? I’ve listened which after 6th month of pregnancy, the dangerous to transport by air coz of thge air vigour as...
- How reliable is Air Deccan for the domestic travel in India ? While on vacation India in December, you have been formulation to take Air Deccan flights in between Chennai-Delhi as well...
- Air travel is statistically fairly safe. But if something does go wrong, what is likely to be? What is a many expected to means damage or genocide in air travel? Take off, landing, automatic failure, commander error,...
If you like this blog please take a second and subscribe to my rss feedTags: nozzel, pressure differences, transit time, venturi
Comments: 5 comments
All the notebook fields that are marked with REQ must be filled when searched for
Pranay C
August 11th, 2009 at 5:09 am
have u observed when u dip a thin glass tube in a beaker of water what happens? water rises in the inner end of the tubes right? what force pushes the water up? its the same force that will drive the air faster. if u wanna know how that force is generated then u have to learn the ‘equal transit time’ or ‘venturi nozzel’ theories, which u dont want!!
Steve H
August 11th, 2009 at 5:09 am
Does it really? I remember the old argument that the air had to travel a longer distance over the top curved part of the airfoil in order to meet up with the air that had traveled along the bottom, so the air had to go faster over the top part, leading to lower pressure there and therefore lift.
Then I read arguments that said this was a fraudulent argument. The most convincing one was that planes can fly upside down. There’s clearly lift then in the ‘wrong’ direction!
Right now I am most satisfied by the simple idea that the angle of attack of the wing deflects air downward and then the wing receives an upward impulse as a result. Newton’s 3rd law makes me happy.
[I know I haven't answered your question. Sorry.]
claudius
August 11th, 2009 at 5:09 am
here’s why: the density of air IN FRONT of the wing is the same as the density at BACK. the path length over the top is, however, much longer than by the bottom, so air finding itself distributed to the top has to travel much FASTER to meet its bottom-travelling counterpart again at the back.
amir
August 11th, 2009 at 5:09 am
first of all you should know that pressure differnce is the result of this effect. so one can’t explain this effect by pressure.
ok?
we know that the density of air is constant below 1 mach. if some molecules of air hit the wings they will be sepreted. some of them will go through the upper surface of wing and some thrugh the downer. since the length of the down is less than the upper surface ( because of the curve) the upper molecules should go faster to make the velocity be constant after they quit the wing.
johnandeileen2000
August 11th, 2009 at 5:09 am
It has to cover a greater distance in the same time span than the air below the leading edge.
Leave a reply