# Thread: More Returns Than Actually Needed ???

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## Prop,

that statement makes no sense! Lets paint by the number here;

Lets say we have a plane in flight, two molecules of air hit the front of the wing. One molecule goes over the top of the wing while the other goes underneath the wing.
The speed inwhich the two molecules travel have been predetermined by the engine and propeller. At this given speed are you saying that the two molecules reach the rear of the wing at the same time simply by having the molecule over the top of the wing go faster?

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## Topic

Don’t loose focus we are talking about the importance of return air? Not fully understanding is not a reflection on mechanical ability. This is more of a design factor but a very important one. That is if you want the system to work efficiently and with as little undue stress as possible.I like this site because I learn.

Static pressure, fan blade shape, duct shape and size, turning veins, all have an impact on the system. Bernoulli’s law is in important part of understanding.

It would be like working on a steam boiler but not knowing how steam is made or what temperature is used.

What do you think? Does high pressure steam move faster or slower then low pressure steam and why or why not.

3. ## Re: Prop,

Originally posted by air2spare
that statement makes no sense! Lets paint by the number here;

Lets say we have a plane in flight, two molecules of air hit the front of the wing. One molecule goes over the top of the wing while the other goes underneath the wing.
The speed inwhich the two molecules travel have been predetermined by the engine and propeller. At this given speed are you saying that the two molecules reach the rear of the wing at the same time simply by having the molecule over the top of the wing go faster?
The speed of the wing is constant, the path under the wing is shorter than the path over the wing. Time is the same.

Longer distance in same time is faster.

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## this is a dead end

and my point is this, the lift on the wing is achieved by moving more air under the wing than over the wing. There is no negative pressure over the air foil, just less. Planes are pushed up not sucked up.

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## Re: Topic

What do you think? Does high pressure steam move faster or slower then low pressure steam and why or why not.
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Do you have a particular scenario in mind? This is quite vague

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## We have beaten this thing to the end

To generate lift on the wing the wing must be tilted with respect to air flow, so the flow travels farther across the top then under the bottom. This tilting is called the angle of attack. Downward airflow deflection occurs when air flows over the upper wing surface.

Since for every action there is an equal but opposite reaction the opposite action of the downward deflection is push upward (lift)

We need somthing new next week

7. It you have a 100 foot tall, 30 foot wide silo, how high can you fill it with cornflake cereal before the cornflakes on the bottom are crushed.

Thats for next week.

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Originally posted by beenthere
It you have a 100 foot tall, 30 foot wide silo, how high can you fill it with cornflake cereal before the cornflakes on the bottom are crushed.

Thats for next week.
The corn flakes at the bottom are always crushed in the boxes I get.

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## Heres one for next week

If a tree falls in the forrest but there are no humans or animals close enough to hear it, does it make a noise? I have a theory

10. all i know is when all you guys are 40,000 ft up hoping the wing was put on correctly and dont fall off
i will be on the ground thinking what a f%%%%%%%% recall that one is heheheheheeheh
flying is for the birds

11. All I know is that whatever is going on with my square parachute that keeps me from smashing into earth, it doesn't "suck"!

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## Re: Prop,

are you saying that the two molecules reach the rear of the wing at the same time simply by having the molecule over the top of the wing go faster?
Counterintuitive, isn't it? Maybe part of why flight didn't get invented earlier.

Here's a fun trick. You need two things: 1. kitchen faucet. 1. soup spoon.

Open the faucet to make a nice smooth stream of clear water running down (not so fast it gets all full of bubbles from the aerator).

Hold the end of the spoon handle lightly between your fingertips so the spoon end hangs very loosely straight down.

Move the spoon slowly over until the bottom of the spoon's bowl end - the convex side - just barely touches the water stream.

I'll look forward to watching the arguments over what happened.

The old ping-pong-ball-over-a-hair-dryer is fun too. Dryer set on cool.

----
Ping the pong ball of my heart, dear. -Albert T. Alligator

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## yup

The spoon pulled right in could you explain why.

How would this have an effect on a supply loop and return? Does the distance, placement of tee location change the flow?

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