shdw

I see why these forums are dead, good luck fellas, fly safe and study up on your dynamics.

Visit here: Does lift go up in Ground Effect? - Jetcareers if you have further questions. Competent open-minded long time members, not arrogant, close minded attitudes.

Ryan, you believe your knowledge has reached its peak, that your concepts are fact. You refuse to see that you may have misunderstood a certain aspect of what you were trying to explain.

Instead of accepting this possibility, you ignore it and argue random topics, and introducing unnecessary information to beef up your, lack of an argument regarding your fallacies. I am not saying you are all wrong!!! You are likely a brilliant person, which makes you more susceptible to these "my word is law" beliefs. But instead am saying, your ideas need work, they are far from perfect, law. Until you accept that, you will cease to learn any new information, good luck I am done here.

ryan1234

This has turned into an ad hominem argument.

'Close minded and arrogant' are attacks on the person presenting the argument.

I don't believe for one second I'm at the "peak of my knowledge" or that "my word is law" - this again is an ad hominem (which is a logical fallacy).
If you have a problem with me personally, feel free to PM me - I just don't think that a public forum is the place to call people names and psycoanalyze.

It is also bad form to effectively bad mouth someone at another forum.

Attack the argument, not the person.

We are simply talking about a phenomenon, a rather deep topic infact.

We can all be civil here, if there is something that you believe I've said in error -specifically- please feel free to point it out, and I'll do my best to defend or retract what I've said and give a reference based on a systematic opposing response/post.

Perhaps we agree to disagree.

On a more post specific note, I agree with you that there has probably been a lot of useless (and otherwise confusing) information (especially pertaining to Bernoulli) - but my point was to show that the very basic lift equation begins at F=MA - all others hold that at the core. And to answer a fellow at your other forums, yes indeed, Bernoulli's principle has become controversial lately as applied to aerodynamics (since it applies to hydrodynamics - or incompressible fluid). Bernoulli's principle is an example of the conservation of momentum though... so my (unsuccessful) purpose was to tie this to how a vortex affects each part of lift, and how the lack of a vortex affects the overall energy.

I've started to trace back through my old engineering books to better explain the relation at some point in the future.

shdw

Sir, I have repeatedly quoted and made notes on areas of error, both in this post and in the previous. You have taken those and expanded them into obscure theories to hide those errors. I don't intend on going back and recopying and re-pasting all of my own previous work in regards to this, just go reread it. Take care and good luck over here.

PS. I hope you take those previous words as insight for your future explanations, instead of personal attacks, that was their purpose.

ryan1234

You may find this other thread as interesting, though controversial, follow Cubdriver's posts - he goes through a very good description on lift. He explains things better than I could.
http://www.airlinepilotforums.com/te...on-lift-3.html

shdw

Ill make you a deal, you take a reread back through and learn what I was referring to. Mainly you are looking for things that when you say them may be taken in many ways, those are what we argued through much of this post. I will go read that article, deal?

I will read it either way, and thanks for the link.

3664shaken

Ryan,

I spent a lot of time looking into this and the confusion seems to be what Denker is saying happens in ground effect.

“When you are flying in ground effect, you are influenced by the mirror image of your bound vortex. Specifically, the flow circulating around the mirror-image bound vortex will reduce the airflow over your wing. I call this a pseudo-tailwind”

http://www.av8n.com/how/htm/airfoils.html#text61
Section 3.12.5

The only problem with this is that I can find NO corroboration of this statement in any source that I have or on the internet. The closest thing I found was another person who thought Ground Effect immediately slowed the A/C down because the IAS dropped. But that is just a build up of static pressure registering on the A/S indicator, the TAS has not changed.

If you can back up Denker’s conjecture with multiple sources then we can talk about it. Otherwise I have to stick with the a majority on this one.

Cheers.

Cubdriver

Aerodynamics is one of my favorite topics. I am Seattle this week and next, have been following these posts but I will not have time to participate until later next week. Shaken, thanks for commenting on the Denker website, and I agree you zeroed in on the key element creating confusion here. Your challenge is quite valid and I will take it up later next week, assuming no else does. And who knows, maybe we'll find it defective but it does require some time.

shdw

Just my .02 but it would seem logical that this would be the case, though I also have been unable to verify it so I ignored it through most of the discussion. Anyways, the vortices are nothing more than tornados off the back of the wing, like tornados they suck back on the aircraft (for lack of a better description) causing drag. That suction would increase airflow over the wing, without that suction it would seem logical for it to decrease. Obviously this proves nothing, but I am curious what you guys feel on that?

Cub, looking forward to hearing from it, one of my favorite topics as well.

unemployedagain

Not so much as increased lift, but reduced induced drag.

The ground partially blocks the trailing vortices and decreases the amount of downwash generated by the wing. This reduction in downwash increases the effective angle of attack of the wing so that it creates more lift and less drag than it would otherwise. This phenomenon is ground effect.

ryan1234

Denker confuses me about some things as well, a few things he says really leaves me scratching my head. I've looking into this subject in my spare time, the answer.. of course lies in circulation and basic physics as well as basic lift theory.

Aerodynamics is really a constantly evolving field of study.

One thing that has had me intrigued is wind-tunnel vs. real undisturbed air. This may sound simple, and maybe a stupid thought.... but could this change a perspective on aerodynamics. Everytime we think of airflow over a wing, we think of the air actually flowing around the wing - which isn't quite the case, rather it is a wing going through undisturbed, unforced air. What, if any, implications does this have for bound vortex and total energy?

Also, is there an overuse of the venturi to aerodynamics?