Aerodynamics of Beam Wings and Crash Stuctures

[volarchico]

OK... stop and take two breaths.. Now - Get yourself educated on Newtons second law. http://en.wikipedia.org/wiki/Newton's_l ... on#Impulse

Then go and read a turbine book. Sorry.

You know what let me get you a picture.

It is an airfoil shape, and it does make lift perpendicular to the flow (not parallel). Make sure to consider the vector sum effect on the rotation of the blades and how that affects the fluid flow. Please, read a turbine book! Learn how turbines function. Lots and lots of small airfoils.

[Ciro Pabón]

I'm civil, so sometimes I use pure impulse turbines.

Look, ma! No airfoil!


Anyway, I repeat: may your words be sweet, in case you have to swallow them.

Are civil engineers more civilized? Are mechanical engineers responses, well... mechanic?

[godlameroso]

If you really want to know, Yes. I do not use those terms rigorously because it depends on your point of view.

Drag is generally what opposes the work that you trying to do, and is caused by friction if the fluid or whatever parts in the machine and the dynamics of the fluid itself. Agree?

Now..
In a turbine the fluid is doing the work... Do you call it drag or thrust? That depends. But if you check it out it's all resolved in the same direction. So when I do my turbine calculations I am not so hung up about those two words, because they don't change the resulting force on the blades. It's just me.

I do not know why you say it is irrelevant, I think it is, because there is an obvious change of direction of the fluid over the crash structure. There is only ONE result of a momentum change. IMPULSE. I had to bring up the impulse turbine to let you realise that impulse is used to generate force and especially where fluid conditions are very turbulent. The first stage of a steam turbine is usually an impulse stage. The same for a turbo charger.

You can see the impulse stage, then the reactive stage. (ignore the guide vanes)


So yeah using impulse to generate downforce is actually good especially if you are dealing with a turbulent environment. That's why Monaco spec wings are so bucket shaped. Raw downforce from momentum change.


I do not know how much downforce a curved crash structure contributes. do you?

I don't care how many degrees you have. If you checked your fluid dynamics book, I'm sure you will see what I am telling you in chapter 1 or chapter 2.

Maybe I've been wrong for the better part of nine years, but in the turbine of a turbocharger the impulse of the exhaust pulses striking the vanes is not the major contributor to it's motion. It's the difference in pressure caused by the gas expanding out of the manifold through the turbine into the downpipe. That's why for turbo applications bigger pipes after the turbine are almost always better for response and overall boost. The compressor side does the exact opposite.

Now as far as the crash structure is concerned, I've never heard of anyone using a carbon fiber banana to add downforce

I'm not sure how it interacts with the rest of the rear, but I don't see it as anything other than a turbulence generator, at least from what I can gather.

[PlatinumZealot]

That's because a car turbocharger has to operate at a high pressure gradient across a small distance.

So Yes the reactive part will play a larger role. But that part has nothing to do with the argument. I showed that picture to illustrate that the impulse stage is usually a first stage and it more immune to higher turbulence.

[PlatinumZealot]

OK... stop and take two breaths.. Now - Get yourself educated on Newtons second law. http://en.wikipedia.org/wiki/Newton's_l ... on#Impulse

Then go and read a turbine book. Sorry.

You know what let me get you a picture.

It is an airfoil shape, and it does make lift perpendicular to the flow (not parallel). Make sure to consider the vector sum effect on the rotation of the blades and how that affects the fluid flow. Please, read a turbine book! Learn how turbines function. Lots and lots of small airfoils.

I can give you a clue, there is another set of blades called the nozzles that are used to direct the stream into the buckets.



Look at the fluid exiting the nozzle, and look at the direction of rotation.

The nozzles are there to redirect and increase the velocity. I can show you a velocity diagram with all the entry angles and leaving angles if you want.

But You can still apply the principle of momentum change to F1 without the nozzles. Just remove the nozzles and rotate the image 90 degrees. Can you see this?


I mean might as well you argue with Isaac Newton. I don't think there is any more to say.

[PlatinumZealot]

We all agree that changing the direction of the flow in the right direction will create downforce. That is what you call impulse, or what I call momentum conservation.

The point I am making is that the local flow is already "bent" upwards by the beam wing and rear wing. So the crash structure is basically parallel to the local flow. So it does not change the direction of the flow, it is just shaped to go along the flow.

This is the last post I will write on this subject. If you keep omitting the main point because you just wish to talk about turbines, then that's your choice. But you should do that on a turbine forum, not an F1 one. Or at least wait until they reintroduce the turbo.

You mr Masters in some field related to fluid dynamics. You are supposed to be able to make relations between two differnt scenarios, So I do not see why I cannot bring up turbines.

I will get back to the crash structure now and top it off.

Now Let us discuss this.

[PlatinumZealot]

Crash structure has side fences on it.

[Formula None]

That's a guy wire for the diffuser, not a fence.

Now Let us discuss this.

Yes, feel free to keep making a fool of yourself.

Are civil engineers more civilized? Are mechanical engineers responses, well... mechanic?

What makes you think he's an engineer?

[PlatinumZealot]

Show ME what you got then. And Keep it on topic.

[PlatinumZealot]

I'm so appalled.

[Ciro Pabón]

What makes you think he's an engineer?

Engineer is who engineering does.

[volarchico]

I can give you a clue, there is another set of blades called the nozzles that are used to direct the stream into the buckets.
Look at the fluid exiting the nozzle, and look at the direction of rotation.

The nozzles are there to redirect and increase the velocity. I can show you a velocity diagram with all the entry angles and leaving angles if you want.

But You can still apply the principle of momentum change to F1 without the nozzles. Just remove the nozzles and rotate the image 90 degrees. Can you see this?


I mean might as well you argue with Isaac Newton. I don't think there is any more to say.

No one is arguing against Newton. Somehow you got it into your head that this is an anti-physics debate. No one says Newton or your "buckets" are wrong. What I was saying, was that turbines generally function using airfoil shapes, not buckets. Buckets can work too, thanks to Mr. Newton, no argument there. But try not to be too pompous with your responses since "buckets" aren't the only way to build a turbine.

[PlatinumZealot]

OK.. so you say there is only one beneficial effect of curving the crash structure and I said there is another beneficial effect, which you and some others think is negligible or doesn't exits at all, Correct?

[volarchico]

OK.. so you say there is only one beneficial effect of curving the crash structure and I said there is another beneficial effect, which you and some others think is negligible or doesn't exits at all, Correct?

Nope, I think you accidentally lumped me in with the others with that bold part. That's what I was trying to clarify with my last post! No one can argue against Newton. The effect of the curved crash structure is real like you mentioned. I don't know the magnitude of the effect, but it is there none-the-less.

All I meant to say: turbines use airfoil shaped blades too (not just buckets). In reality, my posts were VERY off-topic since they had nothing to do with the crash structure.

[PlatinumZealot]

turbines use airfoil shaped blades too (not just buckets). In reality, my posts were VERY off-topic since they had nothing to do with the crash structure.

I didn't say Turbines use only buckets!

And, it is your opinion that buckets blades have nothing to do with a curved crash structure.

I can see similarities but, I can't force anybody to see the similarities. So let the thread move on.