Split Thread The validity of classical physics (split from: DWFTTW)

[humber]

That's not even a sentence. You can feel the difference between laminar flow and WHAT?

If I put my hand across the belt as I stand by the treadmill, the force is felt on the side of the hand facing the usual position of the cart, and so "down" the belt. The laminar flow for an object being driven by the said "tailwind" will be opposite to that, and so "up" the belt. They are in opposition.
It is quite easy to see that the tailwind should go 'up" the belt, so you would expect that laminar flow to follow the wind, but the other belt-wind is not right at all. It is always there, belt-object or not.
Also, their relative velocities change as that object moves up the belt. This is not the equivalent of real wind, and the difference can be detected.
Equivalence says I can view both winds in this manner, but the same happens on the belt of course.

I am sure I can clear up any remaining doubts that you may have.

 

[mender]

Since you apparently like the F1 wind tunnel test, how do you think they test what the forces on the car are in a 20 mph headwind? Hint: the aerodynamic effects of the tires turning are very important on open wheel cars so that needs to be simulated accurately.

 

[CORed]

If you imagine that you are being dragged back with the belt "wind on back" then yes, you will get a laminar flow coming from behind you,

Amazing!After several weeks and hundreds of posts, it looks like he's finally getting it!

but there is also one coming towards you from the belt, dragged by the belt, towards you. This looks OK, but if you move up the belt, then you will see the relationship of the two laminar flows will change. A hand placed across the belt tells you that this is not the laminar flow of tailwind, but another spurious wind, that is also there if there is nothing on the belt to create the "pushing wind".

But no! Once again, he changes frames of reference, and thinks that it shows that the treadmill, not he, is wrong.

 

[spork]

That's a very elaborate way of saying 'you are right humber'.

I'm reasonably sure you won't find anyone in this thread saying that in an elaborate or any other manner.

girly-man (noun) -

You forgot to add "Q.E.D."

If I put my hand across the belt as I stand by the treadmill, the force is felt on the side of the hand facing the usual position of the cart, and so "down" the belt. The laminar flow for an object being driven by the said "tailwind" will be opposite to that, and so "up" the belt. They are in opposition.

If you were standing on that belt your hand would feel the same wind and the same gradient as it would if you were standing on the ground with a tailwind.

It is quite easy to see that the tailwind should go 'up" the belt, so you would expect that laminar flow to follow the wind

Yes the tailwind goes "up the belt". And no you wouldn't expect the boundary layer to go "up the belt" at the same speed or faster. You expect the boundary layer to match the speed of the surface as you approach the surface - just as it does on the road in front of your ward.

I am sure I can clear up any remaining doubts that you may have.

I have no remaining doubts about your being completely delusional. But thanks for the kind offer.

 

[humber]

Since you apparently like the F1 wind tunnel test, how do you think they test what the forces on the car are in a 20 mph headwind? Hint: the aerodynamic effects of the tires turning are very important on open wheel cars so that needs to be simulated accurately.

Well, perhaps. There are many other possibilities, the belt may not always be powered. It can be reworked for tailwinds.
That is not the point, really. The model has no meaning, as I have long been trying to tell you. The problem is general rather than specific to the cart and treadmill. No-wind simulation is not possible by this means. Powering the road cannot replace the wind.

 

[humber]

I'm reasonably sure you won't find anyone in this thread saying that in an elaborate or any other manner.

On that score, I think you are right.

If you were standing on that belt your hand would feel the same wind and the same gradient as it would if you were standing on the ground with a tailwind.

No, I have explained that.

Yes the tailwind goes "up the belt". And no you wouldn't expect the boundary layer to go "up the belt" at the same speed or faster.

A little slower relative to what? Your metaphor of the boundary layer is misconstrued. Laminar flow is part of the wind. The "slower bits" are the result of some of it, giving up some energy to the ground, over time. It's not all or nothing.

You expect the boundary layer to match the speed of the surface as you approach the surface - just as it does on the road in front of your ward.

The boundary layer "moves". It is not literally layers or a profile. It is a mass flow, the other effects are a result of that motion, but they do not drive the wind.

I have no remaining doubts about your being completely delusional. But thanks for the kind offer.

You're welcome.

 

[mender]

Well, perhaps. There are many other possibilities, the belt may not always be powered. It can be reworked for tailwinds.
That is not the point, really. The model has no meaning, as I have long been trying to tell you. The problem is general rather than specific to the cart and treadmill. No-wind simulation is not possible by this means. Powering the road cannot replace the wind.

You're evading the answer, as always when it opposes your view.

Check the latest tests by Ynot. You got some 'splainin' to do!

 

[humber]

Amazing!After several weeks and hundreds of posts, it looks like he's finally getting it!

No, you finally paid attention, CORed.

But no! Once again, he changes frames of reference, and thinks that it shows that the treadmill, not he, is wrong.

No change of "frame" required. The first tailwind laminar flow, that you clearly acknowledge comes from behind, is directly related to the belt. The other is quite clearly dragged withe the belt, and therefore also related to the belt.. Both winds have a common anchor of the belt, yet are in opposition. This state can be confirmed from the treadmill side, again with no change of "frame". If you like, we can continue until you get it.

 

[humber]

You're evading the answer, as always when it opposes your view.

Check the latest tests by Ynot. You got some 'splainin' to do!

No. I have many times stated that Ynot's system is not the same, because it has a tether. That provides a reaction arm, and that means that it may work differently but nothing about the validity.
I denied it as putative test, on that and other grounds. I can liken their errors, but it is not the same as the treadmill, because Ynot's cart can actually move. That is a critical difference.

Also, the claims of windspeed are made and based upon the current treadmill, and that too is critical
ETA:
No matter what, the claims are based upon false reasoning. That too is critical.

 

[mender]

No change of "frame" required. The first tailwind laminar flow, that you clearly acknowledge comes from behind, is directly related to the belt. The other is quite clearly dragged withe the belt, and therefore also related to the belt.. Both winds have a common anchor of the belt, yet are in opposition. This state can be confirmed from the treadmill side, again with no change of "frame". If you like, we can continue until you get it.

As usual, humber, you aren't able to make the transition properly. That's okay, some people just can't do that. I was tested for this and a few other things, spacial relations, mechanical aptitude and such as part of a possible career choice and scored very high. Others in the same room were not as successful.

So are you now saying that if it can be shown that the wind gradient is the same on the treadmill as it is outside across the ground (with suitable compensation for scaling), you might be able to get it?

 

[mender]

I denied it as putative test, on that and other grounds.

Of course you deny it, on the grounds that it proves what you are failing to understand. You should try to stay away from those grounds, they are making you look bad. Maybe if you had a look at those tests again with an open mind ...

ETA: Nah, what was I thinking! You'd have to bring a friend with an open mind with you! But that shouldn't be too hard, I imagine you have a few of those kind of friends.

Anyways, enjoy your thread. I think I'm starting to hear an echo in here.

 

[spork]

A little slower relative to what?

The surface over which it flows. Was that a rhetorical question!?

Your metaphor of the boundary layer is misconstrued. Laminar flow is part of the wind. The "slower bits" are the result of some of it, giving up some energy to the ground, over time. It's not all or nothing.

The boundary layer "moves". It is not literally layers or a profile. It is a mass flow, the other effects are a result of that motion, but they do not drive the wind.

Thanks! I must have been absent the day they covered that in my master's program in aero.

 

[humber]

Of course you deny it, on the grounds that it proves what you are failing to understand. You should try to stay away from those grounds, they are making you look bad. Maybe if you had a look at those tests again with an open mind ...

What I have just written is entirely consistent with previous claims. I have said many that it is going backwards, and the model is deeply flawed.
It's all backwards, and so forth.

ETA: Nah, what was I thinking! You'd have to bring a friend with an open mind with you! But that shouldn't be too hard, I imagine you have a few of those kind of friends.

"Open minds" often close when actually asked to do so.

Anyways, enjoy your thread. I think I'm starting to hear an echo in here.

You're welcome

 

[humber]

The surface over which it flows. Was that a rhetorical question!?

No, but certainly a rhetorical answer.

Thanks! I must have been absent the day they covered that in my master's program in aero.

Yes.

 

[CORed]

No, you finally paid attention, CORed.



No change of "frame" required. The first tailwind laminar flow, that you clearly acknowledge comes from behind, is directly related to the belt. The other is quite clearly dragged withe the belt, and therefore also related to the belt.. Both winds have a common anchor of the belt, yet are in opposition. This state can be confirmed from the treadmill side, again with no change of "frame". If you like, we can continue until you get it.

Oh, there are two winds close to the belt blowing in opposite directions.

Sorry, humber, the only person in this thread who doesn't "get it" is you. The only way I will ever "get it", if "getting it" means agreeing with you, is if I suffer some kind of massive brain damage.

 

[humber]

Oh, there are two winds close to the belt blowing in opposite directions.

"Winds" yes.

Sorry, humber, the only person in this thread who doesn't "get it" is you. The only way I will ever "get it", if "getting it" means agreeing with you, is if I suffer some kind of massive brain damage.

OK, CORed.

 

[Modified]

Why would I want to do something like that?

Crap, you finally got me. I've almost responded about four times thinking humb was humber, but that radar bit was so humberesque I didn't even bother to double check.

 

[spork]

I've almost responded about four times thinking humb was humber, but that radar bit was so humberesque I didn't even bother to double check.

Yes, but how did you like this pure humber concentrate:

When the cart he is to the area, if wheels to key have been closed, he will put himself to the back in functioning to and he will feel himself tailwind. S/he leads to front with the speed of the area, nobody will ventilate himself to feel. This is exactly analogous to the travel to the speed of wind. The consequence of the area, or the way, to the air himself and in both cases are such as he are predominated of the cart.

You'd never get humber this pure on the street, and you'd best not take it straight.

 

[humber]

Straight dope.

 

[Clive]

I have another one, Clive. 'What is the difference between a Raven and a Writing Desk?

Clive is almost an anagram of Alice, so perhaps "How are a raven and a writing desk alike?" would be more correct? Or was your error deliberate?

Anyway,the laminar flow is different in each case, Clive. It is an indicator that something is wrong. Here we go.
<snip>

I tried to follow what you wrote humber. I really did. But the further I read, the more off track you went. I have no idea what point you were trying to make with the comments about belt speed needing to follow the windspeed. What did you mean by follow? If the car is running on a belt in a tunnel in such a way that the car is always kept stationary w.r.t. the whole tunnel, then the belt speed under the car must be exactly the same value as the speed of the car over the real road for the situation we are trying to model in the tunnel.

After that you can arrange for the wind tunnel to blow air at the speed that matches the apparent wind felt by the car in the real world situation. By apparent wind, I mean the combined effect of any weather generated wind (air mass moving relative to ground) plus the effect of the car moving and thus generating its own "wind". For example, for a car driving at 100 mph over the road into a weather generated 10 mph headwind, the apparent wind felt by the car is a 110 mph headwind. If the belt and car are also on a turntable arrangement of some kind then you could simulate an apparent wind that was not necessarily an exact head or tail wind by placing the car and belt at the appropriate angle to the airflow generated by the tunnel. Note again that airflow through the tunnel needs to be at the speed of the apparent wind felt by the car in the real world situation that we are modelling. For a car(t) going downwind at exactly the speed of the wind, the apparent wind felt by the car is nil. Hence no airflow through the tunnel, and this is why spork and JB's cart on a treadmill sitting in room is just as good as a wind tunnel. The wind in the tunnel is the apparent wind felt by the car(t).

In all cases, if you get all the basic differences in velocity set up correctly, then everything else follows, laminar flow included. The only discrepancies we might expect are the mostly very minor effects from the size of the tunnel, size of the belt, and so on.