Do floating objects clump together on curves in rivers?

In summary, the Casimir effect is a phenomenon where objects tend to clump together on curves due to the decreased water velocity. The Bernoulli effect is when objects are attracted to each other due to the faster flow. The Casimir effect is related to the wave energy that is reflected from the boats.
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zuz
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I recall reading somewhere about when anything, (eg. cars on the road, balls in a flowing stream) tend to clump together on curves. I don't remember where I read it but I seem to think there was some principal involved. Has anyone ever heard of this before, or am I mistaken. Thanks.
 
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I'll take an amateur stab at this (I probably shouldn't, but I have no willpower):
A river often digs into the bank at a curve and leaves a stagnation point where the water just swirls around. Anything washed into it will tend to stay there and get tangled up with other things. And the decreased water velocity let's stuff settle there.

EDIT: The following posts seem to indicate that I got it wrong. On a curve, the outside of the curve has higher velocity water which caries away dirt and debris and the inside of the curve has slower velocity water where dirt and debris are deposited.
 
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You can read up on it yourself for meandering rivers.
An example hit
http://www.seddepseq.co.uk/DEPOSITIONAL_ENV/Fluvial/Meander/meander.htm
meandering rivers typically only contain one channel that winds its way across the floodplain. As it flows, it deposits sediment on banks that lie on the insides of curves (point bar deposits), and erode the banks on the outside of curves
 
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zuz said:
I recall reading somewhere about when anything, (eg. cars on the road, balls in a flowing stream) tend to clump together on curves. I don't remember where I read it but I seem to think there was some principal involved. Has anyone ever heard of this before, or am I mistaken. Thanks.
@FactChecker and 256bits have given details and I am not educated in this so @daven could give insight on this.
This is cool and gives examples across the world.
 
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It is clear that if objects cannot pass, then they will tend to bunch up with fast ones at the rear and slow ones in the lead. Car drivers reaching a curve slow down, overcautious drivers slow down more, so tend to obstruct the others, which results in natural bunching.
If cars enter a road section two seconds apart, and remain 2 seconds apart, then they will be closer where the speed is lower, such as at corners. Because cars do not have zero length, the linear separation is reduced quickly and could cause a pileup when it takes a vehicle more than two seconds to travel it's own length.

Where flowing water forms an eddy, that is drained by a central downward movement, any floating objects that enter the eddy will collect there, unless they sink in the whirlpool.

A hydrophobic floating object, such as a waxed wooden block floating on water, will form a local depression in the surface. Two such objects will move together as they slide down the slope of the water surface. Indeed, one hydrophobic object will attract any other floating object.

Ships close together, becalmed at sea are drawn to each other because one will shelter the other from light variable winds. Maybe that is an analogue of the Casimir effect.
If there is a swell then some wave energy will be reflected from the boats. That should also push them together. I believe the presence of the oscillatory swell makes that the Casimir effect.
Where wind blows through the gap between two close vessels, the wind speed is slightly greater than outside the vessels. Faster flow implies lower pressure between the vessels, so they should be attracted together. That is the Bernoulli effect. It requires the wind be sufficient to flow around and between the boats, while not strong enough for the boats to sail apart.
 
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Actually I mentioned this on another site and someone mentioned density waves and I think that is what I had heard earlier. Thanks everyone.
 

Related to Do floating objects clump together on curves in rivers?

1. Do floating objects clump together on curves in rivers?

Yes, floating objects have a tendency to clump together on curves in rivers due to the change in flow direction and speed. This phenomenon is known as "river convergence" and is caused by the centrifugal force acting on the objects as they move around the curve.

2. Why do floating objects clump together on curves in rivers?

As mentioned before, the change in flow direction and speed on curves in rivers creates a force that pulls the objects towards each other. This force is stronger on the outside of the curve, causing the objects to clump together on that side.

3. What types of floating objects tend to clump together on curves in rivers?

Any type of floating object, such as logs, leaves, or debris, can clump together on curves in rivers. However, larger and more buoyant objects are more likely to be affected by river convergence.

4. Can the clumping of floating objects on curves in rivers be dangerous?

In some cases, yes. If there is a large amount of debris or floating objects clumped together on a curve, it can create a blockage in the river and cause flooding or damage to structures downstream. It can also be hazardous for boaters or swimmers, as the objects may be difficult to navigate around.

5. Is there any way to prevent or minimize the clumping of floating objects on curves in rivers?

One way to prevent or minimize the clumping of floating objects on curves in rivers is by implementing river management strategies, such as installing barriers or redirecting the flow of the river. Regular maintenance and clean-up of debris can also help reduce the likelihood of clumping on curves.

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