Syphoning Effect: Is It Possible?

  • Context: High School 
  • Thread starter Thread starter antekatavic
  • Start date Start date
Click For Summary

Discussion Overview

The discussion revolves around the concept of siphoning, particularly in relation to a closed reservoir containing water and a vacuum. Participants explore whether siphoning can occur under specific conditions, such as when the output is higher than the input, and the implications of pressure and gravity in these scenarios.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants assert that siphoning cannot occur if the output is higher than the input, emphasizing the role of gravity in siphoning.
  • Others propose that a vacuum created by falling water is necessary for siphoning, questioning how this applies in a closed system with a vacuum present.
  • A participant suggests that if a siphon is created and the container is made airtight, the siphon would not function due to pressure equalization.
  • There are claims that the size of the siphon may be limited, with a specific mention of a 33-foot limit for water due to atmospheric pressure constraints.
  • One participant raises a hypothetical scenario involving a bottle turned upside down and questions whether this would create a vacuum, leading to further discussion about pressure and air replacement.
  • Another participant introduces a concept of using siphoning in a geothermal context, but this is met with confusion and disagreement regarding the definition of siphoning.

Areas of Agreement / Disagreement

Participants generally disagree on the feasibility of siphoning under certain conditions, particularly regarding the height of the output relative to the input and the necessity of air pressure. The discussion remains unresolved with multiple competing views presented.

Contextual Notes

Several assumptions about pressure, gravity, and the physical properties of fluids are discussed, but no consensus is reached on the implications of these factors in the context of siphoning.

  • #31


also about steam... steam will go up if you drill a pararel pipe that is going down and conecting to the first one at the bottom.
also you can create a big presure with a syphon if the pipe goes down 1km. that is 100 times biger presure then atmosferic presure

Why would you even need a siphon? Just having a pipe from the water to the hole and down will let gravity take over. No need for a siphon at all.
 
Physics news on Phys.org
  • #32


Drakkith said:
Why would you even need a siphon? Just having a pipe from the water to the hole and down will let gravity take over. No need for a siphon at all.

My point for the last few posts - the OP is constantly on about a siphon and it's nothing to do with what they are talking about.
 
  • #33


Ido not understand you question... if you have i pipe that is going from the water to the hole then that is a siphon
 
  • #34


antekatavic said:
Ido not understand you question... if you have i pipe that is going from the water to the hole then that is a siphon

Not true in the slightest. It is simply a pipe.
 
  • #35


Drakkith said:
Why would you even need a siphon? Just having a pipe from the water to the hole and down will let gravity take over. No need for a siphon at all.

Well, I think from his previous posts, he's envisioning an over-land pipeline coming from a nearby body of water to the drilling site, but in traversing across the land, it has to go up an elevation of like 9 meters before reaching the bore hole.

It does seem to me like the pipe would act as a siphon, as long as you don't exceed that maximum height of 10m. The one limitation is that 10 meters isn't very high - but may be high enough for some sites. Wouldn't work for getting water up over a mountain.
 
  • #36


is the falling water (from the and of a pipe that is going 1km down) creating under presure?
is that underpresure the reason that you can transport water from the sea to the hole?
only the problem is that the enterence to the hole must not be 10 m above sea level
 
  • #37


antekatavic said:
is the falling water (from the and of a pipe that is going 1km down) creating under presure?
is that underpresure the reason that you can transport water from the sea to the hole?
only the problem is that the enterence to the hole must not be 10 m above sea level

You also need to factor in other things such as resistance losses within the pipe. This reduces the 10m limit further.

Not to mention the flow rate.

The system simply wouldn't be efficient enough. You'd be lucky to get it into a usable state.
 
  • #38


antekatavic said:
is the falling water (from the and of a pipe that is going 1km down) creating under presure?
is that underpresure the reason that you can transport water from the sea to the hole?
only the problem is that the enterence to the hole must not be 10 m above sea level

Could you try rephrasing that? I'm not trying to be mean, I just really have no idea what you're asking?

(I'd just like to say that I have respect for anyone trying to discuss science in a foreign language, because of all the domain-specific technical vocabulary, and because of the grammatical precision needed to clearly talk about complex topics clearly. Still, in the end, I don't understand this, so I must ask you to try again).
 
  • #39


ok i agree that it would be less then 10 meters... but i think it would be at least 9... flow rate depends on how big the pipe is or how many pipes are there... but i do not think that is an issue... you would have enough water for sure
 
  • #40


@j schmidt i just said what you said in a previus post... i was answering them not you
p.s. i do not speak english very well so sometimes...:smile:
 
  • #41


antekatavic said:
ok i agree that it would be less then 10 meters... but i think it would be at least 9... flow rate depends on how big the pipe is or how many pipes are there... but i do not think that is an issue... you would have enough water for sure

Far too many assumptions there. Recommend you run the numbers. It's worthless otherwise.
 
  • #42


@ jared i think that the factors that you are talking about work both ways
if the friction does not alow water to go up it does not alow water to go down... maybe 10 meters was a corect statement
 
  • #43


antekatavic said:
@ jared i think that the factors that you are talking about work both ways
if the friction does not alow water to go up it does not alow water to go down... maybe 10 meters was a corect statement

Friction acts to retard the flow regardless of gradient. It degrades performance.

The longer the pipe, the greater the loss.
 
  • #44


so if you conect two reservoirs 20 km apart with the same atmospheric presure the law of combined reservoirs would aplay there? would the water level be the same in two reservoirs if the atmospheric presure is the same. edit the pipe is going up end down not straight
 
  • #45


now jared will go balistic:smile:

what if you put a turbine and generator in that hole so you have hydro and geotermal energy at once:!)
 
  • #46


antekatavic said:
now jared will go balistic:smile:

what if you put a turbine and generator in that hole so you have hydro and geotermal energy at once:!)

You have to pump the water down the hole in the first place. It's a moot point.

Unless you run the numbers and check your assumptions I'm not willing to go further with this discussion. If you do so, you will see where errors are.
 
  • #47


i do not have to pump it... i can let the weight of water to do that... if the pipe narows at one point then uper pipe will acumulate water let say 200meters of water... that is a big presure
 
  • #48


Where are you pulling these numbers from? I will continue this discussion only after you show some calculations. For now, I'm out.
 
  • #49


look i am not a physicist... i am trying to make you to do calculation... i am not smart enough
and this is not a joke or understaitment
 
  • #50


antekatavic, give us a question as detailed as you can with what you want to know. We've already covered why a siphon will or will not work, so what else are you asking about? (I'm having a hard time following everything in this thread)
 
  • #51


ok. I am interested if you run a pipe from sea to a hole nearby and all the way down to magma will it start syphoning efect(after you fill the whole pipe with water)...

and if you put a parallel pipe that is going almost all the way down and then conects to a first pipe will the steam come out... or just put parallel pipe (not conecting it to a first one)?

second question is way not put some turbines and generator in the ground so you could have hydro energy from a water that is going down and geotermal from a steam going up...

also if I need to pump water under presure I can do that simply by narowing the pipe at some level and leting the water above acumulate. This pipes are going kilometers deep so i would have presure if i need it.

only problem is that the pipe which is going from the sea to a hole must never reach altitude higher than 10 meters.

I think that friction would not have afect on that number, it will afect the speed of flow but the water will sooner or later reach that elevation if nesesary..

also i think that in this way you could have more then enough water to power 1st turbine and the second with a steam.

If you are thinking that the maintenance of 1st turbine under ground is dificult you could deal that so that you put turbine in a vacuum box and above is a pipe that has more than 10 meters of water at all times and under the turbines also there is always enough water to prevent this vacuum to disappear. In vacuum turbine would not corrosion and it would revolve faster and longer because there are no air resistance.

I am having hard time to explain something in english so I am sorry if somthing you do not understand what I wrote...
edit... the pipe from the sea would probably have to go kilometers before it comes to a place where the tectonic plates colide ( that is where you can use geotermal energy)
 
Last edited:
  • #52


antekatavic said:
is it possible use syphoning efect to fill one hole (with sea water)that is going from surface all the way to magma, and drill a parallel hole to let the steam out?:smile:
If you have seawater flowing down into a hole by its own hydrostatic pressure, then being flashed to steam, it can come up through another pipe or tube because it is less dense going up than going down. This has nothing to do with siphoning. It's convection.

You could potentially even just use one tube and have a closed system that way. A lot of older home heating systems have one pipe and work the same way. Because the pipes would be long, though, a two-pipe convection system would be better.

Sorry about the capital letters in my first post: I was posting from a phone and capital letters are easier than bold.
 
  • #53


antekatavic said:
http://en.wikipedia.org/wiki/Siphon
The second problem with the chain model of the siphon is that the weight of liquid on the up side of the siphon can be greater than the liquid on the down side, yet the siphon can still function. For example, if the tube from the upper reservoir to the top of the siphon has a much larger diameter than the section of tube from the lower reservoir to the top of the siphon, the shorter upper section of the siphon may have a much larger weight of liquid in it, yet the siphon can function normally.[11]
I don't see a question anywhere in there, just a quote. Is there something you're confused about? Do you understand that it is pressure that makes a siphon work, so if the pipe size changes, the mass (weight) of the water can be larger on the high side and the siphon can still work because the pressure is still lower.
 
  • #54


antekatavic said:
what if you put a turbine and generator in that hole so you have hydro and geotermal energy at once:!)
If you siphon water from the sea over land to a pipe going down to a geothermal source, you could bury a turbine far down in the pipe and generate electricity from the falling water.

But, in so doing, you reduce the pressure of the water at the bottom of the pipe and thus reduce the pressure of the steam coming back up the pipe. There is no net gain in energy generated.
 
  • #55


I am just asking if one of you has time to run some numbers and see if this what I wrote in my previus post would work.. I do not have a knowledge to do that... all that I said in previus post is my assumption...I never did any numbers

P.S. apology accepted
 
  • #56


antekatavic said:
ok. I am interested if you run a pipe from sea to a hole nearby and all the way down to magma will it start syphoning efect(after you fill the whole pipe with water)...

and if you put a parallel pipe that is going almost all the way down and then conects to a first pipe will the steam come out... or just put parallel pipe (not conecting it to a first one)?
Yes. So far so good...
second question is way not put some turbines and generator in the ground so you could have hydro energy from a water that is going down and geotermal from a steam going up...
Won't help. See my previous post.
also if I need to pump water under presure I can do that simply by narowing the pipe at some level and leting the water above acumulate. This pipes are going kilometers deep so i would have presure if i need it.
No, you do not generate pressure by narrowing a pipe. The only relevant pressure here is hydrostatic pressure due to the weight of the column of water.
 
  • #57


antekatavic said:
I am just asking if one of you has time to run some numbers and see if this what I wrote in my previus post would work.. I do not have a knowledge to do that... all that I said in previus post is my assumption...I never did any numbers
Run numbers on what? The idea doesn't have any numbers associated with it - I'd have to generate them with scratch and I don't even really know what you're after here. I don't need calculations to evaluate the concepts here and the limiting factor in your energy output would be the energy of the heat source.
 
  • #58


the post that you do not see question is only a statement because I was trying to explain that siphon does not work because of the weight of falling water is higher then the one that is coming up.
 
  • #59


russ_watters said:
Run numbers on what? The idea doesn't have any numbers associated with it - I'd have to generate them with scratch and I don't even really know what you're after here. I don't need calculations to evaluate the concepts here and the limiting factor in your energy output would be the energy of the heat source.

Now do you see what I'm trying to say antekatavic?

You are throwing random numbers around as if they mean something. This is why I wanted you to go right back to the beginning and outline exactly what you want and then work out some some actual numbers if you want meaningful analysis / response on that aspect.

I don't know what you're going for exactly, neither does Drakkith or russ, so it's not easy to comment.
 
  • #60


antekatavic said:
I was trying to explain that siphon does not work because of the weight of falling water is higher then the one that is coming up.

EDIT: I see what your talking about.
 
Last edited:

Similar threads

Chemistry How to reverse the process of rubbing two stones in water?
  • · Replies 5 ·
Replies
5
Views
2K
Can I Siphon Water Over a 9.5m Barrier Without Pumps?
  • · Replies 8 ·
Replies
8
Views
7K
High School What Causes the Void Formation in Discarded Yogurt During Disposal?
  • · Replies 1 ·
Replies
1
Views
1K
Misc. Improving the accuracy of a grandfather clock
  • · Replies 14 ·
Replies
14
Views
724
High School Question about Thermophotovoltaics (thermal heat engine)
  • · Replies 17 ·
Replies
17
Views
2K
Can Aquaponics Help Conserve Water in Times of Drought?
  • · Replies 8 ·
Replies
8
Views
3K
The reservoir of refrigerant between condenser & metering device
  • · Replies 7 ·
Replies
7
Views
2K
High School Why does hot water rise to the top of a water heater?
  • · Replies 66 ·
3
Replies
66
Views
4K
High School Atmospheric pressure, vacuum, etc.
  • · Replies 9 ·
Replies
9
Views
2K
High School Solving Problem with Siphon: Vacation Plant Watering System
  • · Replies 2 ·
Replies
2
Views
3K