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There are no references on the page. I am an amauteur user but even I can see this must be addressed
I would like to add that this article is missleading. Don't use it. Examples: 1. The proper analogy is between voltage and hydraulic head - not pressure (both represent the potential energy) 2. The proper analogy is between capacitors and tanks. 3. The proper analogy is between Resistors and Pipes althogh ohm's law is not linear. 4. The proper analogy is between "Ground" and "Sea level" as reference. 3. The proper analogy is between a transistor and a valve. etc.
The main differences are: 1. There is no concept symetric to pressure in electric circuits. 2. The concept of loops is different. Water may not return to the source. 89.138.203.18 ( talk) 21:58, 13 April 2009 (UTC)
This site says: "Many writers eventually resort to some kind of water analogy to try to explain how electricity works. I have yet to see what I thought was a really good water analogy. If you want to explain electricity, talk about electricity. Hydraulics is another field entirely. Avoid this trap; it is already full."
Although I agree that most such analogies are done poorly, the potential exists for a perfectly accurate one, as they are both fluids flowing down conduits. I hope to make a page for the wikipedia that collects these ideas together into a coherent whole that the naysayers and nitpickers can then edit to perfection. - Omegatron
So I had this in my user space until it evolved into something vaguely encyclopedic, and then merged it with the pre-existing article which was just a table of related equations. Now that it is in the main article space it should evolve a lot faster. - Omegatron 02:48, July 12, 2005 (UTC)
Already I can see problems because the links are taken from websites that don't appear to be credible. If anything, they appear to be the incoherent jibberings of clueless amateurs. Take for example how pressure is equated with voltage. I'm afraid this doesn't make sense to me since pressure is what moves the liquid and so would be better equated with the electrical field since this moves charge. Secondly, unlike pressure, there is no such thing as voltage existing at a point. Voltage measures the energy gained or lost when charge moves between points and so is always referenced to two points. If you want a hydraulic analogy of voltage, then this will have to be equivalent to the energy lost or gained when a certain volume of water is transferred between two points. i.e. the change in (KE + PE). —Preceding unsigned comment added by 80.47.114.136 ( talk • contribs)
Moving some things here so that I can turn this into a real article:
I hope to make a better version of this
I have started this article independently. :-) They will be folded together when it is ready. See User:Omegatron/water analogy - Omegatron 21:42, May 24, 2005 (UTC)
Should this be renamed Hydraulic analogy to electric circuits? - Omegatron 21:42, May 24, 2005 (UTC)
I look forward to seeing this article made more complete. The heat analogy is very important historically and I think it should remain in the article and linked to Caloric theory. That being said, I think the analogy for heat is less perfect--I don't know of a thermal equivalent of a transistor, for instance, so it makes sense to me to go into more detail with the hydraulic-electric pair. -- Scentoni 06:32, 25 May 2005 (UTC)
So I attempted to merge my userfied version with the actual version, but accidentally moved the talk page over top of the article instead of the talk page, undeleted the old history before I realized it, blah blah etc. Anyway, the end result is that some of the original article's history is now in the talk page history. Sorry. All the info's still there, but it is for the wrong page. - Omegatron 02:42, July 12, 2005 (UTC)
http://virtual.cvut.cz/dynlab/courseModeling/node42.html
I've added a section about the limits of the analogy. (Useful analogies can lead to serious misconceptions when we don't know when to drop them, and instead use a better model.) — Preceding unsigned comment added by Wjbeaty ( talk • contribs) 20:12, 4 April 2006 (UTC)
although the 3d images are nice, 2d would be much clearer. —Preceding unsigned comment added by Laplacian ( talk • contribs) 02:03, 13 May 2008 (UTC)
Might it be better to describe inductance as a turbine instead, or in addition to, a paddle wheel? It seems easier to visualize a turbine as part of a closed hydraulic system as opposed to a paddle wheel, which really only works in a hydraulic analogy that includes gravity. —Preceding unsigned comment added by 128.118.147.10 ( talk) 20:26, 30 May 2008 (UTC)
So I've created this picture of a model for an inductor. It basically already fits the description in the article. Being the quantity that relates applied pressure to acceleration of the current, it can be shown that the inductance of this model equals I/(r*A)², where r is the radius of the middle of the blades to the centre of rotation, A the surface area of the blades and I the wheel's moment of inertia.-- Jocajo ( talk) 19:32, 8 February 2013 (UTC)
Has anyone ever tried to implement some logical circuitry with pipes and valves? Just for fun? A hydraulic calculator... -- dab (𒁳) 12:44, 4 September 2008 (UTC)
hydraulic analogy (derisively referred to as the drain-pipe theory by Oliver Heaviside)
hard to beleve a scientist/ mathematician would make this statement.refs rq. Wdl1961 ( talk) 15:24, 15 April 2010 (UTC)
The analogy for capacitors uses a rubber tank with a rubber diaphragm. What is the rubber lining for? Does the capacator-analogy expand as water enters it when the membrane is totally on one side?
It doesn't say that it should be filled with water even when it is "uncharged."
The "chargeness" or voltage across it is only how close the membrane is to one side. Slothman32 ( talk) 02:19, 20 April 2010 (UTC)
Only the diaphragm should be rubber. Making the sides rubber implies that the amount of charge (water) in the capacitor changes when it is charged, which is incorrect. Capacitors store pressure/voltage, not charge.
Enon continues... The correct term for this piece of plumbing is " hydraulic accumulator" or "pressure accumulator" (though the plumbing ones usually use gas and/or springs). The analogy should not use gas because charge is not similarly compressible in conductors or insulators. Also the bit about polarized capacitors and valves that was in there seems to be nonsense. Enon ( talk) 09:42, 24 December 2010 (UTC)
I have been doing a lot of thinking recently on what would be an accurate model of a capacitor in the hydraulic analogy. Although the idea of a rubber diaphragm works, I do not find it to be very elegant. I myself have come up with two models that could replace it; one similar to the current model and one based on gravity rather than some form of elasticity. Both models, by the way, are mathematically accurate, in the sense that they both correctly predict the amount of energy stored in a capacitor as a function of voltage/pressure, and also how the impedance of a capacitor in an AC circuit is affected by the frequency. I shall post images of these models with calculations within the next few days. -- Jocajo 19:44, 28 November 2011 (UTC+1)
I sometimes think of a capacitor as a cup on a balance, and when there is enough water (electricity) in the cup (capacitor), the cup tips and spills (discharges) the water. — Preceding unsigned comment added by 76.84.16.16 ( talk) 04:23, 12 April 2012 (UTC)
I hope my rubber diaphragm animation helps. To me it seems plenty a "elegant" analogue. It works on many levels--I wrote a bunch of text here. -- Steve ( talk) 20:25, 27 April 2012 (UTC)
I hereby propose an alternative to the rubber wall, namely a solid disk seperating the two terminals moved held in place by springs. I have included a picture of it here. The reason I prefer this over the rubber wall model is because it can be used to show the amount of energy stored in a capacitor, and other quantities.
This model is mathematically accurate. If we denote the pressure difference across the wall , the cross section area of the wall/tank and the stiffness of the springs combined (Hooke's law), then it can now be shown in at least two ways that the "capacitance" equals to :
What does the expression tell us? If we make the tank larger by enlarging its cross section area, we increase the capacitance. Also, the stiffer the springs, the smaller the capacitance. Is this what we expected? Yes, because it takes more pressure to push more water through, just like it takes more volts to put more coulombs through a smaller capacitor.
The model assumes the following ideal conditions:
The only problem here is that this might constitute 'Original Research', something Wikipedia is not fond of. However, this isn't research in the strict sense that it isn't a conclusion from some sort of data set, but immediately verifiable derivations.-- Jocajo ( talk) 04:06, 6 February 2013 (UTC)
It's interesting that in some situations, capacitors are analagous to pulsation dampeners (which contain some type of compressible bladder to smooth out flow fluctuations). For instance, a full wave rectifier with smoothing capacitor is a lot like a double-diaphragm pump with pulsation dampener, where the check valves are equivalent to diodes. Tara Zieminek ( talk) 20:03, 7 April 2014 (UTC)
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
Latin nonsense courtesy of the {{lorem ipsum}} template. You would instead write something like:
...this energy is , which can be rewritten as if we make the substitution from Hooke's law...
The "Hydraulic Analogy" is also the name given to the concept of using water channel flows (through a nozzle) to approximate compressible gas (such as air) channel flows. Basically, it allows you to use a "water tunnel" as a cheap wind tunnel by relating the experimental water flow results to a gas flow.
This should probably have it's own page, but I don't know if I will be able to write it. There should definitely be a link to it on this page. I'll look into it, but someone else might want to give it a try. I've never written a wiki page before.
Some references to get started: Buchanan, A., Macartney, R., Thompson, M.C., Brocher, E. & Hourigan, K. (2007) Hydraulic Analogy Study of Supersonic Rectangular-Jet Screech Control with Cylinders, AIAA Journal, 45(7), 1539–1545.
http://www.flair.monash.edu.au/publications/pdfs/BucMacThoBroHou2007_aiaaj.pdf
http://www.mubeta.monash.edu.au/publications/content/PIV09-Kumar.pdf
http://www-personal.umich.edu/~mswool/publications/quantitative_flow_visualization.pdf
Water table design for aero research using he hydraulic analogy: http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19740003970_1974003970.pdf
http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=AD0658669
Crossalchemist ( talk) 00:52, 26 August 2010 (UTC)
It's just occured to me that perhaps the reason properties of lightning are so surprising is the (subconcious or otherwise) attempt to use the hydraulic analogy for electricity - which is particularly misleading when it comes to conceptualizing how lighting travels. Wish I could find a reference for this, because it illustrates a pretty critical limiation of the hydraulic analogy. -- Wtshymanski ( talk) 21:13, 17 December 2010 (UTC)
I largely rewrote this paragraph. The possibility of "if a hole is made, the water can pour out" has nothing to do with inapplicability of Kirchhoff's current law (I guessed it was that the original author tried to explain). First of all, the analogy relies on volume (because pressure=energy/volume), not mass or other conserving quantity. An analogy to the Kirchhoff's current law should imply that the volume of the liquid is constant, even locally constant. This is possible with some clauses, but IMHO has little practical importance. First, the liquid must be incompressible. Second, the system should be enclosed in a hard envelope, such that its volume become constant. Third, this volume must be entirely filled with incompressible liquid. Then we may have the Kirchhoff's current law. And this does not mean that there are no leaks. This means that there are no exchange of substances with the outer environment, either by leaks or by moving parts such as pistons. Because this explanation is quite long, I wrote in short, why Kirchhoff's current law does not hold and removed all irrelevant reasonings. Incnis Mrsi ( talk) 18:55, 19 February 2012 (UTC)
I have the feeling that pneumatics may be a better analogy because acoustics are more pronounced. Altho the analogy is still flawed, acoustics remind me of how potential travels through electric cirquits. It is usefull for explaining stuff like reflections on signal lines and decoupling capacitors. — Preceding unsigned comment added by 83.87.238.229 ( talk) 16:03, 12 March 2013 (UTC)
After seeing all the complaints about this article, I would like to endorse it. Analogies are not only useful for understanding electricity, but also for analyzing similar systems (such as sound waves in a muffler). It is not important which analogy is used, once the reader understands that analogies are possible, it all becomes quite transparent. I like the way editors have placed alternatives in the talk page, instead of cluttering the main article with an endless list of analogies. One reason it's hard to find literature that supports analogies is that the concept is a bit "shallow" for publication. They are useful for an electrical engineer who wishes to dabble with acoustics. If this dabbling leads to anything publishable, it is easy to translate the analog equations into proper physics equations using conventional variables (e.g,, pressure instead of "pseudovoltage").-- guyvan52 ( talk) 16:20, 11 March 2014 (UTC)
Is the figure to the left a unnecessary duplicate of the one to the right?-- guyvan52 ( talk) 22:12, 12 March 2014 (UTC)
Might the opening sentence be a bit misleading? We could instead find a quote from a promoter rather than a detractor. Heaviside, Fitzgerald, Hertz and Lodge worked together on and off during 1878-1902 to flesh out JC Maxwell's work. Lodge developed many mechanical and fluid analogies of currents and fields for use in his electrical lectures. He originated most of today's hydraulic analogy, building on JC Maxwell's concept of conductors containing a charge-fluid which was incompressible. For example, see his capacitor analogy, a water-filled sphere divided by a thin rubber membrane (a balloon,) 0. Lodge "Modern views of electricity" p178 London:MacMillan 1889, described in "The Maxwellians", BJ Hunt 1991 Cornell U. Press. — Preceding unsigned comment added by 208.38.200.183 ( talk) 15:19, 21 April 2014 (UTC)
Electricity was thought to be a liquid, when was first discovered, and was described as such for years later. Perhaps it is the historical reason behind this analogy, besides the intuition, for understanding the behaviour of something invisible. The same goes for the glossery used for electricity - the word "current" (flow) comes from the analogy to water. Galzigler ( talk) 14:47, 23 September 2016 (UTC)
I have the impression this sentence is wrong: "Also, an accelerating electron will drag its neighbors along while attracting them, both because of magnetic forces."
Shouldn't it be: "Also, an accelerating electron will push its neighbors along while repelling them, both because of magnetic forces"? -- 91.34.131.163 ( talk) 18:29, 20 October 2016 (UTC)
I've have removed the original research warning template, it being 5-years-old and seems not reflective of the current article. If it is really important to you, object below. Nuvigil ( talk) 14:40, 13 June 2017 (UTC)
Please bring up to specs, see: MOS:LEAD:
"The lead serves both as an introduction to the article and as a summary of its most important aspects.
The lead should be able to stand alone as a concise overview of the article. It should define the topic, establish context, explain why the subject is interesting or notable, and summarize the most important points—including any prominent controversies. The emphasis given to material in the lead should roughly reflect its importance to the topic,"
My emphasis.
Further, the lead, in tone, seems destructive to the analogy by starting with derision and warnings. ...Is starting negatively a good way to teach a complex concept? I think somebody needs to actually try to fully
communicate this highly useful heuristic first. Also I don't think the assumption that this is "THE hydrolic analogy" can be supported. There must be hundreds.
— Preceding
unsigned comment added by
2602:306:CFCE:1EE0:E454:D78D:E92F:E1E6 (
talk)
05:19, 30 April 2019 (UTC)
I think the lede section is so far off base it needs a major re-write. See: MOS:LEAD
"The lead section (also known as the introduction, lead, or lede of a Wikipedia article is the section before the table of contents and the first heading. The lead serves both as an introduction to the article and as a summary of its most important aspects. "The lead should be able to stand alone as a concise overview of the article. It should define the topic, establish context, explain why the subject is interesting or notable, and summarize the most important points...."
It's notable as an extremely useful and unique introductory electronics teaching aid. Perhaps the main use of these analogies are to give Joe Average a basic feel for electricity, like what's the difference between voltage and current? What's current? And there is no "one" or two analogies as implied, there must be hundreds, invented on the spot by technicians every time she is asked...hundreds, all in agreement with those here. This is not the stiff rocket science this article implies. For example, take this quote: "the various electronic components are represented by hydraulic equivalents," as if the user now needs to memorize which "hydraulic equivalents" match "THE various electronic components." No. Loosen up, to: "many various electronic components can be represented by hydraulic equivalents." For example voltage, current, induction, work, resistor, some Ohm's law, can also be illustrated with just a garden faucet, hose & nozzle. These are analogies, learning aids, not rules.
And this opinion?
"As with all analogies, it demands an intuitive and competent understanding of the baseline paradigms (electronics and hydraulics)."
1.: Oh really? 2.:"paradigms?" Just what Joe Average needs, a long education in philosophy of science. Lets just hope he doesn't follow that link to get an idea what current and voltage are.
So if Joe Briefcase comes here asking; "What's current? (I have 5 - 10 minutes.)" this article is utterly counterproductive. He may as well take a class.
More technically; I also complain that here we seem to have a mere model, and a case of "misplaced concreteness," as if the analogy or model was actually a real thing. "The fallacy of misplaced concreteness...refers to the error of mistaking the abstract for the concrete." If carried to extreme, the model (since it aint the real actual thing) ends up with more patches and mental gymnastics than useful theory or model. (Economists will know EXACTLY what I'm talking about.)
I propose we treat this analogy primarily like a highly valuable (a RARE thing!) teaching tool that Wikipedia show-offs can ruin. Once that has been explained, perhaps in the lede, for the "general user," more confusing advanced electronics and detail such as our derisive Victorian Oliver Lodge, can be explained. (But seriously, what would somebody with advanced electronic knowledge be doing here?)
The article says:
The electronic–hydraulic analogy (derisively referred to as the drain-pipe theory by Oliver Lodge) [1] is the most widely used analogy for "electron fluid" in a metal conductor. Since electric current is invisible and the processes at play in electronics are often difficult to demonstrate, the various electronic components are represented by hydraulic equivalents. Electricity (as well as heat) was originally understood to be a kind of fluid, and the names of certain electric quantities (such as current) are derived from hydraulic equivalents. As with all analogies, it demands an intuitive and competent understanding of the baseline paradigms (electronics and hydraulics).
New Section: Paradigms
There is no unique paradigm for establishing this analogy. Two paradigms can be used to introduce the concept to students using pressure induced by gravity or by pumps.In the version with pressure induced by gravity,...
Rather, I propose something like this:
An electronic–hydraulic analogy (or an electricity-waterpipe metaphor) are very widely used analogies to quickly explain some basic concepts of electricity and basic electronics such as voltage, current (Amperes), resistance, and even more advanced concepts such as capacitors, inductance, and how transistors and amplifiers work. The analogy is a good one because an "electron fluid" or electric current flowing in a circuit often have strong similarities to a flowing water current in a hose or pipe. Since electric current is invisible and the processes at play in electronics are often difficult to demonstrate, the various electronic components are represented by hydraulic equivalents such as water nozzles, valves, water pumps, water towers, paddle wheels for doing work, and so forth. Indeed, electricity and heat were originally understood to be fluids, and the names of certain electric terms and concepts like current, are hydraulic.
New Section: Some Useful Specific Analogies
All working circuits (such as a flashlight or radio) have conductors, voltage, current, and resistance. By definition, a working circuit has flow. Think of water flow. Think of water pipes as the wires or conductors, pressure or pounds per square inch as voltage, think of quantity of flow such as gallons per minute as current (Amps), and a partially closed valve or friction acting as resistance (Ohms). To complete our circuit we need a source of power to pressurize and move our current. This might be pressure induced by gravity or by water pumps. In the version with pressure induced by gravity,...Now, not later we jump to relevance: how cool and elegant all this might be:]
In working electric circuits there are definite relationships among voltage, current, and resistance, such as the highly useful " Ohm's Law" formula. In working hydraulic circuits, there are similar relationships. In a garden hose, if you increase the resistance by closing the nozzle, the pressure in the hose goes up and the gallons per minute goes down. Same in our working electric circuit; if you increase the resistance (Ohms), then the voltage (volts) goes up, and the current (Amps) goes down IN EXACT PROPORTION to each other.
That's the idea. I think all of that and a little more would make a nice lede. The garden hose analogy is cool because we can get a meaty payoff without going into power source. (Slam the faucet open and shut and watch the coiled hose jump, analogy to inductive reactance, coils resisting current change.) KISS them first.
A common Wikipedia mistake is to still write for teacher who judges nice for 100% lack of error (NOT a worthy goal here) and trivial details (to prove you read the chapter,) rather than to educate curious Joe Lunchbox with a few minutes to spare, who only cares about getting an overview concept he'll find useful. I'd do it, but I'm not signed up. Feel free to copy paste.
Other than that basic easy-peasy stuff for the lede or intro for Average Joe, I'll not complain about the rest of the more formal article except to to give a definition: Definition of "equivalent" 1 : equal in force, amount, or value also : equal in area or volume but not superposable a square equivalent to a triangle 2a : like in signification or import b : having logical equivalence equivalent statements 3 : corresponding or virtually identical especially in effect or function
I think in some of its 22 usages, "similar to," "relates to," or "is analogous to," might be a more clear fit.
References
Mention what the electronic analogy of a waterfall is. Jidanni ( talk) 00:27, 1 March 2020 (UTC)
Mention what would be the hydraulic analogy of a short circuit. Jidanni ( talk) 00:45, 1 March 2020 (UTC)
Perhaps go into various lists of hydrology features, finding ones to add electrical analogies of which to this article.
Probably some don't have analogies, but probably many do. Jidanni ( talk) 06:26, 1 March 2020 (UTC)
It would be better for this article to remove the sloppy and nonsensical statement "Resistance in most electrical conductors is a linear function [maybe the anonymous author meant: "constant"?; 2012]: as current increases, voltage drop increases proportionally (Ohm's Law). Liquid resistance in pipes is not linear with volume, varying as the square of volumetric flow (see Darcy–Weisbach equation)." In contrast to what the statement suggests, the Darcy-Weisbach equation article says that the resistance is constant for laminar flow. It reduces to the Poiseuille equation. If there are no objections I would like to remove the statement within a few days. Ceinturion ( talk) 09:59, 3 April 2021 (UTC)
People come here looking for the water pipe analogy that most people are familiar with that explains current, voltage, etc. It's not here. The intro implies that it is. Derwos ( talk) 22:36, 3 February 2022 (UTC)
Obviously missing are the equations that model phenomenon. The differential equations from linear systems and the equations based on the Naperian constant 'e'.
Inductors, capacitors and filter networks common to electronic engineering circuits, especially direct current (d.c.) circuits are not presented.
The analogy with d.c. circuits is simplest and easiest to understand and use. 166.198.161.67 ( talk) 17:52, 13 January 2023 (UTC)
This my post. I'm adding a mention of banging water pipes in plumbing Jimlynnjulian ( talk) 18:13, 13 January 2023 (UTC)
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There are no references on the page. I am an amauteur user but even I can see this must be addressed
I would like to add that this article is missleading. Don't use it. Examples: 1. The proper analogy is between voltage and hydraulic head - not pressure (both represent the potential energy) 2. The proper analogy is between capacitors and tanks. 3. The proper analogy is between Resistors and Pipes althogh ohm's law is not linear. 4. The proper analogy is between "Ground" and "Sea level" as reference. 3. The proper analogy is between a transistor and a valve. etc.
The main differences are: 1. There is no concept symetric to pressure in electric circuits. 2. The concept of loops is different. Water may not return to the source. 89.138.203.18 ( talk) 21:58, 13 April 2009 (UTC)
This site says: "Many writers eventually resort to some kind of water analogy to try to explain how electricity works. I have yet to see what I thought was a really good water analogy. If you want to explain electricity, talk about electricity. Hydraulics is another field entirely. Avoid this trap; it is already full."
Although I agree that most such analogies are done poorly, the potential exists for a perfectly accurate one, as they are both fluids flowing down conduits. I hope to make a page for the wikipedia that collects these ideas together into a coherent whole that the naysayers and nitpickers can then edit to perfection. - Omegatron
So I had this in my user space until it evolved into something vaguely encyclopedic, and then merged it with the pre-existing article which was just a table of related equations. Now that it is in the main article space it should evolve a lot faster. - Omegatron 02:48, July 12, 2005 (UTC)
Already I can see problems because the links are taken from websites that don't appear to be credible. If anything, they appear to be the incoherent jibberings of clueless amateurs. Take for example how pressure is equated with voltage. I'm afraid this doesn't make sense to me since pressure is what moves the liquid and so would be better equated with the electrical field since this moves charge. Secondly, unlike pressure, there is no such thing as voltage existing at a point. Voltage measures the energy gained or lost when charge moves between points and so is always referenced to two points. If you want a hydraulic analogy of voltage, then this will have to be equivalent to the energy lost or gained when a certain volume of water is transferred between two points. i.e. the change in (KE + PE). —Preceding unsigned comment added by 80.47.114.136 ( talk • contribs)
Moving some things here so that I can turn this into a real article:
I hope to make a better version of this
I have started this article independently. :-) They will be folded together when it is ready. See User:Omegatron/water analogy - Omegatron 21:42, May 24, 2005 (UTC)
Should this be renamed Hydraulic analogy to electric circuits? - Omegatron 21:42, May 24, 2005 (UTC)
I look forward to seeing this article made more complete. The heat analogy is very important historically and I think it should remain in the article and linked to Caloric theory. That being said, I think the analogy for heat is less perfect--I don't know of a thermal equivalent of a transistor, for instance, so it makes sense to me to go into more detail with the hydraulic-electric pair. -- Scentoni 06:32, 25 May 2005 (UTC)
So I attempted to merge my userfied version with the actual version, but accidentally moved the talk page over top of the article instead of the talk page, undeleted the old history before I realized it, blah blah etc. Anyway, the end result is that some of the original article's history is now in the talk page history. Sorry. All the info's still there, but it is for the wrong page. - Omegatron 02:42, July 12, 2005 (UTC)
http://virtual.cvut.cz/dynlab/courseModeling/node42.html
I've added a section about the limits of the analogy. (Useful analogies can lead to serious misconceptions when we don't know when to drop them, and instead use a better model.) — Preceding unsigned comment added by Wjbeaty ( talk • contribs) 20:12, 4 April 2006 (UTC)
although the 3d images are nice, 2d would be much clearer. —Preceding unsigned comment added by Laplacian ( talk • contribs) 02:03, 13 May 2008 (UTC)
Might it be better to describe inductance as a turbine instead, or in addition to, a paddle wheel? It seems easier to visualize a turbine as part of a closed hydraulic system as opposed to a paddle wheel, which really only works in a hydraulic analogy that includes gravity. —Preceding unsigned comment added by 128.118.147.10 ( talk) 20:26, 30 May 2008 (UTC)
So I've created this picture of a model for an inductor. It basically already fits the description in the article. Being the quantity that relates applied pressure to acceleration of the current, it can be shown that the inductance of this model equals I/(r*A)², where r is the radius of the middle of the blades to the centre of rotation, A the surface area of the blades and I the wheel's moment of inertia.-- Jocajo ( talk) 19:32, 8 February 2013 (UTC)
Has anyone ever tried to implement some logical circuitry with pipes and valves? Just for fun? A hydraulic calculator... -- dab (𒁳) 12:44, 4 September 2008 (UTC)
hydraulic analogy (derisively referred to as the drain-pipe theory by Oliver Heaviside)
hard to beleve a scientist/ mathematician would make this statement.refs rq. Wdl1961 ( talk) 15:24, 15 April 2010 (UTC)
The analogy for capacitors uses a rubber tank with a rubber diaphragm. What is the rubber lining for? Does the capacator-analogy expand as water enters it when the membrane is totally on one side?
It doesn't say that it should be filled with water even when it is "uncharged."
The "chargeness" or voltage across it is only how close the membrane is to one side. Slothman32 ( talk) 02:19, 20 April 2010 (UTC)
Only the diaphragm should be rubber. Making the sides rubber implies that the amount of charge (water) in the capacitor changes when it is charged, which is incorrect. Capacitors store pressure/voltage, not charge.
Enon continues... The correct term for this piece of plumbing is " hydraulic accumulator" or "pressure accumulator" (though the plumbing ones usually use gas and/or springs). The analogy should not use gas because charge is not similarly compressible in conductors or insulators. Also the bit about polarized capacitors and valves that was in there seems to be nonsense. Enon ( talk) 09:42, 24 December 2010 (UTC)
I have been doing a lot of thinking recently on what would be an accurate model of a capacitor in the hydraulic analogy. Although the idea of a rubber diaphragm works, I do not find it to be very elegant. I myself have come up with two models that could replace it; one similar to the current model and one based on gravity rather than some form of elasticity. Both models, by the way, are mathematically accurate, in the sense that they both correctly predict the amount of energy stored in a capacitor as a function of voltage/pressure, and also how the impedance of a capacitor in an AC circuit is affected by the frequency. I shall post images of these models with calculations within the next few days. -- Jocajo 19:44, 28 November 2011 (UTC+1)
I sometimes think of a capacitor as a cup on a balance, and when there is enough water (electricity) in the cup (capacitor), the cup tips and spills (discharges) the water. — Preceding unsigned comment added by 76.84.16.16 ( talk) 04:23, 12 April 2012 (UTC)
I hope my rubber diaphragm animation helps. To me it seems plenty a "elegant" analogue. It works on many levels--I wrote a bunch of text here. -- Steve ( talk) 20:25, 27 April 2012 (UTC)
I hereby propose an alternative to the rubber wall, namely a solid disk seperating the two terminals moved held in place by springs. I have included a picture of it here. The reason I prefer this over the rubber wall model is because it can be used to show the amount of energy stored in a capacitor, and other quantities.
This model is mathematically accurate. If we denote the pressure difference across the wall , the cross section area of the wall/tank and the stiffness of the springs combined (Hooke's law), then it can now be shown in at least two ways that the "capacitance" equals to :
What does the expression tell us? If we make the tank larger by enlarging its cross section area, we increase the capacitance. Also, the stiffer the springs, the smaller the capacitance. Is this what we expected? Yes, because it takes more pressure to push more water through, just like it takes more volts to put more coulombs through a smaller capacitor.
The model assumes the following ideal conditions:
The only problem here is that this might constitute 'Original Research', something Wikipedia is not fond of. However, this isn't research in the strict sense that it isn't a conclusion from some sort of data set, but immediately verifiable derivations.-- Jocajo ( talk) 04:06, 6 February 2013 (UTC)
It's interesting that in some situations, capacitors are analagous to pulsation dampeners (which contain some type of compressible bladder to smooth out flow fluctuations). For instance, a full wave rectifier with smoothing capacitor is a lot like a double-diaphragm pump with pulsation dampener, where the check valves are equivalent to diodes. Tara Zieminek ( talk) 20:03, 7 April 2014 (UTC)
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Latin nonsense courtesy of the {{lorem ipsum}} template. You would instead write something like:
...this energy is , which can be rewritten as if we make the substitution from Hooke's law...
The "Hydraulic Analogy" is also the name given to the concept of using water channel flows (through a nozzle) to approximate compressible gas (such as air) channel flows. Basically, it allows you to use a "water tunnel" as a cheap wind tunnel by relating the experimental water flow results to a gas flow.
This should probably have it's own page, but I don't know if I will be able to write it. There should definitely be a link to it on this page. I'll look into it, but someone else might want to give it a try. I've never written a wiki page before.
Some references to get started: Buchanan, A., Macartney, R., Thompson, M.C., Brocher, E. & Hourigan, K. (2007) Hydraulic Analogy Study of Supersonic Rectangular-Jet Screech Control with Cylinders, AIAA Journal, 45(7), 1539–1545.
http://www.flair.monash.edu.au/publications/pdfs/BucMacThoBroHou2007_aiaaj.pdf
http://www.mubeta.monash.edu.au/publications/content/PIV09-Kumar.pdf
http://www-personal.umich.edu/~mswool/publications/quantitative_flow_visualization.pdf
Water table design for aero research using he hydraulic analogy: http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19740003970_1974003970.pdf
http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=AD0658669
Crossalchemist ( talk) 00:52, 26 August 2010 (UTC)
It's just occured to me that perhaps the reason properties of lightning are so surprising is the (subconcious or otherwise) attempt to use the hydraulic analogy for electricity - which is particularly misleading when it comes to conceptualizing how lighting travels. Wish I could find a reference for this, because it illustrates a pretty critical limiation of the hydraulic analogy. -- Wtshymanski ( talk) 21:13, 17 December 2010 (UTC)
I largely rewrote this paragraph. The possibility of "if a hole is made, the water can pour out" has nothing to do with inapplicability of Kirchhoff's current law (I guessed it was that the original author tried to explain). First of all, the analogy relies on volume (because pressure=energy/volume), not mass or other conserving quantity. An analogy to the Kirchhoff's current law should imply that the volume of the liquid is constant, even locally constant. This is possible with some clauses, but IMHO has little practical importance. First, the liquid must be incompressible. Second, the system should be enclosed in a hard envelope, such that its volume become constant. Third, this volume must be entirely filled with incompressible liquid. Then we may have the Kirchhoff's current law. And this does not mean that there are no leaks. This means that there are no exchange of substances with the outer environment, either by leaks or by moving parts such as pistons. Because this explanation is quite long, I wrote in short, why Kirchhoff's current law does not hold and removed all irrelevant reasonings. Incnis Mrsi ( talk) 18:55, 19 February 2012 (UTC)
I have the feeling that pneumatics may be a better analogy because acoustics are more pronounced. Altho the analogy is still flawed, acoustics remind me of how potential travels through electric cirquits. It is usefull for explaining stuff like reflections on signal lines and decoupling capacitors. — Preceding unsigned comment added by 83.87.238.229 ( talk) 16:03, 12 March 2013 (UTC)
After seeing all the complaints about this article, I would like to endorse it. Analogies are not only useful for understanding electricity, but also for analyzing similar systems (such as sound waves in a muffler). It is not important which analogy is used, once the reader understands that analogies are possible, it all becomes quite transparent. I like the way editors have placed alternatives in the talk page, instead of cluttering the main article with an endless list of analogies. One reason it's hard to find literature that supports analogies is that the concept is a bit "shallow" for publication. They are useful for an electrical engineer who wishes to dabble with acoustics. If this dabbling leads to anything publishable, it is easy to translate the analog equations into proper physics equations using conventional variables (e.g,, pressure instead of "pseudovoltage").-- guyvan52 ( talk) 16:20, 11 March 2014 (UTC)
Is the figure to the left a unnecessary duplicate of the one to the right?-- guyvan52 ( talk) 22:12, 12 March 2014 (UTC)
Might the opening sentence be a bit misleading? We could instead find a quote from a promoter rather than a detractor. Heaviside, Fitzgerald, Hertz and Lodge worked together on and off during 1878-1902 to flesh out JC Maxwell's work. Lodge developed many mechanical and fluid analogies of currents and fields for use in his electrical lectures. He originated most of today's hydraulic analogy, building on JC Maxwell's concept of conductors containing a charge-fluid which was incompressible. For example, see his capacitor analogy, a water-filled sphere divided by a thin rubber membrane (a balloon,) 0. Lodge "Modern views of electricity" p178 London:MacMillan 1889, described in "The Maxwellians", BJ Hunt 1991 Cornell U. Press. — Preceding unsigned comment added by 208.38.200.183 ( talk) 15:19, 21 April 2014 (UTC)
Electricity was thought to be a liquid, when was first discovered, and was described as such for years later. Perhaps it is the historical reason behind this analogy, besides the intuition, for understanding the behaviour of something invisible. The same goes for the glossery used for electricity - the word "current" (flow) comes from the analogy to water. Galzigler ( talk) 14:47, 23 September 2016 (UTC)
I have the impression this sentence is wrong: "Also, an accelerating electron will drag its neighbors along while attracting them, both because of magnetic forces."
Shouldn't it be: "Also, an accelerating electron will push its neighbors along while repelling them, both because of magnetic forces"? -- 91.34.131.163 ( talk) 18:29, 20 October 2016 (UTC)
I've have removed the original research warning template, it being 5-years-old and seems not reflective of the current article. If it is really important to you, object below. Nuvigil ( talk) 14:40, 13 June 2017 (UTC)
Please bring up to specs, see: MOS:LEAD:
"The lead serves both as an introduction to the article and as a summary of its most important aspects.
The lead should be able to stand alone as a concise overview of the article. It should define the topic, establish context, explain why the subject is interesting or notable, and summarize the most important points—including any prominent controversies. The emphasis given to material in the lead should roughly reflect its importance to the topic,"
My emphasis.
Further, the lead, in tone, seems destructive to the analogy by starting with derision and warnings. ...Is starting negatively a good way to teach a complex concept? I think somebody needs to actually try to fully
communicate this highly useful heuristic first. Also I don't think the assumption that this is "THE hydrolic analogy" can be supported. There must be hundreds.
— Preceding
unsigned comment added by
2602:306:CFCE:1EE0:E454:D78D:E92F:E1E6 (
talk)
05:19, 30 April 2019 (UTC)
I think the lede section is so far off base it needs a major re-write. See: MOS:LEAD
"The lead section (also known as the introduction, lead, or lede of a Wikipedia article is the section before the table of contents and the first heading. The lead serves both as an introduction to the article and as a summary of its most important aspects. "The lead should be able to stand alone as a concise overview of the article. It should define the topic, establish context, explain why the subject is interesting or notable, and summarize the most important points...."
It's notable as an extremely useful and unique introductory electronics teaching aid. Perhaps the main use of these analogies are to give Joe Average a basic feel for electricity, like what's the difference between voltage and current? What's current? And there is no "one" or two analogies as implied, there must be hundreds, invented on the spot by technicians every time she is asked...hundreds, all in agreement with those here. This is not the stiff rocket science this article implies. For example, take this quote: "the various electronic components are represented by hydraulic equivalents," as if the user now needs to memorize which "hydraulic equivalents" match "THE various electronic components." No. Loosen up, to: "many various electronic components can be represented by hydraulic equivalents." For example voltage, current, induction, work, resistor, some Ohm's law, can also be illustrated with just a garden faucet, hose & nozzle. These are analogies, learning aids, not rules.
And this opinion?
"As with all analogies, it demands an intuitive and competent understanding of the baseline paradigms (electronics and hydraulics)."
1.: Oh really? 2.:"paradigms?" Just what Joe Average needs, a long education in philosophy of science. Lets just hope he doesn't follow that link to get an idea what current and voltage are.
So if Joe Briefcase comes here asking; "What's current? (I have 5 - 10 minutes.)" this article is utterly counterproductive. He may as well take a class.
More technically; I also complain that here we seem to have a mere model, and a case of "misplaced concreteness," as if the analogy or model was actually a real thing. "The fallacy of misplaced concreteness...refers to the error of mistaking the abstract for the concrete." If carried to extreme, the model (since it aint the real actual thing) ends up with more patches and mental gymnastics than useful theory or model. (Economists will know EXACTLY what I'm talking about.)
I propose we treat this analogy primarily like a highly valuable (a RARE thing!) teaching tool that Wikipedia show-offs can ruin. Once that has been explained, perhaps in the lede, for the "general user," more confusing advanced electronics and detail such as our derisive Victorian Oliver Lodge, can be explained. (But seriously, what would somebody with advanced electronic knowledge be doing here?)
The article says:
The electronic–hydraulic analogy (derisively referred to as the drain-pipe theory by Oliver Lodge) [1] is the most widely used analogy for "electron fluid" in a metal conductor. Since electric current is invisible and the processes at play in electronics are often difficult to demonstrate, the various electronic components are represented by hydraulic equivalents. Electricity (as well as heat) was originally understood to be a kind of fluid, and the names of certain electric quantities (such as current) are derived from hydraulic equivalents. As with all analogies, it demands an intuitive and competent understanding of the baseline paradigms (electronics and hydraulics).
New Section: Paradigms
There is no unique paradigm for establishing this analogy. Two paradigms can be used to introduce the concept to students using pressure induced by gravity or by pumps.In the version with pressure induced by gravity,...
Rather, I propose something like this:
An electronic–hydraulic analogy (or an electricity-waterpipe metaphor) are very widely used analogies to quickly explain some basic concepts of electricity and basic electronics such as voltage, current (Amperes), resistance, and even more advanced concepts such as capacitors, inductance, and how transistors and amplifiers work. The analogy is a good one because an "electron fluid" or electric current flowing in a circuit often have strong similarities to a flowing water current in a hose or pipe. Since electric current is invisible and the processes at play in electronics are often difficult to demonstrate, the various electronic components are represented by hydraulic equivalents such as water nozzles, valves, water pumps, water towers, paddle wheels for doing work, and so forth. Indeed, electricity and heat were originally understood to be fluids, and the names of certain electric terms and concepts like current, are hydraulic.
New Section: Some Useful Specific Analogies
All working circuits (such as a flashlight or radio) have conductors, voltage, current, and resistance. By definition, a working circuit has flow. Think of water flow. Think of water pipes as the wires or conductors, pressure or pounds per square inch as voltage, think of quantity of flow such as gallons per minute as current (Amps), and a partially closed valve or friction acting as resistance (Ohms). To complete our circuit we need a source of power to pressurize and move our current. This might be pressure induced by gravity or by water pumps. In the version with pressure induced by gravity,...Now, not later we jump to relevance: how cool and elegant all this might be:]
In working electric circuits there are definite relationships among voltage, current, and resistance, such as the highly useful " Ohm's Law" formula. In working hydraulic circuits, there are similar relationships. In a garden hose, if you increase the resistance by closing the nozzle, the pressure in the hose goes up and the gallons per minute goes down. Same in our working electric circuit; if you increase the resistance (Ohms), then the voltage (volts) goes up, and the current (Amps) goes down IN EXACT PROPORTION to each other.
That's the idea. I think all of that and a little more would make a nice lede. The garden hose analogy is cool because we can get a meaty payoff without going into power source. (Slam the faucet open and shut and watch the coiled hose jump, analogy to inductive reactance, coils resisting current change.) KISS them first.
A common Wikipedia mistake is to still write for teacher who judges nice for 100% lack of error (NOT a worthy goal here) and trivial details (to prove you read the chapter,) rather than to educate curious Joe Lunchbox with a few minutes to spare, who only cares about getting an overview concept he'll find useful. I'd do it, but I'm not signed up. Feel free to copy paste.
Other than that basic easy-peasy stuff for the lede or intro for Average Joe, I'll not complain about the rest of the more formal article except to to give a definition: Definition of "equivalent" 1 : equal in force, amount, or value also : equal in area or volume but not superposable a square equivalent to a triangle 2a : like in signification or import b : having logical equivalence equivalent statements 3 : corresponding or virtually identical especially in effect or function
I think in some of its 22 usages, "similar to," "relates to," or "is analogous to," might be a more clear fit.
References
Mention what the electronic analogy of a waterfall is. Jidanni ( talk) 00:27, 1 March 2020 (UTC)
Mention what would be the hydraulic analogy of a short circuit. Jidanni ( talk) 00:45, 1 March 2020 (UTC)
Perhaps go into various lists of hydrology features, finding ones to add electrical analogies of which to this article.
Probably some don't have analogies, but probably many do. Jidanni ( talk) 06:26, 1 March 2020 (UTC)
It would be better for this article to remove the sloppy and nonsensical statement "Resistance in most electrical conductors is a linear function [maybe the anonymous author meant: "constant"?; 2012]: as current increases, voltage drop increases proportionally (Ohm's Law). Liquid resistance in pipes is not linear with volume, varying as the square of volumetric flow (see Darcy–Weisbach equation)." In contrast to what the statement suggests, the Darcy-Weisbach equation article says that the resistance is constant for laminar flow. It reduces to the Poiseuille equation. If there are no objections I would like to remove the statement within a few days. Ceinturion ( talk) 09:59, 3 April 2021 (UTC)
People come here looking for the water pipe analogy that most people are familiar with that explains current, voltage, etc. It's not here. The intro implies that it is. Derwos ( talk) 22:36, 3 February 2022 (UTC)
Obviously missing are the equations that model phenomenon. The differential equations from linear systems and the equations based on the Naperian constant 'e'.
Inductors, capacitors and filter networks common to electronic engineering circuits, especially direct current (d.c.) circuits are not presented.
The analogy with d.c. circuits is simplest and easiest to understand and use. 166.198.161.67 ( talk) 17:52, 13 January 2023 (UTC)
This my post. I'm adding a mention of banging water pipes in plumbing Jimlynnjulian ( talk) 18:13, 13 January 2023 (UTC)