Talk:Turbocharger

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General clarity

This page lakes a crystal clear explanation that take the reader from not understanding what a turbo does and how, to understanding. I don't know what a turbo does and how it works, I've read the page, I still don't understand. A good diagram wouldn't go amiss. — Preceding unsigned comment added by 124.181.17.243 (talk) 07:59, 17 March 2012 (UTC)

Totally agree, the intro is way too scientific, needs a broad intro in layman's terms. I'll have a crack, feel free to modify. <edits page> Ok, a few notes

• what does "Turbochargers have also been found useful compounding external combustion engines " mean? Needs a rewrite for clarity
• paragraph about rail EMD engines is too specific for intro. Moved to "marine and land-based" section (could use some finessing over there. I suggest rail turbo engines deserve their own section, but I don't know enough about the topic, so I won't mess with it!1292simon (talk) 02:05, 22 March 2012 (UTC)

turbine section is a heat engine? What?

"The turbine section of a turbocharger is a heat engine in itself. It converts the heat energy from the exhaust to power..." "Because a turbocharger is a heat engine, and is converting otherwise wasted exhaust heat to power..."

That doesn't make any sense at all. It doesn't use the heat energy of the exhaust to do anything, it's driven by the exhaust gases flowing through. The movement of the gases is the important factor, not their temperature. —Preceding unsigned comment added by 91.16.88.217 (talk) 18:46, 5 March 2009 (UTC)

The temperature does matter. As the exhaust gases flow in to the turbo, they pass through a restriction, in essence a venturi (in a gas turbine engine we call it the turbine nozzle diaphragm). According to Bernoulli's Principle and the law of continuity, the velocity of the gases increases while their pressure and temperature decrease. Yes, it is primarily the velocity of the gases which acts on the turbine rotor in order to transfer energy, but the extra velocity is created by converting heat to velocity. After the gases have spent some of their velocity by imparting force to the turbine, their pressure and temperature increase again, but the temperature never rises as high as it was in the pre-turbo section of the exhaust. So, the statement that a turbo is a heat engine is technically true, although in the context it may be distracting especially since it's mentioned twice. Shreditor (talk) 09:51, 6 March 2009 (UTC)

This is misleading, a heat engines purpose is to convert heat into kinetic energy. This is not the turbochargers purpose, and the heat engine aspect provides little impact on the turbochargers performance. —Preceding unsigned comment added by 90.196.17.88 (talk) 23:12, 24 May 2009 (UTC)

I think you are mistaken. A heat engine converts heat energy to mechanical power, which exactly what the turbine in a turbocharger does. I've explained how it works above, and the article explains it as well. Shreditor (talk) 02:30, 25 May 2009 (UTC)

as far as I can figure, there would probably be no benefit if it wasn't using the heat of the expanding/cooling gas thru the turbine.. otherwise everything would just use mechanical superchargers. i'm pretty sure expanding/cooling gas is how you get a net thrust thru a jet engine.. (i have tried in my mind to argue both sides before posting this -- but i'm drunk) maybe carnot_cycle is it --98.246.94.67 (talk) 07:46, 9 June 2009 (UTC)

If one removed the heat of the exhaust through a heat exchanger in the path of the exhaust pipe and just used the flow of air/gas through the compressor it would operate the same and still produce boost because of it's flow through the turbo's fan blades. The venturi effect of a turbo? A venturi purposely put into a pipe is to lower the air pressure at a specific point in the tubing. The “Venturi effect“ can also separate heat and cold from the air coming through the piping if designed correctly. You may want to consider they also reduce the size of the intake into the turbo for another reason, to increase the speed of the flow through the restriction. —Preceding unsigned comment added by Badmoonryzn (talk • contribs) 10:52, 17 June 2009 (UTC)

There is no question that a turbocharger's turbine section is a heat engine. The hot exhaust gases impinge on the carefully shaped blades of the turbine, and the gas molecules transfer much of their momentum to the blades as force, The blades are attached to the shaft, thereby producing torque at very high speed. The resulting power drives the compressor. In the process, the temperature of the exhaust gas drops several hundred degrees. The process here is the same as a gas turbine jet engine, just at a lower temperature.

A turbocharger for a particular large diesel engine (over 2,000 horsepower) will individually produce 300 hp from its own turbine to drive its compressor section. There are four of those turbochargers per engine. If they were only getting the power from differential pressure in the exhaust manifold to atmosphere, then it would be extracting that power from the engine itself. The loss of power due to back pressure of the turbos is far, far less than the power being produced by the turbos themselves. Hence they ARE heat engines. If you are still not convinced, read the article on turbocompounding elsewhere in Wikipedia. But please stop writing that it is only the differential pressure where the power comes from, because that is inaccurate and gives this topic area a bad name. Tquinn2 (talk) 16:14, 20 August 2009 (UTC)

Take any turbocharger. Put it on a test bench. Heat or cool the air on any of the inlets and outlets any way you choose (temperature only -- no fair adding a pressure differential). See if it starts spinning. Heck, go ahead and spin it up using an external motor, disconnect the motor, and watch as it slows down and comes to a stop. Now try the same experiment with a stirling engine, which is a heat engine. Now get rid of the heat differences, make the temperature on all of the inlets and outlets exactly the same, but with a pressure differential. Now see if it spins.

The heat energy in the exhaust IS used, it is not just the velocity of the gas but also the heat contained within the gas stream, The temperature and pressure of the gas reduces as the gas expands across the turbine, the higher the temperature the more it expands for a given pressure and the more energy it gives up to the turbine. Its basic turbine physics and its the same in a steam turbine used in almost every power station (or else why would we burn so much fuel heating it up !). As such, heat in the exhaust flow IS used to produce mechanical work and is therefore a heat engine — Preceding unsigned comment added by 192.149.117.67 (talk) 06:50, 11 December 2018 (UTC)

(The entire system -- the internal combustion engine with the turbocharger attached-- is a heat engine. It converts the heat from the burning fuel to mechanical energy. But the turbocharger alone in no more a heat engine than the crankshaft alone is._ --Guy Macon (talk) 15:23, 19 November 2018 (UTC)

Sorry Guy, your wrong. Heat energy is consumed by the turbine as well as energy in the gas flow. Its part of the reason for wrapping headers, this reduces the loss of heat in the gas before it enters the turbo and gives a small increase in the efficiency. — Preceding unsigned comment added by 192.149.117.67 (talk) 04:50, 20 December 2018 (UTC)

Tags & templates

Typ932. Please do not remove valid tags and templates. You're certainly correct that the whole article needs better references, and more of them. That necessity, however, does not preclude the use of templates in specific sections to focus editors' attention on an article's particular needs. Also, it is not okeh to remove tags simply because you consider the assertion to be common knowledge; the standard for inclusion of information on Wikipedia is not what we know (or what we think we know, or what we think everybody knows). It is what we can prove. If the assertion in question is as commonly known to be true as you say, then it should be very easy to document reliably. Thanks. —Scheinwerfermann ^T·_C20:47, 1 April 2009 (UTC)

Typ932, I need to ask you again to please stop removing valid tags and templates without addressing the needs they indicate, for it's neither helpful nor productive. I've moved the Article issues template to the top of the article, because as you have observed, the whole article needs improvements. Please keep in mind that Wikipedia is a coöperative effort, not a combative one; we make edits to improve the project, not to express our opinions of other editors. Everybody's productive contributions are welcome; might you look into finding and supplying good refs for the tagged assertions? Thanks! —Scheinwerfermann ^T·_C16:05, 2 April 2009 (UTC)

Turbos are superchargers driven by heat

The first section is contradicted by the second section. The second is correct. The fist should be changed.

A turbo charger is not "like a supercharger", it is a type of supercharger. Supercharging is pressurizing a manifold. It is a turbine driven supercharger.

Well, technically you are correct. In the context of engines, however, turbochargers are always exhaust-driven, and superchargers are always belt driven. They do the same job, but one is a turbomachine and the other is not. Perceptually, they are two totally different machines that serve the same purpose (pressurizing the intake manifold). I think we should be mindful of this fact and realize that common usage and the proper scientific nomenclature conflict. Msaunier (talk) 15:19, 19 July 2011 (UTC)

And the turbine is driven by heat. Have a free link. More heat gives you more pressure. The greater the differential, the faster the "flow" of pulses, as the gas expands from cooling.

Heat is incidental to a turbocharger. While a turbine engine is driven by heat (expanding exhaust gases), a turbocharger is driven by pressure. Exhaust gas is being forced out of the engine by the pistons during the exhaust stroke, and is forced through the turbo input vanes. While it is true that the exhaust gases are quite hot at this point and that their expansion inside the turbocharger gives greater output and is desirable, a turbo is burning no fuel and ultimately is powered by the differential pressure between the exhaust stream and the outside atmosphere. Even if the exhaust coming in to the turbo was somehow cooled to the temperature as ambient, the turbo would still perform useful work. Msaunier (talk) 15:19, 19 July 2011 (UTC)

http://www.turbobygarrett.com/turbobygarrett/tech_center/turbo_tech101.htmlools)

"The temperature does matter. As the exhaust gases flow in to the turbo, they pass through a restriction, in essence a venturi (in a gas turbine engine we call it the turbine nozzle diaphragm). According to Bernoulli's Principle and the law of continuity, the velocity of the gases increases while their pressure and temperature decrease. Yes, it is primarily the velocity of the gases which acts on the turbine rotor in order to transfer energy, but the extra velocity is created by converting heat to velocity. After the gases have spent some of their velocity by imparting force to the turbine, their pressure and temperature increase again, but the temperature never rises as high as it was in the pre-turbo section of the exhaust. So, the statement that a turbo is a heat engine is technically true, although in the context it may be distracting especially since it's mentioned twice. Shreditor (talk) 09:51, 6 March 2009 (UTC) "

Well stated. The challenger needs to learn about gas laws first, before commenting on them.

Have a free link.

http://lms.ctu.edu.vn/lms/courses/CNSHTT/document/p231_notes6.pdf?cidReq=CNSHTT —Preceding unsigned comment added by 81.52.240.6 (talk) 10:26, 10 April 2009 (UTC)

Article overhaul

I've just gone through and hacked about 13k out of this article, and reorganized a bunch of stuff. Before anyone panics and starts reverting, read through it and see what you think. Criticism and suggestion are welcome. Shreditor (talk) 22:30, 14 April 2009 (UTC)

Who invented the turbo and when was it first used in a car race

In the year 1902, in the Paris to Vienna motor car race, Marcelle Renault invented a Turbo and installed it onto his car and won the race. Someone needs to look over the data on who actually invented the turbo and when it was first used on a race car, as there seems to be some discrepancy on when it was first used in a race car too.

Badmoonryzn (talk) 11:07, 17 June 2009 (UTC)

Diesel engines narrow rpm range

"" Diesel engines are optimized to operate within a relatively narrow rpm range, reducing problems with turbo lag and compressor stall caused by sudden accelerations and decelerations. ""

is there a mathematical proof for this??

car diesel 600 to 5000 rpm

car gasoline 600 to 6000 rpm

hp=rpm*torque

Wdl1961 (talk) 14:02, 8 July 2009 (UTC)

You're right, that's a questionable assertion. What's needed isn't a "mathematical proof", but one or more reliable sources to support the claim. I've tagged the assertion; let's see if someone can demonstrate the assertion's veracity. —Scheinwerfermann ^T·_C14:11, 8 July 2009 (UTC)

I wrote the above text, replacing another uncited bit that was just obviously wrong. I agree it needs a cite, but it's better than what it replaced. I'll see if I can find a source. Shreditor (talk) 19:16, 8 July 2009 (UTC)

in my not humble opinion his myth is caused by the fact that diesels are used in all the heavy jobs that require almost always maximum power output like all heavy trucks industrial engines and generators and diesel locomotives . this requires more gearing or continuous electric power generation as in locomotives interspersed with no power requirements at all . anothe example of strength being changed into a weakness. a car a diesel will be just as flexible as a gasoline engine with the same load and HP. i am sure there are a lot of refs copying each other and look long enough one can find somebody . regardless of wiki refs acceptance my mind on this is closed . the universal formula used is ( high - low)/high . i may change it once after some time and that will for me be the end of it. Wdl1961 (talk) 00:41, 9 July 2009 (UTC)

I think that this is just a rule of thumb; most diesel engines sold are relatively large displacement (semi tractors and large pickup trucks), and in those applications, have a relatively low max RPM, but diesel use in passenger cars is on the rise, and those engines do have a much higher maximum RPM, and do suffer from turbo lag just as gasoline engines do. I don't have the time now, but I will try to get some numbers pulled together and add some references. Msaunier (talk) 17:22, 13 July 2011 (UTC)

I think it is kinda true; The highest RPM diesel engine I know of tops out at something like 6000rpm but normal diesel cars are normally in the 4500-5000 range. Actually usable range is much narrower; Even in my Yaris, which tops out a 5500rpm, you wouldn't run it past 3500-4000rpm even driving hard, and in normal use you'd shift at 2000-2500rpm. By comparison, petrol engines have been run into the 18,000rpm area; Even my brother's Corolla can rev up to something like 9000rpm (And doesn't even hit 'lift' with the valve timing until something like 6000rpm!). Petrols are very gutless at low RPM compared to diesels so you generally have to run them up to higher RPMs to get power out of them - You use MUCH more of the available rev range in normal driving use. Diesels OTOH have all their power at the low and mid of the rev range, so the used power band is a lot narrower. -- 92.234.58.169 (talk) 22:29, 16 February 2014 (UTC)

The lower speed of a diesel engine is to do with the the way the fuel burns under compression. As diesel fuel is injected into the highly compressed air it doesnt ignite immediatley. The initially 'cold' fuel begins to warm and disassociate until it ignites and the flame fronts move through the rest of the mixture. This takes some time and above somewhere above 5000rpm you start to reach the point at which not all the fuel will be burnt by the time the exhaust stroke is reached, limiting the speed. — Preceding unsigned comment added by 192.149.117.67 (talk) 05:34, 20 December 2018 (UTC)

Production automobiles / Citation needed

Does Citation needed refer to Peugeot and M-B as first production automobiles or "Today, most automotive diesels are turbocharged"? It may be hard to find research numbers for claim "Today, most automotive diesels are turbocharged", but at least in Europe no vehicle maker has introduced new diesel-engines without turbo since end of the 1990's. Ford, VW, Toyota etc all have been using turbos in their production diesel-engines for say at least last 10-12 years, after introduction of direct injection diesels in about 1.0L to 3.0L displacement range. Therefore, I think it's reasonable thing to remove "Citation needed", if it refers to "Today, most automotive diesels are turbocharged". There are certain things that are common knowledge, just like "it's dark in the night". —Preceding unsigned comment added by 84.239.138.83 (talk) 08:04, 20 December 2009 (UTC)

Compound Turbocharging vs. Sequential Turbocharging

The section on sequential turbocharging is mostly correct, but the advent of ball bearing turbos has made this obsolete (since ball bearing turbochargers spool up much faster). Some newer diesel engines use compound turbocharging (not sequential), which means that one turbocharger feeds air into a second turbocharger. If there are no objections, I will add a section on compound turbocharging and correct the sequential section. Dusty duster (talk) 00:57, 23 December 2009 (UTC)

Saab?

Talking about turbo technology in automobiles, Saab is the first carmaker to come into my mind...I think it was the fisrt automaker who moved to a mass production of turbocharged petrol engines... [1] —Preceding unsigned comment added by 85.75.114.183 (talk) 18:30, 15 January 2010 (UTC)

Last sentence of Pressure Increase

I believe this sentence "To obtain more power from higher boost levels and maintain reliability, many engine components have to be replaced or upgraded such as the fuel pump, fuel injectors, pistons, valves, head-gasket, and head bolts." is extraneous and is inserted without context. This is obviously referring to adding a turbo to a non-turboed engine. You would have to do these things to a naturally aspirated engine if you put a turbo on it. But there is nothing in this section talking about adding a turbo to a n/a engine and what you would have to upgrade to that engine. An engine that is designed for a turbocharger would not need any "upgrades" or "replacements." 68.98.117.11 (talk) 05:27, 17 February 2010 (UTC)Eric, 2-16-10

Charge Cooling and Temperature Considerations

There should be one section talking about the reasons and effects of charge cooling. "Charge cooling" is basically only talking about automobile applications and is very incomplete as its own section. "Temperature considerations" in aircraft is more complete, but the volumetric efficiency argument is inaccurate. Charge cooling is mainly to increase the thermodynamic efficiency because the engine efficiency is greater when the inlet temperature and exhaust temperature difference is greatest, not because the air is denser when cooler. —Preceding unsigned comment added by 68.98.117.11 (talk) 05:50, 17 February 2010 (UTC)

Comparison with Supercharging

"With a supercharged aircraft engine, the pilot must continually adjust the throttle to maintain the required manifold pressure during ascent or descent" - not true for many aviation applications. Both the Merlin & DB 605 engines had barometric (atmospheric pressure) control of boost, the pilot simply opened the throttle lever and the barometric unit continuously adjusted the actual throttle opening (RR) or supercharger speed (DB) to maintain constant engine power up to the supercharger's limit.DesmondW (talk) 16:47, 14 March 2010 (UTC)

Seems that, on the Merlin, that would only apply to a full-throttle climb. In normal circumstances, with the throttle levers partially advanced, as when climbing the Lancaster at 2650 +7, the boost pressure will drop with altitude unless the levers are advanced to maintain it. (And around 15,000ft the superchargers will need to change up to S gear as well.) Khamba Tendal (talk) 13:11, 13 January 2016 (UTC)

"Turbos are a small radial fan pump?"

The article describes a turbocharger as a radial fan pump. The discussion on this particular issue is comprised of two parts, the descriptor "radial" and the descriptor "fan pump". I wish to address the usage of "radial" without definition when it is not the most widely used or understood term. Also related to the definition statement is the term "fan pump" which is redundant and incorrect as the terms are used today.

Turbochargers operate in some type of gas working fluid which passes through both portions of the turbocharger, compressor and turbine. Consider the turbine and compressor as seperate stages and it is clear that the working fluid enters the compressor wheel on axis and exits perpendicular to the axis. Thus the use of the term "radial compressor" is acceptable, however I propose that the usage of the geometric terms "axial compressor", "radial compressor", and "centrifugal compressor" be defined within the statement due to high level of reader confusion. If the turbocharger is considered as a whole the flow of the working fluid is entering on axis and exiting on axis and one could erroneously presume that since the flow is axial. It is important to break the stages apart and investigate how the energy is added or taken away from the fluid, which leads to questioning the term "radial fan pump" in the context of the mechanisms at work within turbochargers.

Since "radial compressor" is used less frequently than "centrifugal compressor" when describing a turbocharger one of two things needs to exist; either an in-line definition statement to reinforce the term "radil compressor" should be used, or the term "centrifugal compressor" should replace "radial compressor." This might seem overly specific since the terminology is technically correct, but this it not a technical detail correction but rather a documentation correction intended to increase understanding by the reader. The reason I feel that this is also more correct is that there are many radial compressors which do not rely on the change in angular momentum to produce their effects, whereas angular momentum change is the primary mechanism behind the compression within a turbochargers compressor stage.

The term "fan pump" is redundant and incorrect technically. A fan refers to either a centrifugal or axial flow used to move a low density working medium. Pump is used to describe a device which moves a higher density medium, or a medium which resists flow signifigantly, with no consideration as to the type. In both these cases the working fluid undergoes very little compression. In fans there is no mechanism for increasing pressure and in heavy fluids compression doesn't typically occur.

Compressors are similar to fans and pumps in that they move a working fluid adding energy to the fluid as it passes, but compressors signifigantly increase the density of the working medium as the medium passes the compressor. By these widely accepted but admittedly subtle differences in definition, the turbocharger can operate as a fan at ultra slow speeds but it is avoided intentionally. The desired operation of a turbocharger is as a compressor and it's operation as a fan is considered a flaw.

So, to summarize, turbochargers are not fans nor pumps when considerd in the context of thermodynamic machines, and the term radial compressor is confusing and not precise enough for a definition statement. Though centrifugal compressors are a subset of radial compressors, the term centrifugal compressor is more widely used and understood. A turbocharger is a device which mechanically couples a working medium in two different states through centrifugal expansion and compression. More simply, a turbocharger is a centrifugal compressor joined to a centrifugal turbine.

New turbocharger designs incorporate transitional effects and are more generally described as turbine powered centrifugal compressor, though both the compressor and turbine can be mixed-flow hybrids resulting from fluid effects related to centrifugal/radial and also axial effects. This discussion should be moot within 10 years as multi stage mixed mode compressors and turbines already exist today. —Preceding unsigned comment added by 216.51.192.237 (talk) 10:17, 13 May 2010 (UTC)

superchargers vs. Turbo superchargers vs. turbochargers

Solving the editing in this article seems to be confused. Unless someone can explain otherwise this article should be updated as follows: superchargers are direct mechanically driven positive displacement devices used to increase the effective volumetric efficiency of Otto and diesel cycles. Turbo superchargers are direct mechanically driven continuous flow dynamic Turbo machines used to increase the effective volumetric efficiency of Otto and diesel cycles. Turbochargers are continuous flow dynamic Turbo machines driven by turbines used to increase the effective volumetric efficiency of Otto and diesel cycles. What is the general consensus relative to the above point of view?Mkoronowski (talk) 05:03, 12 May 2011 (UTC)

Your definitions seem too technical, and the definition for "turbo supercharger" is confusing, as the term appears to have several meanings. We also need to cite reliable sources for the definitons, which the Nomenclature section of the article does not yet have. - BilCat (talk) 09:12, 12 May 2011 (UTC)

you make 2 great points. both of which i would like to discuss more.turbomachinery, of which turbochargers are a part is based upon mountains of applied mathematics. it is "rocket science". there are ways to simplify the discussion of the technology, especially to introduce to article. but the problem is that there are contributors that know nothing of the real theory and insist that their "old wives tale" is fact. if the average person can't understand the navier-stokes equation page, or the gas properties page, why should the the technical discussion of turbochargers be simplified?

next you mention turbosuperchargers being confusing. turbochargers are known, loved and well defined. superchargers are known, loved and well defined. turbosuperchargers is a word made up for sales reasons. for a machine we call turbochargers today. turbosupercharger is a colloquialism and has historical significance, yet people insist on using in a confusing way. we should say (A)turbosuperchargers = turbochargers [x,y,z] or (B)turbosuperchargers are different from turbochargers cause of references x,y,z or (C)turbosupercharger has multiple meanings [x,y,z]. i don't care as long as it is clear and referenced by a legitimate source. what is your opinion here?Mkoronowski (talk) 15:20, 12 May 2011 (UTC)

Actually the terms were originally supercharger and turbo-supercharger - turbocharger is a later shortening of the turbo-supercharger term. The latter two use the term turbo in the same manner as it is used in turbojet - because they use exhaust turbines to power them.

Supercharger - mechanically powered, usually via the crankshaft

Turbo-supercharger (or turbocharger) - powered by an exhaust-turbine

Incidentally, the term supercharge was originally a naval gunnery term, denoting an additional propellant charge added to obtain increased range from a large naval gun such as carried on battleships. — Preceding unsigned comment added by 80.7.147.13 (talk) 10:56, 27 May 2012 (UTC)

This shouldn't be a contentious issue. All forced induction devices work by increasing brake mean effective pressure (BMEP). The BMEP is determined by the mass flow and pressure ratio of a piston engine. In other words, stuff more air and fuel into a piston engine, then squeeze it tighter to get higher cylinder pressure during combustion (i.e. BMEP). Functionally, the BMEP of a piston engine is determined by the compression ratio and cylinder charge density. In naturally aspirated engines, cylinder charge density = ambient air density - pumping losses.

Forced induction development followed a process of picking the lowest hanging fruit. The simplest forced induction system adds energy to the induction air to overcome pumping losses. Early systems used mineshaft ventilators from the Roots Blower Company. This device increases charge density by adding enough velocity to overcome friction caused by pumping losses. Hence, pumping losses are mitigated, cylinder charge density approaches ambient air density and the Roots "blower" was born.

Increasing air density above ambient requires more complex manufacturing processes than "blowers." Aviation spurred the need of "supercharging" the induction air density since horsepower is lost as air gets thinner with altitude. Supercharging refers to increasing the cylinder charge density above ambient air density. Supercharger refers to the actual air compressor, which can take many forms (e.g. centripetal, reciprocating, scroll, wave, screw, resonant).

Likewise, superchargers can be driven multiple ways (e.g. engine, turbine, motor, wave, resonance). The pre-WWII British air force favored and heavily developed engine-driven superchargers. The pre-WWII American air force favored and heavily developed exhaust turbine-driven superchargers (i.e. turbo-superchargers). Turbo-supercharger colloquially became "turbocharger" just like International Business Machines became "IBM." 75.51.68.141 (talk) 05:15, 8 March 2014 (UTC)

temperature considerations and comparisons to supercharging

these 2 sections play very loose with the technology and results in an inaccurate non neutral point of view. point of fact is there is spinning going on. it will be very difficult to rewrite worst 2 paragraphs because the conclusions are false. yet, they bring up well informed facts that are interesting and valuable in a different dialogue. It almost seems like 3 authors climbed all over each other to cook up a serving of mashed potatoes with peas and corn mixed in. the author who suggests that superchargers are power parasites is correct only with respect to a very specific technical point. the statement that turbos don't do this is correct. the implication that turbos are thus free from this sin is a very gross error and is ignorant of any basic thermodynamic understanding. turbos waste a portion of the power that they could generate via exhaust back pressure. supercharging while more punishing of the hardware can be more efficient because of an efficient drive system.Mkoronowski (talk) 18:34, 14 May 2011 (UTC)

what is this article about

It has just occurred to me that automobile enthusiasts are using the turbocharger article to detail the use of turbochargers and automobiles and automobile racing. It would seem to me that I would be appropriate to start new articles on turbochargers in automobile performance. I think there's a need to look at this further.Mkoronowski (talk) 03:50, 17 May 2011 (UTC)

organization and current revisions

while not a turbocharger expert, it is evident that the turbocharger article was a mess. multiple threads of logic where presented. the outline is updated and paragraphs resorted. a few technical errors are being corrected. please help consolidate sections where ever possible. 2 paragraphs with a skewed point of view were removed, as they represented a historical opinion that had little to do with turbochargers.Mkoronowski (talk) 18:47, 19 May 2011 (UTC)

not an auto enthusiast dumping ground

the use of turbochargers neither begins or ends with automotive applications. equal voice should be given to all applications. is there enough room to cover all applications equally? the answer is likely no. the answer is likely sub articles, each addressing the unique interests of that application. such as aircraft turbochargers, locomotive and marine diesel turbochargers, truck turbochargers and automotive turbochargers. in this way the main article turbochargers can deal specifically with turbos and briefly introduce the wide variety of applications. turbochargers are actually turbo-machines that enhance primarily otto and diesel internal combustion engine performance. think tooth brush, is anyone interested in who uses a tooth brush? the article on tooth brush does not have your name in it. Mkoronowski (talk) 22:26, 22 May 2011 (UTC)

formatting units

is it wiki standard to say 5 ft and at the same time say 5m? note the space before ft and no space before m.Mkoronowski (talk) 19:17, 23 May 2011 (UTC)

Merge turbosupercharging and this page

Turbosupercharger is an obsolete term for a turbocharger - they are the same thing. Both the (orphan) turbosupercharging page and the supercharger page support this, and in fact, turbosupercharger redirects to turbocharger; you have to specifically search for turbosupercharging. I think that all of the content there could be added as, essentially, a historical footnote here. Msaunier (talk) 15:14, 9 July 2011 (UTC)

• As there has been no discussion on this, I'm going to add merge templates to both articles. I will take no further action for a week or so to allow time for debate. If you disagree, here's the place to do it. Msaunier (talk) 17:25, 13 July 2011 (UTC)

Support the merge - CZmarlin (talk) 17:21, 17 July 2011 (UTC)

No Mechanic Load?

"In comparison, a turbocharger does not place a direct mechanical load on the engine" <- This is form the unsourced section comparing turbocharges to superchargers. I know that turbocharges put less mechanical load on the engine than superchargers, but they should put some, as the pistons will have to be pushed harder into he exhaust stroke by the flywheel.

In a more general sense, for the entire article, it seems to be trying to portray turbochargers as being 100% powered by waste heat. This is just not true from everything I have been lead to understand about them. They are powered by waste heat AND back pressure. Largely waste heat, true, and they can drop exhaust temps considerably, but not all waste heat.

Am I missing something here? Even if they are miraculously 100% fed off of waste heat (which I am almost certain is not the case), it would need to be documented. --Electrostatic1 (talk) 12:01, 17 August 2011 (UTC)

This all sucks, and it has been on my rework list since last year. I can't fix turbocharger (too many teenagers with "World's Fastest Cars" coffee table books), but turbo-compound engine still needs sorting.

Turbochargers for power boosting at sea level really begin with Sulzer's work in the 1930s, not Rateau's earlier efforts. When developing high-pressure supercharged diesels (NB, it's not the same for petrol) it was found that it was possible to produce a diesel engine that produced huge amounts of thermodynamic power, but the limit on deliverable shaft power was then the ability to extract this power from the hot gas, by doing work on a piston when expanding the gas. When compression was being provided significantly by the external supercharger rather than the piston's compression, the engine is heading for a regime where it can't avoid leaving much of the energy behind in the exhaust - even at BDC, the combustion gases are still hot and at high pressure.

The first solution was a turbo-compound engine. An exhaust turbine was added, so as to extract the heat energy that wasn't accessible to the piston. This worked, but turbo-compounds have the engineering problem of coupling a fast turbine to a slow crankshaft. It was soon realised that if the turbine had excess power available that was difficult to use through the crankshaft, and that if the compressor was in need of maybe a third of the engine's thermodynamic output to drive it, then the obvious solution was to decouple both from the crankshaft and drive the compressor directly from the turbine. As the compressor for these engines was already likely to be centrifugal, not a Roots blower, this was an easy match in terms of shaft speed already. Thus the turbocharger, as we know it today, was born.

Turbochargers do not place a "mechanical load" on the engine, because we define such mechanical loads as being shaft power delivered through the crankshaft. It's more useful (as engineers) to have a simple term for this than it is to nit-pick over etymology, so that's what we do. No one is claiming that they don't increase restriction to exhaust flow, just that we account for that under a different description.

Similarly it's unhelpful to separate "waste heat" and "waste pressure". They're related through the gas law, so one trades directly for the other. Neither is counted as "mechanical" power in this context. Andy Dingley (talk) 13:40, 17 August 2011 (UTC)

• Backpressure is an indirect mechanical load, as supposed to say something driven off the crankshaft; but you're right that it's important to point out that the energy used for compression is not free. —dgies^t_c 00:03, 9 November 2013 (UTC)

Honeywell Contributions

{{request edit}} I have a paid COI with Honeywell. I would like to help improve the page following COI best practices. I respect the community's autonomy, understand the rules and would like to collaborate with neutral editors that share an interest in providing encyclopedic information on the topic to the public, consumers and aftermarket users.

For starters, I've collaborated with Stanford's Department of Chemistry, who had published a diagram showing how a variable geometry turbocharger works. I received permission to upload under a creative commons and the image is available here. Combined with a great annotation, it could really help communicate the concept.

User:King4057 (COI Disclosure on User Page) 03:26, 17 March 2012 (UTC)

Done I added the image (with no annotation) to the 'Operating principle' section. If you have an idea for an annotation, feel free to post it here and/or let me know. Thanks!   — Jess· Δ♥ 07:23, 26 March 2012 (UTC)

Sources

1. How Stuff Works [2]
2. Automotive News [3]
3. The National (road test) [4]
4. CNN [5]
5. Stanford [6]
6. Turbokart [7]
7. The Gazette[8]
8. Turbocharging Performance Handbook [9]

1 & 2 discuss giving smaller displacement engines the same power of their larger counterparts, while 3, 4 & 7 discuss specific vehicles that did just that. The Stanford source #5 has a lot of academic metrics on turbocharger performance. This is the source I obtained image permission from. Hope these are helpful. User:King4057 (COI Disclosure on User Page) 04:55, 17 April 2012 (UTC)

Thanks for the sources. I've put a few of them in- they could certainly be better used, but it's a start. 1292simon (talk) 11:04, 19 April 2012 (UTC)

Gale Banks

The text under "motorsport" and inclusion in External Refs smell of advertising. Maybe the land-speed record stuff would be notable on a page about land-speed records, but not here. Removed.1292simon (talk) 02:37, 22 March 2012 (UTC)

unexplained list of cars

I assume these are vehicles which pioneered turbocharging in some way? It would be good if their notability could be explained in the article.
Also, where does it stop? Would the first DI turbo engine deserve inclusion? First variable-vane? First twin-impellor? First rotary? First injected? First intercooled? (just suggestions) 1292simon (talk) 02:26, 9 April 2012 (UTC)

It's just the regular problems of recentism and bias towards favourite topics with visible sources. Very little innovation happened with road cars, and even racing cars didn't contribute much until the '80s. Before that it was extremely dull generator sets and ship engines that were where the innovation in turbochargers was happening. Andy Dingley (talk) 09:01, 9 April 2012 (UTC)

Its not unexplained list, its very clear if you read the automotive section thru, its showing who pioneered turbocharging, its very sought after info so I think it deserves to be in this article, I think the 1980 is good line, after that almoist every brand got turbos. Anyway it needs to be referenced better than now. Those "Would the first DI turbo engine deserve inclusion? First variable-vane? First twin-impellor?" can be in prose text -->Typ932 ^T·C 10:33, 9 April 2012 (UTC)

The current intro ("Cars which pioneered the use of turbocharging include") is just something I added (hope it's ok!), before that it was just a list of some turbocharged cars with no explanation about their significance. Pioneers in DI, variable-vane, etc, etc are just my suggestions for other cars which may be significant in the development of turbos. Sorry if I seem to be picking on it (you sound a bit defensive Typ932), it's just something I thought could possibly be improved. 1292simon (talk) 13:21, 9 April 2012 (UTC)

This article has much more unexplained data than this what about section "Manufacturers of turbochargers" this list has nothing at all explanations why they are in this article -->Typ932 ^T·C 10:37, 9 April 2012 (UTC)

Also in the main text is car brands with turbos that has no explanations or why they deserves to be in this article "Volvo, Saab, Audi, Volkswagen, and Subaru have produced turbocharged cars for many years; " so if if you are going to change something take car of NPOV. -->Typ932 ^T·C 10:42, 9 April 2012 (UTC)

Sure, thanks for the tips. 1292simon (talk) 13:21, 9 April 2012 (UTC)

The problem of these car articles is always, that editors are supporting their "own brands" , be it on the list or in the main text. Yes might sound a bit defensive because the list was deleted earlier by someone, before taking care of the NPOV aspect. The list is easy way to handle NPOV aspect , all brands that "deserves" creditability are easily seen and not hided between main text lines, its also very intresting info among car enthusiasts -->Typ932 ^T·C 14:04, 9 April 2012 (UTC)

motorsport

The opening paragraph ("It is also important to understand...") applies to all forced induction engines, perhaps it should be moved to the forced induction article. It could also do with the odd citation... 1292simon (talk) 14:54, 11 April 2012 (UTC)

manufacturers of turbochargers

According to WP:NOTCATALOG, I don't think it is appropriate to have a list of manufacturers (it can't possibly include anyone who has ever produced a snail, therefore it will always be biased someone). Therefore I propose this section be removed. 1292simon (talk) 14:59, 11 April 2012 (UTC)

All such lists are cruft-prone. It would be reasonable to keep it if there was some sourceable scope for why they're listed, such as innovation.

Otherwise we might as well replace it with a template and transclude the same one onto hydraulic cylinder, gearbox and alternator too - list some well-known UK & US manufacturers that haven't made anything themselves for decades and are now more of a clothing brand than a factory and tack on the same old list of all the Japanese, Korean & Chinese zaibatsu who are now so big that that all simply make everything. Andy Dingley (talk) 15:41, 11 April 2012 (UTC)

No objections so I'm gonna delete it. If fanboys want their brand mentioned, they can always justify its significance by finding somewhere that it has advanced the science and slip it in there (ala Garrett for the Merc 300SD) 1292simon (talk) 09:59, 13 April 2012 (UTC)

Often a list of vendors is used when a "Business" section might be better. Any topic that is also a product has a business element, a market-size, projected market, competition and so forth. I've also come along this source[10] in my Honeywell work, which discusses that Honeywell and BorgWarner are "vying for domination." From what I've heard, there are no publicly available, exact market-share numbers. Contributing to general cleanup while following Bright Line is tough, but I can contribute a Business section if it would help. See my COI disclosure above. User:King4057 (COI Disclosure on User Page) 04:37, 17 April 2012 (UTC)

Thanks, King4057. I agree that a Business section would be useful. It's a bit of a stub at the moment, let me know if you have ideas to expand it (eg any big mergers/buyouts/bankruptcies/etc?)1292simon (talk) 09:20, 19 April 2012 (UTC)

Effect of altitude

I believe the text about compensation for altitude is most relevant for aircraft applications. Therefore I propose to move this content from Operating Principle to Aircraft Applications. 1292simon (talk) 11:30, 19 April 2012 (UTC)

turbosupercharger

I believe the classification of a turbo as a type of supercharger is outdated (link), the current terminology is "forced induction" (which has been adopted to reduce confusion). Therefore I believe any references to turbosupercharging or "turbo is a type of supercharger" should be confined to the History section.1292simon (talk) 21:37, 24 April 2012 (UTC)

However you haven't done this, you've deleted it entirely.

Ihave two interesting books on my bookshelf here, Turboblowers (1955) and the well-known Modern Gas Turbines (1947) by A.W. Judge, which is largely about turbos, rather than what we'd now term gas turbines. "Turbosupercharger" isn't the only term of historical significance that's now unfamiliar. Andy Dingley (talk) 01:00, 25 April 2012 (UTC)

See the History section, it's covered there. No complaints from me if you want to add other superseded terms to the History section. 1292simon (talk) 02:36, 28 April 2012 (UTC)

I think the statement that "it is formally known as a turbosupercharger" requires recent sources to be included. 1292simon (talk) 11:11, 20 May 2012 (UTC)

direct drive vs exhaust gas, positive displacement vs kinematic

I am confused by the terminology used in the turbocharger article. there are centrifugal compressors driven by energy from exhaust gas. this seems to be called a turbocharger. there are positive displacement compressors driven by mechanical shaft energy. this seems to be called a supercharger. there are centrifugal compressors driven by mechanical shaft energy. what do you call this?

	centrifugal/kinematic	roots/positive displacement
exhaust turbine	turbocharger	???
gear/chain/belt	???	supercharger

Mkoronowski (talk) 23:06, 10 July 2012 (UTC)

They're all 'superchargers'. Centrifugal superchargers are termed just that, 'centrifugal superchargers'. Those driven by gas turbines, rather than mechanical coupling, are termed 'turbosuperchargers'. This is usually shortened to 'turbocharger' or 'turbo'. Andy Dingley (talk) 23:29, 10 July 2012 (UTC)

Merge of Turbocharged petrol engines

They have been tagged for merge, but no rationale has been posted.

• oppose Turbocharger's scope is much broader. The engines article can also useful cover issues of mechanical supercharging in petrol engines, not just turbocharging.Andy Dingley (talk) 09:04, 17 September 2012 (UTC)

• oppose turbocharger is already a large article. It would become unwieldy if the level of detail from "turbocharged petrol engines" was added. Also, petrol turbo car engines is a notable topic in its own right. 1292simon (talk) 05:35, 30 September 2012 (UTC)

I oppose the addition of Turbocharged Petrol Engines. That is a whole other discussion and topic. The turbocharger is a complex beast, and the article could stand to be expanded as of today's article. I would like to see more citations than are currently on this article.02:20, 27 February 2013 (UTC)Julie Polak. — Preceding unsigned comment added by 71.84.11.190 (talk)

error present in the operating principle of turbocharger (?)

This feedback came through the Wikipedia mobile site - I no nothing about this subject but thought I'd forward you his feedback in case it was useful.

I would like to bring to your notice about an error present in the operating principle of turbocharger. Let me know if you require any clarification.

http://en.wikipedia.org/wiki/Turbocharger

Operating principle

Error : This is achieved by recovering waste energy in the exhaust and feeding it back into the engine intake.

Truth: This is achieved by recovering waste energy in the exhaust and rotate the compressor to compress the air into the engine intake. — Preceding unsigned comment added by Jdlrobson (talk • contribs) 21:08, 21 September 2012 (UTC)

The section on blow off or dump valves is factually incorrect. The main reason to use a bypass valve is to maintain the compressor above its surge line. A single flow reversal is possible, however repeated cyclic oscilations are caused by the flow falling below the surge line which leads to a collapse in pressure rise, a subsequent collapse in flow followed by a pressure rise & flow recovery until flow falls back below the surge line and the cycle repeats. Needs Rewrite. — Preceding unsigned comment added by 192.149.117.203 (talk) 12:07, 18 August 2014 (UTC)

US heavy bombers and turbochargers?

I've just reverted this:

"The great majority of World War II American heavy bombers used by the USAAF - particularly the Wright R-1820 Cyclone-9 powered B-17 Flying Fortress, and Pratt & Whitney R-1830 Twin Wasp powered Consolidated B-24 Liberator four-engined bombers both used similar models of General Electric-designed turbochargers in service, as did the twin Allison V-1710-engined Lockheed P-38 Lightning American heavy fighter during the war years. "

Emphasis mine. Now I agree that this statement is worth making, and the P38 certainly stands up. However the sticking point is the B17 and particularly that "great majority" claim. Wasn't the Cyclone a mechanical supercharger, albeit centrifugal, rather than a turbocharger? Andy Dingley (talk) 13:12, 26 February 2013 (UTC)

OK, I've restored this, as it's citeable. However our engine articles need work! Andy Dingley (talk) 13:19, 26 February 2013 (UTC)

turbo

ข้อเสียของ turbocharger (ไร้ข้อดีของ turbocharger) ในทุกยี่ห้อ เครื่องยนต์เบนซิน ติดตั้ง 1-4 turbocharger พร้อม intercooler เป็นเทคโนโลยีที่ล้าหลังไป 200 ปี ต่อให้เครื่องยนต์เบนซิน ติดตั้ง 1-4 turbo พร้อม intercooler ในยุคปัจจุบัน ก็ยังล้าหลัง เป็นรูปแบบที่ไม่ประเทื่องปัญญาในด้านวิศวกรรม เนื่องจากเป็นรูปแบบที่ทำให้เครื่องยนต์เบนซิน ติดตั้ง 1-4 turbo พร้อม intercooler เสื่อมประสิทธิภาพเชิงกล 90 % ไม่สามารถใช้แรงขับเคลื่อนได้ 100 % มีอัตราสิ้นเปลื้องเชื้อเพลิง 1-5 กม. ต่อ ลิตร(มากกว่า 20 ลิตร ต่อ 100 กม.) และต่ำกว่า 1 กม. ต่อ ลิตร (มากกว่า 100 ลิตร ต่อ 100 กม.) และแพ้เครื่องยนต์เบนซิน ใหญ่กว่า ปราศจาก turbocharger intercooler ในทุกด้าน กับเครื่องยนต์ เบนซิน supercharger intercooler ตามกรณีแรงม้าเท่ากัน แรงบิดเท่ากัน — Preceding unsigned comment added by 124.121.222.143 (talk) 09:52, 5 December 2013 (UTC)

The following was intended to be a separate entry, not appended to the above.

The opening line, which should be defining, is wrong and misleading - simply "forcing extra air into the combustion chamber" won't of course increase power. Yes, it's (maybe) clarified in the second line, but why not get it right to start with? I even feel Webster's definition <<www.merriam-webster.com/dictionary/turbocharger>> is inadequate. I would suggest something like "(Compared to naturally aspirated engines,) a turbocharger increases an engine's power by using an air compressor to achieve the loading of a greater air/fuel charge, (on each cylinder's intake cycle). It does this by....".

Don't forget, people who know nothing about the subject will read the first line and take it as rote, expecting/hoping further lines will elaborate. If the first line is wrong, they're off to a bad start. 19/07/201449.185.110.210 (talk) 06:00, 19 July 2014 (UTC)

Images

I think the images, especially those early in the article, don't really put the turbocharger in relation to the overall engine very well. — Preceding unsigned comment added by 82.139.87.10 (talk) 19:47, 10 May 2015 (UTC)

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The https://web.archive.org/20150402123651/http://reviews.cnet.com/8301-13746_7-20045466-48.html link redirects twice and ends up on https://web.archive.org/web/20150403085733/http://www.cnet.com/news/turbo-title-honeywell-or-borgwarner/ which does talk about turbochargers but does not support the text in the Wikipedia article, at least not the first time it is referenced. As the original reference also lacks any kind of title and other information (it was just a plain URL) it should perhaps just be deleted. By the way, the {{sourcecheck|checked=false}} is not thought through – what to do if it was actually checked but turned out not to work? --Jhertel (talk) 20:46, 29 August 2015 (UTC)

List of turbocharged automobiles?

Is there a list on wikipedia somewhere? It out to be mentioned/linked in this article. --RThompson82 (talk) 02:54, 8 May 2016 (UTC)

• strong oppose Turbochargers are commonplace. Such a list would be long, inevitably incomplete, and would collapse into the inevitable wiki listcruft of "I want my car on this list". There is nothing inherently noteworthy for a car of the last 20 years having a turbocharger. I doubt if this even has much significance as a category - more robust categories have already been deleted in the past.

The closest useful list to this would be some sort of timeline of turbocharger adoption, listing the novel, early and significant introductions of turbos. A feww cars for that might include the Corvair, the Audi Quattro, the BMW 2002 ti, Renault 5, the MG Maestro Turbo, the Maestro diesel turbo and others, all of which had some historical significance to their adoption of it. Andy Dingley (talk) 09:04, 8 May 2016 (UTC)

=T1 vs T2 vs ??

I'm trying to figure out the competition parts availability. In the current vernacular there are a lot of references to T1, T2, and T3 Turbos for automotive applications. Is the T1 designation a reference to a one stage turbocharger? .. the T2 to a two stage Turbocharge, etc. — Preceding unsigned comment added by 50.240.2.125 (talk) 22:04, 11 October 2018 (UTC)

Error in "Turbocharging versus supercharging"?

The last paragraph of this section states something like "two stroke engines cannot naturally aspirate". I've seen a lot of naturally aspirated two stroke engines that seem to belie the statement. Does anyone have insight to what the author may have meant? I would simply change it but would like some reinforcement in case I'm missing something. Thanks. — Preceding unsigned comment added by Al Legato (talk • contribs) 07:31, 26 December 2018 (UTC)

E-Turbos

I have added a E-turbo section to this page as I feel that this technology is becoming a lot more feasible, and we may start to see it in production cars within the next 5-10 years. There is already a page specifically for e-turbos but it is very short and non descript. I believe the Normal Turbocharger page is a better place for this info anyway, since it is a variant of the traditional turbo. Also since it is newer technology, many people may not know about it, especially those who are just learning about it. — Preceding unsigned comment added by Mconor47 (talk • contribs) 01:21, 25 February 2021 (UTC)

The new section is good. One thing I don't get is how it reclaims electrical energy. Does it have a generator in addition to the electric motor on the turbine shaft? Or does the electric motor also work as a generator when it is not driving the compressor? Or something else?  Stepho  talk  15:52, 25 February 2021 (UTC)

Thanks! It was my first entry on here. I agree, I was a bit vague about the way in which it reclaims energy. This was because I was able to find little information about how it was done. I got lots of info from garret, as they seem to be making good progress with e-turbos, and their website says "under investigation" under the "recuperation potential" category. I have requested a PDF going further into depth about this technology, but I feel I will not get it since I'm still only a student. — Preceding unsigned comment added by Mconor47 (talk • contribs) 18:37, 25 February 2021 (UTC)

Eturbochargers

This section mentions the Garret eturbo and that it's not clear how they will work.

However, this technology has been used for years in formula 1 engines. It's called the MGU-H (Motor / Generator unit - Heat)

https://f1.fandom.com/wiki/Motor_Generator_Unit_-_Heat

It is referenced on wikipedia in the formula one engine page: https://en.wikipedia.org/wiki/Formula_One_engines

Basically this technology is developed and works already. I have never edited an article and don't have an account but if it's kosher to do so I will add this detail to this section — Preceding unsigned comment added by 73.115.132.9 (talk) 02:08, 11 December 2021 (UTC)

Anybody is allowed to edit - so have a go. We'll lend a hand via advice or corrections if you needed.  Stepho  talk  09:43, 11 December 2021 (UTC)