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- 1 Heat of compressed gas
- 2 Relative efficiencies
- 3 Hydrogen compressor
- 4 Air quality test
- 5 Reason for changing photograph
- 6 How do Thermal expansion or Decompression relate to Gas compressor ??
- 7 Split air conditioner compressor
- 8 Air end (also spelled as airend)
- 9 Turkish Wikipedia user Metal Militia has been giving wrong information on "Compressor" subject in Turkish version
- 10 conservation of energy
- 11 Error in "Axial-flow Compressor" section?
- 12 OK?
- 13 Guided Rotor Compressor & Rolling Piston Compressor?
- 14 Optimal efficiency
- 15 "Un-noteworthyness of quasiturbine"
- 16 Link to in-depth articles
- 17 Normal and standard temperature and pressure
- 18 "Heat of compression"
Heat of compressed gas
The heat of a compressed gas does not come from the inefficiany of the machine compressing the gas. I am not sure why you insist on this error but I am not going to get into an edit war with you Mark.
A great and well respected company to get a compressor from is Ingersoll Rand. —Preceding unsigned comment added by 220.127.116.11 (talk) 20:26, 13 August 2010 (UTC) —Preceding unsigned comment added by Qaz (talk • contribs) 4 March 2004 (UTC)
Can anyone provide any figures for the relative efficiency of the various designs of compressor? This is information I for one would find extremely useful.--18.104.22.168 23:55, 16 June 2006 (UTC)
- I second the request of the above person. It would seem to me that a piston design would produce much lower efficiencies than a turbine design, but just how much better or worse? I've dug into my thermo books, and can't seem to find anything on excpected mechanical efficiencies. ~ZirbMonkey - 27 June, 2006 read it by Badr AL-Sowayan
- I third the request, please. Hanlon's book isn't in any library I can find within 50 miles.Egmonster 05:05, 7 July 2007 (UTC)
- It is very difficult to provide the "relative efficiences" requested above. First of all, there many differnt types of efficiency in use, for example: adiabatic efficiency, isentropic efficiency, polytropic efficiency, isothermal efficiency, volumetric efficiency, mechanical efficiency and overall efficiency.
- Then there are certain parameters that affect the efficiencies, for example, the specific compression ratio and the percentage of load at which the compressor is operated.
- As a generalization encompassing all the many types of compressors and all of the parameters that affect the efficiency, the range of adiabatic efficiencies is from 45% to 95%. Sorry, but I just cannot do any better than that. Perhaps someone else may have a better answer. - mbeychok 21:08, 7 July 2007 (UTC)
- In the gas turbine business, efficiencies are usually quoted at the design point (often peak efficiency) and as polytropic efficiency which normalises for compression ratio. Decision on which type of compressor to use usually depends on flow rate and pressure ratio required. However, axial compressors are slightly more efficient (up to low 90s) than centrifugal (high 80s) for flows greater than a certain size. Of course, any benefit in efficiency comes at a cost.AlekH (talk) 23:30, 15 February 2008 (UTC)
The section, hydrogen compressor is missing. Mion 16:47, 31 July 2006 (UTC)
Air quality test
I need help. Carrying out an Air Quality Test of air compressed into an SCBA cylinder. The water value reads 180mg/m3. The cylinder is 9kg in size. The Standard required in the vessel where I work (FPSO is 30mg/m3. How is this possible for God's sake! Give me a clue. The test time is 10 Minutes using Drager kit. The instruction in the water tube is of October 2005. Is there a way of converting mg/m3 to ppm? Pls let me know. My email address is: firstname.lastname@example.org —Preceding unsigned comment added by 22.214.171.124 (talk • contribs) 9 January, 2007 (UTC)
- Read this Wikipedia article: click here ==> Useful conversions and formulas for air dispersion modeling#Converting air pollutant concentrations. It has exactly what you are looking for. - mbeychok 18:25, 19 January 2007 (UTC)
Reason for changing photograph
I replaced the original photo with a better one of a single-stage centrifugal compressor because I thought the original photo was a rather scruffy looking photo of small portable air compressor. I think the photo that I used is much cleaner and neater, and more representative of the thousands of compressors in industrial use. If anyone has a better one in color, that would be better yet. - mbeychok 08:03, 19 January 2007 (UTC)
How do Thermal expansion or Decompression relate to Gas compressor ??
I think that some of us get carried away with providing Wiki links. I just read the Thermal expansion article very thoroughly. It is obviously about the thermal expansion of liquids and solids. I fail to see any relation between that article and this article on Gas compressors. The lead-in sentence of this article about gas compressors states: A gas compressor is a mechanical device that increases the pressure of a gas by reducing its volume.
An article about the thermal expansion of liquids or the thermal expansion joints in bridges and railroads has no absolutely no beneficial connection whatsoever with this article. Wiki links in the "See also" section are meant to point the reader to related articles with some real, beneficial connection to gas compressors.
I also feel the same is true of the link to the Decompression article. It has no connection to gas compressors. I think it behooves all of us, myself included, to be more careful about adding unrelated links to the "See also" section of any articles. What do others think about this subject? - mbeychok 00:36, 29 January 2007 (UTC)
Split air conditioner compressor
- If it is compressing a gaseous refrigerant, then it is indeed a gas or vapour compressor. - mbeychok 15:37, 2 May 2007 (UTC)
Air end (also spelled as airend)
- A packaged air compression system or a field-installed air compression facility includes a number of components: a control panel, a motor or other driver, a suction air filter, the air compression chamber, a discharge air-lubricant separator, compressed air after-cooler, lubricant cooler, compressed air dryer, compressed air filter and a compressed air receiver vessel. The air end is the air compression chamber. See Improving Compressed Air System Performance and scroll down to page 8 of 128. - mbeychok 19:09, 26 May 2007 (UTC)
Turkish Wikipedia user Metal Militia has been giving wrong information on "Compressor" subject in Turkish version
In Turkish version of Wikipedia free Enclylopedia, the "Kompresör" subject (in English "Compressor") your some internal users (of Vikipedi/Turkey) like a guy with Metal Milia nick name and some others, have been spoiling correct information and redirecting the Compressor subject to gas compressors wrongly.
Many times i had corrected the mistake and i had written Compressor subject in Turkish with my 17 years experience on Compresssor production and technical document translation.
I had written a very good atricle and simple but detailed information and explation of compressors, air compressors with my own world and private informtion as free support article to Wikipedia project as i had noticed on the article.
I had prepared the article a mixcing of my expereience and full original principles and information from leading compresıor manufatures. But article was full free and original by me. it was not a copy/paste or copyright violation.
(refencences: BCAS Compresssed Air Guide, Compressed Air Compendium, Turkish Mechanical Engineers Chamber Book "compressors", Compair BroomWade, Cooper Cameron etc. compressor manufacturer's common/publich product information. And of cource, full original information by me... as private..)
I am sure my article was 100% correct and no body could say it as wrong information or details.
At first, somebodies who say we are competent of turkish vikipedia, detletd my article and put a wrong or defective information instead of it.
They wrote me, you did not notice your information page -article- has GNU GPL. I wrote them, my article is full free by me... I tis nly by me... Ther is not need to declare GNU GPL because of wikipedia author of information is me, and it is only a wikipedşia subect there is no copy of it in anywhere expet wikipedia itself...
Even if I say, my article is recent best explanation in compressor subject in Turkish, you must support it with images and other corrections.
due to possible competition purpose (to prevent common access to information by me) -these guys may be working for competitor companies in Turkey which are manufactiring compressors as comperetior to the company which i am working for...) [ Even if i dont do advertisment of the comany... They -may be- want to prevent customers access to me by this article... ]
"kompresör" keyword is under common advertisment request in google search motor. And turkish "kompresör" subject of wikipedia encylopedia is on the first page of the searched/found pages.
Before they spoiled the article... It was a link to my non-professional web ste sections in non-profession singlix web site. These web pages have information about compresors and compressed air.
So, at the beginning of the compretition attack they erased thesinglix web site kompresor section link on wikipedia "kompresör" article...
Then they eraded the complete arti,cle and they put a wrong and short (defective) article instead of full usefull information on engineering level. The current information is just a like a first school explation of compressors. But, we know the information oabout compressors is needed by engineers and technicians, commonly... (Compressor information is not a first school or children lesson subject, so it was prepared by experinced engineers.)
I am an experienced mechanical engineer and expert on Compressors and compressed air subjects.
I am very sad due to somedies deleted my article without honesty or without sicientific/technologic correction requirements.
In Turkey, usually, non qualified and non sufficent people have competent rights. Just as yout turkish vikiedy editors (competent users) Metal Militia and others who write compessor or gas compressors article without what is compressors and gas compressors, enoughly.
Please interfe to turjish vikipedi project against the wrong staff employment/organizationing/building.
Also, i would like to see correct information on "kompresör" subject just as i had written on/about it. on Wikipedia pages...
conservation of energy
one thing we should keep in mind, all gaseous and liquid compression / expansion processes are governed by the energy equqtion .
Error in "Axial-flow Compressor" section?
The section says:
- "The rotating aerofoils, also known as blades or rotors, decelerate and pressurise the fluid. The stationary aerofoils, also known as a stators or vanes, turn and decelerate the fluid; preparing and redirecting the flow for the rotor blades of the next stage."
Actually, you can say both: the rotor does decelerate the fluid in the rotating frame of reference (i.e. relative to itself) if it didn't you would need a lot more stages for the same pressure rise. It also normally accelerates the flow in the stationary frame of reference (but it doesn't have to, that depends on the angle the flow enters and exits the rotor).
Is this line OK: "The inter-stage coolers cause condensation meaning liquids eg, water, gas condensate separators, known as scrubbers, with level control & drain valves are present. " 126.96.36.199 (talk) 09:50, 15 September 2008 (UTC)
- You are correct ... that sentence is rather incoherent. In fact, the whole section was incoherent and poorly structured. Too many cooks in the kitchen. I have re-written the entire section and made it more coherent (I hope). mbeychok (talk) 04:59, 16 September 2008 (UTC)
Guided Rotor Compressor & Rolling Piston Compressor?
Anyone familiar with a compressor type called a guided rotor compressor?
I found a reasonablly detailed description of what sounds like a new compressor technology at http://www.grcompressor.com/ while researching a rolling piston compressor. The GRC is described as being similar to a Wankle engine design, but using a "envoluted trochoid". Rolling piston designs are getting significant attention in the literature, the guided rotor compressor I find less on.
Having read some articles online, I was lead to believe that using a very powerful (in HP) compressor and having it operate at a lower capacity than what it's capable of would yield a more favorable energy efficiency (see charts at http://oee.nrcan.gc.ca/industrial/equipment/compressed-air-ref/page-05.cfm?attr=5 ) However, this chart: http://blog.ringpower.com/?tag=/air+compressor seems to state otherwise.
Exactly how is a compression system optimally made ? What type is the best compressor (I assume the one with the best compression ratio) and at what capacity should it operate on (ie 70% ?, 100% ?, less than 70% ?) Also, how is the capacity be calculated (ie does change if you attach another motor, or does the dimensions of the compressor itself dictate a specific power range to the motor ?) How does "flow rate" fit into this (I read that there is an optimal dimension (inlet hole/outlet hole size, ...) depending on the compression ratio you wish to achieve. Finally, does ie a two stage compressor requires 2 compressors (which would be costly); or can a single compressor and two chambers be used instead ?
http://www.locostusa.com/forums/viewtopic.php?f=4&t=4538&start=45 (compression requirements dictating compressor size for optimal effiency ) http://www.grc.nasa.gov/WWW/K-12/airplane/thermo1f.html (--> formula's to calculate optimal design of compressor ?) http://www.grc.nasa.gov/WWW/K-12/airplane/compth.html
- The chart at http://www.sullairinfo.com/industrial/tandem_200804/LIT_TS_TS01E.pdf seems to verify that when using a compressor under capacity, the efficiency is lower; using "variable speed drive" increases efficiency --> does this means using gears or is the RPM of the electric motor simply hightened/lowered ?
- BTW: the images at http://www.sullairinfo.com/industrial/tandem_200804/LIT_TS_TS01E.pdf and http://www.tpub.com/content/NAVFAC/mo206/mo2060037.htm also makes me wonder on the cost/efficiency of using different compressors for each stage (ie a rotary vane compressor could be used for stage 1, followed by a screw compressor for stage 2 or 3). This way, the purchase cost of the devices can be lowered.
- Basically any air compressor or hydraulic pump is below efficiency when underloaded, because the end result is that excess pressure is being vented off through a pressure relief valve.
- Also, if the load working pressure is higher than the actual supplied pressure, energy is wasted getting the pressure way up high, then regulating it back out at a lower pressure. It is much more economical for the system to only provide an output that is sized to match the load required and not much greater.
- The question is more one of "is it better to continuously supply 1000 watts, only use 100 watts, and blow the excess off through a 900 watt resistor bank, ..... or to just supply 100 watts to a 100 watt load?"
- This is not an easy problem to solve for variable or intermittent loads.
"Un-noteworthyness of quasiturbine"
It seems that the quasiturbine for use as a compressor -entry seems to be removed by Andy Dingley. See http://en.wikipedia.org/w/index.php?title=Gas_compressor&oldid=441172211 Given that it's a 80% efficient motor, it should be a very efficient compressor aswell, so simply stating that it's "un-noteworthy" is quite frankly nothing less than an insult to the Saint-Hilaire family. 188.8.131.52 (talk) 16:20, 26 July 2011 (UTC)
Link to in-depth articles
- Why? It's relevant to air conditioning and refrigeration, but not to compressors in general. Andy Dingley (talk) 15:48, 21 October 2012 (UTC)
Normal and standard temperature and pressure
The line saying "Sometimes the capacity of the compressors is written in NM3/hr. Here 'N' stands for normal temperature pressure (20°C and 1 atm ) for example 5500 NM3/hr", is incorrect. The N stands for Normal, meaning standard temperature and pressure, which is at 0°C not 20°C. Anyone doing compressor design can verify this. The websites I list below can also confirm this. http://www.algas.co.id/more-articles/30-general-articles/21-different-between-nm3h-sm3h-and-m3h- http://forum.onlineconversion.com/showthread.php?t=3486 Venny85 (talk) 08:39, 12 January 2013 (UTC)
- I completely removed that sentence for these reasons:
- The sentence was incorrectly and poorly written. NM3 should have been Nm3 and 20°C should have been 0 °C.
- The sentence was completely out of place and out of context.
- mbeychok (talk) 16:39, 12 January 2013 (UTC)
"Heat of compression"
"Heat of compression" is not good terminology. "Temperature rise from compression" is better. Work is done on the gas, changing the state, and the temperature is a property of the new state. This can and is usually done without the addition of heat. After compression, the gas could be isentropically expanded, and work could be produced without heat transfer. In that case, where's the heat? The answer is "there wasn't any to begin with." It's energy. Just sayin'. — Preceding unsigned comment added by 184.108.40.206 (talk) 15:43, 28 May 2015 (UTC)
"Compression of a gas increases its temperature, often referred to as the heat of compression.""
"Adiabatic - This model assumes that no energy (heat) is transferred to or from the gas during the compression, and all supplied work is added to the internal energy of the gas, resulting in increases of temperature and pressure."
As the 2nd quotation correctly asserts, no heat is involved in adiabatic compression, so the phrase "heat of compression" is a misnomer. I have removed it. — Preceding unsigned comment added by 220.127.116.11 (talk) 22:07, 15 March 2015 (UTC)