Talk:Compression ratio

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Should this information be in a seperate article, or in an article on internal combustion engines? I ask this for two reasons:

  1. The term is also used in data compression, but more importantly...
  2. It doesn't seem a topic that is self-contained enough to warrant a full-blown article.

Repy: I found it to be very helpful the way it is. 192.75.238.205 21:53, 18 May 2006 (UTC) JT

Contents

[edit] First sentence

I replaced this:

"The mixture of fuel and air is a single number that can be used to predict the performance of any internal-combustion engine."

with this:

"The compression ratio is a single number that can be used to predict the performance of any internal-combustion engine."

Since that is what the sentence is trying to say, and, also, wikipedia style says that the title should be the subject of the first sentence of an article.

-- human 16:03, 26 June 2006 (UTC)

[edit] Natural gas

"I am a manufacture of high pressure cng (compressed natural gas) compressors and cng engines and vehicles and there is an error in your statement concerning the compression ratio natural gas engines can operate on. They in fact can operate in the diesel range above 14 to 1 without pre-detonation (knock)."

This comment was in the article itself, I am moving it here so someone can verify, etc., and perhaps turn it into a useful statement somewhere in the article.

-- human 16:49, 26 June 2006 (UTC)

[edit] Clean up

I have removed the 'clean up' tag. Has anyone any objections to this? - Ballista 07:34, 1 August 2006 (UTC)

[edit] Error in formula

The formula should be either

\mbox{CR} = \frac { (\pi b^2 s) / 4 + V_c } {V_c} OR \mbox{CR} = \frac { \pi (.5b)^2 s + V_c } {V_c}

and not

\mbox{CR} = \frac { (\pi (.5b)^2 s) / 4 + V_c } {V_c}

-- ElroyH 18:25, 4 October 2006 (UTC)

[edit] Error in formula... still.

The volume of a cylinder is the area of the top of the cylinder times the height of the cylinder if the circle on top is the same area as the circle on the bottom. That formula for the volume of a circle is (pi)*(radius^2). For a cylinder you just multiply the area by the height. (pi)*(radius^2)*(h). The bore size is the diameter, not the radius. The radius is half of the bore. Square it! To apply this to a internal combustion cylinder you must change the height to stroke length add the additional volume of the head's combustion area. So a formula should look like so:

{(pi)*[(.5*bore)^2]*stroke}+(volume of head)

Basically the only thing I am changing is that the bore is in diameter and not in radius. If you would half the bore and then square it you would get the correct answer you are looking for.

[edit] Gas

Which is gas with the best compression ration at room temperature ? (this is, uses less space to be stored).--Mac (talk) 17:16, 27 January 2008 (UTC)