Tuning intake / outlet pipes on recips
Tuning intake / outlet pipes on recips
(OP)
Not my field, forgive me if this is dumb, but I did search first and didn't find anything with "tuned" or "tuning".
On automotive engines, tuning intake and exhaust plumbing makes a measurable MPG difference. I would assume that for new reciprocating compressor designs modern tuning is being applied. Anybody here know anything about tuning the headers for old, medium-to-large reciprocating compressors?
Any experience to support or contradict the idea that it would improve efficiency?
How do you measure the extent to which the existing tubing is mis-tuned?
XLEs delivering plant air are my immediate focus.
Thanks!
On automotive engines, tuning intake and exhaust plumbing makes a measurable MPG difference. I would assume that for new reciprocating compressor designs modern tuning is being applied. Anybody here know anything about tuning the headers for old, medium-to-large reciprocating compressors?
Any experience to support or contradict the idea that it would improve efficiency?
How do you measure the extent to which the existing tubing is mis-tuned?
XLEs delivering plant air are my immediate focus.
Thanks!





RE: Tuning intake / outlet pipes on recips
I don't have the vaguest idea of what you mean to do with the suction and discharge of a reciprocating compressor by "tuning" it. Are you refering to pressure drop? Are you refering to torsional analysis? Are you refering to vibrational analysis? Those I've done or had done on recips. "Tuning" is something I've never heard of with regards to recips. I've never seen or read it anywhere.
Perhaps if you define what you mean by "tuning", "headers", "medium-to-large", "tubing", I could learn something after 46 years. The terms you use are related to internal combustion engines and not reciprocating compressors. Maybe you are refering to an engine driver for a reciprocating compressor and I'm missing the point. Also, which efficiency are you refering to?
RE: Tuning intake / outlet pipes on recips
Strong pulsation in a recip compressor can have significant effect both on efficiency as well as compressor valve life.
There are a number of digital simulation programs for doing this kind of analysis on a new machine. In addition it is not unusual on an existing installation to use dynamic pressure transducers to measure the cylinder PV curve and compare it with predicted to determine if pulsation effects are causing a compressor efficiency loss.
-The future's so bright I gotta wear shades!
RE: Tuning intake / outlet pipes on recips
-The future's so bright I gotta wear shades!
RE: Tuning intake / outlet pipes on recips
Again, I'm not a mechanical engineer so this is a cartoon level appreciation, but it is my understanding that in reciprocating internal combustion engines they actually design the "pulsation control" to provide a standing acoustic wave with pressure peaks synchronized with intake valve opening and conversely with the negative pressure peaks at the exhaust valves.
Energy balance works because you are using waste acoustic energy to replace some of the suction to drive air through the intake valve.
Montemayor, my question was based on reasoning by analogy between IC engines and recip compressors. Apparently the considerations are not as similar as I had naively expected.
Perhaps the IC engine efficiencies are more sensitive to effective intake air density than compressors are? Total air delivery might be improved slightly but not energy efficiency for the compressor case?
RE: Tuning intake / outlet pipes on recips
-The future's so bright I gotta wear shades!
RE: Tuning intake / outlet pipes on recips
Tuning as defined by you is not done on reciprocating compressors. One of the reasons is that recip. compressors work with vairable compression ratios as opposed to engines which have a fixed compression ratio. Though theoretically it may be possible to charge the compressor to a higher suction pressure and thus improve the through-put nobody does it in practice because of above reason.
Another reason is the type of valves used in recip compressors. These valves are not timed and are pressure actuated. They have a much more complicated dynamics compared to engine valves which are camshaft driven.
Gurmeet
RE: Tuning intake / outlet pipes on recips
See: Perdue university, I forget the rest and as the whole office is being moved I dont have any references handy.
(I know you can find this through their website however.)
RE: Tuning intake / outlet pipes on recips
RE: Tuning intake / outlet pipes on recips
"Tuning" simply means adjusting the lengths of piping such that they are placed off resonance. For machines that run at a fixed speed, this is easy. For high speed/variable speed machines, it becomes difficult/impossible, and pressure drop (i.e., orifice plates) must be used for pulsation control.
In the case of a car engine, there is lots of hype regarding tuning, and from what I can tell, it is just hype.
RE: Tuning intake / outlet pipes on recips
-The future's so bright I gotta wear shades!