To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.technicOpen lugnet.technic in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Technic / 12728
12727  |  12729
Subject: 
Re: SSClagorpion - Compressor
Newsgroups: 
lugnet.technic
Date: 
Wed, 2 Jun 2004 20:28:42 GMT
Viewed: 
19579 times
  
In lugnet.technic, Steve Hassenplug wrote:
In lugnet.technic, Steve Hassenplug wrote:

So, my general assertion is that the "work" required to compress six small pumps
is the same as the work required to compress one large pump.  That should take
into account the "pushback" pressure.


Ok, so my co-worker (with a degree in physics) said (after many calculations)
that the Work is directly related to the Volume.

Assuming 6 small pistons pump the same volume as 1 large piston, it will take
the same amount of work.

Keep in mind, with 1 piston, half the time you are doing no work, and half the
time you are doing a bunch of work.  So, you should test 2 large vs 12 small.

One thing not represented in your calculations is time.

Compressing one large pump takes more force than it takes to compress one small pump.  With six small pumps seperated by 60 degress of phase.   We can compress/expand six small pumps in the time it takes to compress one large pump.  So at any given point in time, we're only ever compressing 3 of the six small pumps.

This means that we're only compressing three of the faces at a time and
therefore the peak force required in the small pump compressor is less.  This
means that a given motor and its maximum torque capabilities should be able to
drive the pressure higher, because the peak torque requirement is lower.

Fun discussion!

This gives me insight into comparisons of large pump compressors vs small pump
compressors.  Those of us who have been in the large pump superiority camp (I
was one of them), probably have never made a fair comparison to the appropriatly
sized small pump compressor.  If you don't compare a small six against a large
one with the same motor, you are not comparing apples to apples (unless you make
sure to run the small pump six times as fast....)

Kevin



Message has 1 Reply:
  Re: SSClagorpion - Compressor
 
(...) ... (...) That's what I was trying to say above. Sometimes, I think faster than I type, so all the details don't make it to my fingers... Yes, adding pistons at various angles will help even out the "work" required. So, 2 large pistions at 180 (...) (20 years ago, 2-Jun-04, to lugnet.technic)

Message is in Reply To:
  Re: SSClagorpion - Compressor
 
(...) Ok, so my co-worker (with a degree in physics) said (after many calculations) that the Work is directly related to the Volume. Assuming 6 small pistons pump the same volume as 1 large piston, it will take the same amount of work. Keep in mind, (...) (20 years ago, 2-Jun-04, to lugnet.technic)

300 Messages in This Thread:
(Inline display suppressed due to large size. Click Dots below to view.)
Entire Thread on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact

This Message and its Replies on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

Custom Search

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR