Air compression values

[terravent]

This may appear to be a silly question, but I would like to know what pressure would be be achieved if you were to compress, in one stroke, a cylinder with a volume of 1 litre, containing 1 litre of air at atmospheric pressure. The stroke value or movement will reduce the cylinder volume by 50% to 0.5 litre.
Thank you in anticipation.

 

[israelkk]

2 atm

 

[quark]

2 incase of isothermal(if the process is slow) and 2.639 if it is adiabatic(if the process is fast)

 

[gbmax]

Hello everyone,
this is my first time with any group such as "eng-tips" so I hope I'm using the correct procedure.

I'm trying to find out how to calculate the diameter and legth of the piston rod for a reciprocating gas compressor (natural gas) with the following statistics.
Stroke 300mm
inlet pressure 52.00 BARA
discharge pressure 240 BARA
Speed 350 RPM
Flow Rate 19,000 Nm/hr
Power 1400 kW

 

[zdas04]

GBMax,
You really should start a new thread with a new question. You can copy and paste from the above into a new thread with a new name.

Changing topics within a thread is seldom a good idea since it makes manual searches impossible (and many automated searches will be skipped since the title of the thread doesn't match your question).

David

David Simpson, PE
MuleShoe Engineering

http://www.muleshoe-eng.com

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

The harder I work, the luckier I seem

 

[Montemayor]

Max:

Firstly, since this is your first time on this Forum, you are not using the correct procedure. This thread was started by terravent for another totally different topic and it belongs to him/her. You should start your own thread, specifically for the purpose you outline.

I can easily show you how to calculate the diameter of a required compressor piston for a reciprocating compressor. I can’t calculate the “legth” (sic) or length of the piston rod – and neither can anyone else. The length of the piston rod is determined by the compressor manufacturer and is independent of the gas-end calculations. It is dependent on the mechanical work, type of design, and the forces imposed on the machine.

What you have to give us is the inlet gas flowrate at the suction temperature and pressure, the stroke of the piston, the strokes per minute (or rpm), the volumetric efficiency of the cylinder, single-acting or double-acting, and the piston rod diameter if double-acting. You state that you have 19,000 Nm/hr of natural gas, but you don’t identify what you mean by “normal”. Do you mean Nm3/hr as measured at 0 oC & 1 atmosphere? There are at least three conventions in common use.



I’ll look forward to your posting.