×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Mixing refrigerants

Mixing refrigerants

Mixing refrigerants

(OP)
What determines an azeotrope from a blend when two refrigerents are mixed

RE: Mixing refrigerants

It's my belief that the mixture does NOT/will not, separate out at any temperature or pressure. ie. R-502

Regards
pennpoint

RE: Mixing refrigerants

All azeotropes are blends. That is azeotropes are a subset of the universal set of blends. Blends can be zeotropes or azeotropes.

Regards,

RE: Mixing refrigerants

Yeah, what those guys said.

Additionally, the volumetric composition and saturation temperature of zeotropic blends change when used in refrigeration systems, wheras the azeotropic blends do not.  In other words, the components of a zeotropic blend (say R401A which contains R-22, R-152a and R-124) have different vapor pressures and boiling points; so when the fluid evaporates or condenses, the liquid and vapor components will have different compositions.

RE: Mixing refrigerants

for example: Refrigerant R-410A is becoming more common in residential, and commercial units.  More applications will begin using it as the year 2010, R-22 phase-out deadline approaches.  R-410A is a 50-50% blend of 2 refrigerants, it is a non-azeotrope by definition. However,it behaves as a "near-azeotrope" in that the vapor phase change of the two refrigerant components occur so close together, (in temperature and pressure)the refrigeration system performance does not degrade when a bit of lost refrigerant has been replaced. The ratio stays 50-50.  Other blends, such as R-407C have a real system problem when a portion of the refrigerant is lost, as the blend component ratios do not stay equal to the origional since the vapor pressure of each refrigerant component is different. In operation this is refered to as "glide".

More detailed info in a highly readable form is available at

www.qwik.com/R410A/R410A_manual.html

RE: Mixing refrigerants

(OP)
Thanks fellows  for the replys

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources