×
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

Steam compressor enthalpy question.

Steam compressor enthalpy question.

Steam compressor enthalpy question.

(OP)
I've seen a heat exchanger rated for a steam turbine operating at -12 PSIG. According to my tables this corresponds to an steam enthalpy of vaporization of about 1015.5 btu/lbm. yet the enthalpy is listed as 909 BTU/lbm @ turbine outlet.

I'm further confused by the heat load being given 750,000 BTU/HR. I have thought for just condensing the heat load was the mass flow rate times the enthalpy of vaporization. If this is true then the enthalpy based on the heat load is 770 BTU/lbm.

My questions are
1)what reasons would the enthalpy of a dry steam turbine be different from the tabulated value.
2)how do you calculate the heat load (if it is different than mass flow rate times the enthalpy for just condensing of dry steam condesor, or if it is this why would the heat load be different than that value)

Thank You

RE: Steam compressor enthalpy question.

The exit steam is not necessarily at the dry saturated condition. Your conditions of 909 btu/lbm @ 2.7 psia imply a steam quality of about 79%, i.e. 21% of the steam has condensed.

You can download a free turbine steam requirements calculator from my web site.  This program will tell you whether the exit steam is dry or not. See signature below.

Katmar Software
Engineering & Risk Analysis Software
http://katmarsoftware.com

RE: Steam compressor enthalpy question.

(OP)
thanks katmar,

the job was labeled as a 'dry steam condenser', I will double check with the source to make sure tho.

RE: Steam compressor enthalpy question.

(OP)
Katmar, off topic, i checked out your website and your software looks very helpful, but, and no offence, your site is rather dated.

I have a friend that is in college and does websites, she has done quite a few so far, if your interested i can pass on her info. She is very inexpensive and realy just wants to expand her portfolio, and you can check out her work quality.

If not no worries, i thought i'd just through that out there, and thanks again.

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