×
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

Flow increase requirements when Glyocol is added

Flow increase requirements when Glyocol is added

Flow increase requirements when Glyocol is added

(OP)
As we know, as the % of glycol is added to a system, more flow is required for the same amount of btu's. I have a  small program that is capable of this, but it is not windows friendly and I have come across a situation that makes me suspect the program has a flaw. I use Excel extensively for estimateing and for shop dwgs and valve sizing etc. Does someone have a precise formula for the required increase in flow for varying glycol concentrations. To go one further, does someone have a formula that will allow you to enter the required BTU's, Water Temp in, Water Temp out, and glycol concentration thus calculate the required GPM of fluid?

RE: Flow increase requirements when Glyocol is added

The relation is about the especific heat from water to water+glicol.
Maybe you need to search about this value.

Heat = massflow x Specific heat x (T in - T out)


Pardal

RE: Flow increase requirements when Glyocol is added

Flow in GPM = Cap in TR x 12000 / (500 (Sp heat) x Delta T)

This is for water.  The only variable between water and glycol would be the factor of 500 - i.e. Sp heat.  If you were to add glycol, this factor would be change to less than 500, say 425 or 435 depending on the concentration of glycol that you are adding.

There must be a table giving these values.  I can't lay my hands on it immediately.  But, can find out, time permitting.

Sriram

RE: Flow increase requirements when Glyocol is added

The best source for this information is a manufacturer or supplier of water treatment products.  There are many variations on the standard glycol product.

I have a chart that shows changes in pressure drop, flow rate and capacity, against the % of ethylene glycol.  If you want a copy, post your fax number (including the international dialling code when dialling from the UK).

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