Contact US

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!

*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

Temperature Variation of N2 Gas in a accumulator?

Temperature Variation of N2 Gas in a accumulator?

Temperature Variation of N2 Gas in a accumulator?

I am trying to calculate the variation of temperature of N2 in the accumulator because of the variation in ambient temperature. When the ambient temperature varies a lot, the pressure of N2 also varies accordingly to gas laws. The idea now is to find out what is the time taken for the N2 gas to either increase of decrease in temperature because of the variation of ambient temperature with and without the use of an thermal insulation.

The way I have formulated this problem can be found in the attachment. Initially I formulated the transient heat transfer equation for the barrier fluid in the accumulator and then it is used to calculate the temperature of the gas. Can anyone have a check and put your comments to understand if this approximation is good enough or not. Thanks for your support in advance. If there any additional info required, please advise.

RE: Temperature Variation of N2 Gas in a accumulator?

Your final equation appears consistent with some of my past work on other projects, so I would say that you are on the right track. What may be missing is the heat retention of the accumulator unless it is considered a thin wall accumulator. As far as the heat transfer within the N2 gas, you have based it on convection but if the accumulator of not a big system, perhaps consider conduction within the N2 gas instead of convection. There will also be heat transfer loss from the accumulator to ambient surroundings which I did not see included.

RE: Temperature Variation of N2 Gas in a accumulator?

Heat transfer thru conduction is to be considered if there is no movement of the gas N2 inside the accumulator.

RE: Temperature Variation of N2 Gas in a accumulator?

That movement of the N2 gas inside the accumulator depends on the cycle frequency and cycle volume (amount of N2 moving each time the accumulator moves). If the combination of the two is small, it won't matter. Local gas at ambient temp is cycled in and out of the accum - also at ambient temp, and the work of compressing and releasing is small.

RE: Temperature Variation of N2 Gas in a accumulator?

I'll confess I didn't follow the entire path through that set of calculations, but I'm still wondering why you're bothering to find out.

The pressure variation would appear to be about 30K / 280K so a bit more than 10%??

I would normally try and control the pressure directly.

I also think you have too many variables and assumptions to make to get a decent answer in theory as opposed to just testing it.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

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! Already a Member? Login


Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close