×
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

Noise level & distance issue

Noise level & distance issue

Noise level & distance issue

(OP)
Hello everybody,

hope all is fine !
I looked in old post but I have not found similar topics.

Please, I'd like to ask you some help since I am stuck in an issue that is puzzling me !

I am facing in following topic: I have a Sound pressure level declared at a certain distance of a long dimension of a unit and @3 m from the ground, according to an hemispherical surface. No reference standard is quoted.

The unit is a sort of parallelepiped with a ratio long/width 6: 1

What makes me confused is what follows:

1 - according to sound theory in case of hemisphere I shall consider the unit as a point, therefore why considering distance from the long dimension ?
2 - which is the influence of the ground distance ? According to theory the ground is in any case a surface that reflects energy

Hope somebody can help me

Thanks in advance !
 

RE: Noise level & distance issue

(OP)
Many thanks.

As a matter of fact I cannot find any reference standard as per my introduction.

Would you be so kind and quoting this standard ?

Many thanks

RE: Noise level & distance issue

Sorry, I just know it a sthe MIRA method, as opposed to the hemispherical one which is an ISO.

The distance from the ground has an enormous effect on narrowband noise due to cancellation and reinforcement. Are you in an open field, a semi anechoic chamber, or a reverberant room?

Hopefully not the latter.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies  http://eng-tips.com/market.cfm?

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