Pressure drop

[vishalrb]

Hi Sir,

I am trying to calculate pressure drop across perforated plate. has 20 % open area. Hole diameter is 0.25" and plate diamter is 7.33 ft. i have air flow passing through the plate is 1000 SCFM and at 1600 F temperature.

I am also looking for to calculate pressure drop through vartical electric heater . it heats 1000 SCFM air from 80 F to 1600 F . Heater is rectangular in size.

Can anyone help me to find proper formula fot calculate this pressure drop. i know there is online calculators available . but i just dont need anwers also need theory that i can have back up to check. that its right.

Thank you in advance...i really need some help with this.

 

[Latexman]

Did you look in Perry's?

Good luck,
Latexman

 

[MortenA]

D S Miller "Internal flow system" give a curve for loss coefficient vs "free area/total cross sectional area" For sharp and rounded edge perforated plates.

Best regards

Morten

 

[vishalrb]

Thanks you sir,
I have tried to look in perry's but its quite complicated.

 

[Ashereng]

vishalrb,

Please do not multi-post (or do not post the same question in multiple fora. This fragments the thread. If you must, add a link to your primary post in the other fora if you are not getting the answer that you need.

Secondly, "I have tried to look in perry's but its quite complicated."

Is this a school assignment?

"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

 

[davefitz]

I would estimate it the pressure loss as 1.5 velocity heads.
A velocity head is calculated as 0.5 *rho*v^2, whatever units you want to deal with. The velocity is based on 20% of the area of a 7.33 ft dia circle,and air at 1600 F. Go figure.