K-factors for wire mesh screen 1

[bhindle]

I'm trying to find data on the pressure loss coefficient for flow thru wire mesh or perf plate. Everything I have shows the basic K-factors for square edged inlet/outlet, contraction/expansion sections, etc. Nothing on wire mesh or perf. Any suggestions on where to find this information?

 

[codeeng]

Try Koch-Glitsch.

 

[jte]

Not sure if you're dealing with a strainer, but this might help:

http://www.haywardindustrial.com/html/prods/prod.asp?TLDID=1&ProdID=23

jt

 

[Latexman]

My Perry's Chemical Engineers' Handbook (6th Ed.) has a correlation starting on page 5-46.

Good luck,
Latexman

 

[stanier]

Idelchek Fluid Reistance a Design Guide for Engineers

 

[BarryEng]

There is an old publication called 'Low Head Power Plants' by Mosonyi (a fairly thick A5 book).
A formula has been included for trash racks & mesh screens called (I think) Kirshmers formula.
I have used it to calculate head losses for mesh screens (around outlets from reservoirs) & trash racks (in front of intake towers for dam structures), for water utility applications. You will find that the head loss thru screems & trash racks is fairly low for approach velocites of 1 to 2 m/s.
BarryEng

 

[BarryEng]

I found the publication. It is called Water Power Development by Emil Mosonyi, Volume 1 is Low Head Power Plants, 1963.

The formula is on p251 in Chapter 23.

Kirschmer's formula
head loss = (phi(s/b)^^4/3) (v^^2/2g) (sin (alpha))
Where phi = 2.42 for a rectangular bar
= 1.79 for a wire
s = width of rack bars
b = spacing (clearance) between bars
v = velocity of approach (not thru opening)
alpha = angle of bars with the horizontal (trash rack tilted back 30 deg off vertical, alpha is 60 deg)

Perforated plate head loss would just be a sum of head losses thru all of the orifices.

BarryEng

 

[MortenA]

Didnt see this post until now - but this site has a calculator for this value:

http://www.thermal-wizard.com/tmwiz/

Best regards

Morten