Am 16.09.2011 23:25, schrieb Alan J Fletcher:
At 01:13 PM 9/16/2011, Alan J Fletcher wrote:
I'm still looking for the 'orifice' needed to create 3 Bar internal
pressure.
Napier's formula (accurate to about 3%) for steam going through an
orifice in a flat plate, to atmospheric pressure.
W = p * a / 70
Where W is flow lbs/sec
p is pressure lbs/in^2
a is area inches^2
or in reverse
a = W * 70 / p
p = W * 70 / a
To get a 3 Bar drop at 11 kg/hr I calculate the radius as 0.15 cm.
If we say half of that is water, (steam flow 5.5 kg/hr) we get 0.1 cm
What's the estimated radius of the short length of outlet hose ... 0.5
cm ?
The pressure drop at 5.5kg/hr through 0.5 cm radius is only 0.13 bar
You can here find industrial diagrams that avoid a lot of calculations:
Loss of pressure in pipes:
http://www.dampferzeuger.de/userFiles/de/Blatt-Druckverluste-270509.pdf
Recommended or standadized pipe crossectional area for steam:
http://www.dampferzeuger.de/userFiles/de/Blatt-Dampfleitung-270509.pdf
Tables for data of saturated steam:
http://www.dampferzeuger.de/userFiles/de/Blatt-Sattdampfdaten-280509.pdf
Unfortunately it is in german, but if you look to the measuring units it
should become understandable.