Re: [Vo]:Thoughts on the eCat and 130C steam : Pressure drop
At 12:26 PM 9/16/2011, Alan J Fletcher wrote: To maintain an internal pressure of 3 Bar (needed for 130C) you'd need a pretty small orifice : less than 1/32 inch ?. http://www.engineeringtoolbox.com/steam-flow-orifices-d_1158.html (Unfortunately, that's in engineering units .. I'll look for a metric version.) I re-found the metric version for pressure drop in a tube: http://www.engineeringtoolbox.com/steam-pressure-drop-calculator-d_1093.html This is what I used to calculate the pressure drop through the March/April ecat. Suppose the internal pressure is 3 bar, and the eCat is a tube (as in March/April) of about 1 inch diameter Here the flow is 10 kg/hr (assuming all gas) -- so the pressure drop would be 1 kPa (1 Bar) per 100m -- or only 3/100 = 0.03 Bar for 3 meters. I'm still looking for the 'orifice' needed to create 3 Bar internal pressure.
Re: [Vo]:Thoughts on the eCat and 130C steam : Pressure drop
Am 16.09.2011 22:13, schrieb Alan J Fletcher: At 12:26 PM 9/16/2011, Alan J Fletcher wrote: To maintain an internal pressure of 3 Bar (needed for 130C) you'd need a pretty small orifice : less than 1/32 inch ?. http://www.engineeringtoolbox.com/steam-flow-orifices-d_1158.html (Unfortunately, that's in engineering units .. I'll look for a metric version.) I re-found the metric version for pressure drop in a tube: http://www.engineeringtoolbox.com/steam-pressure-drop-calculator-d_1093.html This is what I used to calculate the pressure drop through the March/April ecat. Suppose the internal pressure is 3 bar, and the eCat is a tube (as in March/April) of about 1 inch diameter Here the flow is 10 kg/hr (assuming all gas) -- so the pressure drop would be 1 kPa (1 Bar) per 100m -- or only 3/100 = 0.03 Bar for 3 meters. I'm still looking for the 'orifice' needed to create 3 Bar internal pressure. The previous versions all had a pressure relief valve. It could be that he (ab)used the pressure relief valve for the demonstration to generate some overpressure, but he dont want to tell us. Possibly he will not create overpressure in the 1MW system. We dont know. Only Rossi knows. So if you have the guts and go into this big 1 MW box under full operation then your health and live is subject to god's grace and Rossis skills if something unexpected happens. I would not go inside after having seen the video Peter
Re: [Vo]:Thoughts on the eCat and 130C steam : Pressure drop
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
Re: [Vo]:Thoughts on the eCat and 130C steam : Pressure drop
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.
