In the tradition of Alan Fletcher's exemplary skepticism: If the pressure at the output thermocouple of the Oct 28 demo exceeds the critical pressure of steam at the reported temperature, then there is no heat of vaporization represented in the mass flow hence in the imputed power level.
We may give Rossi the benefit of the doubt (doubt created in his response to me wherein he said that the pressure at that thermocouple never exceeded "20mm water column") and presume he merely poorly expressed his answer or poorly understood my question (which was repeated later by another person). 20mm water column would most definitely not have been sufficient to drive the fluid flow from that thermocouple, to the condensers, through the condensers and then, as liquid water, back along the ground and then up to the level of the water in the holding tank. The question then becomes: What is the plausible range of pressures at the thermocouple to sustain that flow? If the lower range of those plausible pressures exceeds the critical pressure reported at the thermocouple, then it throws the entire test into serious doubt. Rather than rhetoric, here's some arithmetic: The pressure drop in saturated steam distribution pipes can be calculated in metric units as<http://www.engineeringtoolbox.com/steam-pressure-drop-calculator-d_1093.html> *dp = 0.6753 106 q2 l (1 + 91.4/d) / ρ d5 * *where * *dp = pressure drop (Pa)* *q = steam flow rate (kg/h)* *l = length of pipe (m)* *d = pipe inside diameter<http://www.engineeringtoolbox.com/asme-steel-pipes-sizes-d_42.html>(mm) * *ρ = steam density<http://www.engineeringtoolbox.com/saturated-steam-properties-d_457.html>(kg/m 3)* Examination of the videos of the steam pipe between the thermocouple and the condenser, and estimating values that will minimize the pressure drop, I would estimate the diameter to be 200mm over a length of 2 meters, followed by a narrowing (over a short distance) down to 100mm, then distributing out to 7 condensing channels, each about 2cm in diameter having a total length (cross and back) of 2 meters, then feeding back about 4 meters along the ground as liquid water through a pipe that's about 100mm, and then rising to the water level of the holding tank, at around 700mm height. So the above equation has to be applied in 2 places: 1. steam to condenser and 2. through one leg of the round trip through a condenser channel (presuming it is gas phase only half way through the condenser channel) The narrowing down from 200mm to 100mm would involve a pressure drop as well, but that may be dominated by the immediate distribution to the condenser's channels. Then, on the return trip, we're dealing with liquid phase water, the head loss due to flow is given by: Summarized Major Losses<http://www.engineeringtoolbox.com/total-pressure-loss-ducts-pipes-d_625.html> The major head loss<http://www.engineeringtoolbox.com/major-loss-ducts-tubes-d_459.html>for a single pipe or duct can be expressed as: *hmajor_loss =λ (l / dh) (v2 / 2 g)** (2)* *where* *hloss** = head loss (m, ft)* *λ** = friction coefficient* *l** = length of duct or pipe (m)* *dh** = hydraulic diameter<http://www.engineeringtoolbox.com/hydraulic-equivalent-diameter-d_458.html>(m) * *v** = flow velocity (m/s, ft/s)* *g** = acceleration of gravity<http://www.engineeringtoolbox.com/accelaration-gravity-d_340.html>(m/s 2, ft/s2)* This would, again, apply twice: 1. To the return leg of the condenser channel (one of 7) 2. To the water pipe running along the ground to the holding tank. This doesn't take into account the head loss from rise from ground level to the water level in the holding tank. So a couple of questions: 1. Is this an adequate set up of the problem -- presuming we are attempting to identify the minimum plausible pressure at the output thermocouple? 2. Examining the condenser itself, the condenser channels are horizontal pipes in a vertical array, so the steam feeder and water collector pipes must be vertical. But this creates a problem on the water collection side: What is the water level and how is it to not interfere with the entry of steam at that level?
