I have been trying to understand the unusual behavior of the ECAT water input
pump. It appears that the same pump was used in both of the recent
demonstrations. Mats Lewan made excellent notes during his September test that
accurately measured the pump output at several points in time. The video he
produced allows me to readily determine that the pump cycle rate is set to 50
pulses per minute. The total water flow into the ECAT should be 2 grams per
cycle x 50 cycles per minute which equals 100 grams per minute. This
translates into 6 kilograms per hour or 1.66666 grams per second.
He actually measured a different value. His unloaded calibration check showed
that 15.8 kilograms per hour (4.388888 grams per second) were delivered into
his measuring device. He proceeded to measure a flow rate of 13.76 kilograms
per hour (3.82222 grams per second) during an accurate measurement of the water
used up from his input container until boiling was achieved per his document
(100 degrees centigrade). An additional measurement of water consumed from the
boiling point to the test completion showed a usage of 11.08 kilograms per hour
(3.07777 grams per second). None of the three measurements came close to the
expected value based upon the rate setting. The only measurement that suggests
reasonable expectation is the fact that the maximum pump flow rate is specified
as 12.0 liters per hour or 3.33333 grams per second. This should be delivered
into a pressure of 1.5 bars by specification.
Mr. Rossi has stated that the water flow rate into the ECAT is 15.0 kilograms
per hour during his testing. It appears that the pump is not capable of any
more than 11.08 kilograms per hour when subjected to the operational pressures
within a heated ECAT. It is important to have a reasonable estimate of the
water flow into the unit for me to be able to get an accurate level calculation.
Has anyone seen a reason for the difficulty in my ability to calculate the pump
performance? Does the vortex have members with one of these pumps in their
possession and experience with its operational characteristics? Any
suggestions would be appreciated.
We have used a value of 1.5 grams per second for the flow rate within our
calculations related to the recent test on October 6, 2011. I do not feel like
this is an accurate number to use at this point due to the above reasons. My
plan is to modify the Excel program that I have constructed to reflect an input
water flow rate that is closer related to the measurements made by Mats during
September unless I can determine my error.
It appears that the actual pump stroke capacity is approximately 4.58666 grams
until the internal water temperature exceeds 100 degrees centigrade. I obtain
a flow rate of 3.06 grams per second at the latest pump pulse rate of 40 pulses
per second for October 6 related calculations. Some type of curve fitting
procedure will be used to estimate the pump flow rate roll off at temperatures
above 100.
Dave
