Here is the Challenge: Without introducing a completely different measurement method, such as differential pressure through an orifice, $$$ mass flow meter, etc. how can existing setup be improved to allow less corrections for changes in liquid level during water displacement, and at the same time re-design #1 bubbler (also the condensate receiver vessel) such that condensate will drain off to another vessel using a convenient overflow tube.
Final receiver vessel will have means of at least manually discharging the accumulated condensate periodically, while still under pressure (not more than approximately 35" H2O head) to condensate pump supply vessel (coffee can). I envision a clear PVC pipe with caps at top and bottom, a plate divider in the middle, the overflow hook tube (inverted asymmetric U) passing through the plate, and a pressure equalizing tube passing through with openings of this tube in the upper and lower head spaces of the new revised #1 bubbler.
Would it be easier (perhaps) to suspend the collector jar (from load cell) instead of resting on balance pan, to reduce displacement height?
Existing Setup:
1. You are presented with a gas evolution flow from an electrolysis experiment where gas flow is more or less proportional to current between the electrodes.
2. The gas is bubbled through a cylindrical vessel, #1 bubbler, then proceeds to another jar, #2 bubbler, where the gas bubbles at the bottom, then forces water out through a tube in the bottom to a collecting jar resting on a load cell. the load cell records mass over time, and processor calculates flow rate once per measurement cycle. measurement cycle can be set from one second up to 60 seconds, or more, depending on the buffoon programming it. #1 bubbler is about 0.75 L volume, with about 30% free board most of the time. #2 bubbler is a 1.5 L vessel with lid on it having ports and fittings, sealed, etc. Level in #2 changes as water moves and is weighed.
3. It has been observed from the data log, that apparent flow rate varies downward (after a stall sequence at the beginning where the bubble jars pressurize slightly) over a number (about ten or so) measurement cycles, until #2 bubbler is nearly empty, and the collector jar is nearly full (and scale reads 0.600 Kg.) at which point a dodgy solenoid valve opens and dumps gas pressure, allowing the collector jar to siphon back to the bubbler #2. Measurement cycles then re-initialize, while data log remains active on the same file (to conserve file names).
4. Variation in pressure from start of major cycle to 0.600 Kg point is considered to be the measurement of meniscus in #2 bubbler to the top of the delivery tube to collector jar (atmospheric pressure in collector jar). Variation range: 25" H2O increasing to 28" H2O. Obviously, with higher gas flow rates there will be changes in dynamic pressure due to tube impedance, but this is constant during each set of measurements prior to the "dump".
5. The gas coming from the reactor includes whatever water vapor from the warm to hot reactor (within 10 C of boiling at times). We are going to introduce an air-cooled condenser to dry out the gas stream to hold minimal water. All condensate formed will, unfortunately be carried in the gas tube to #1 bubbler.
Picture of the existing set-up: Pending (will be sent tomorrow if possible).
Design Challenge of the Month, Year, or Whatever
Re: Design Challenge of the Month, Year, or Whatever
"Almost" Good Answers: