Why Care about Antibubbles?

Some readers may think that antibubbles have no practical significance -- that they are just a childish waste of time. I suppose those readers have more important things to worry about. Not me. I know antibubbles are important. If nothing else, they prove that even the simplest things may suprise us. Antibubbles give me hope. I like things to suprise me

But plant engineers don't like suprises.

In the controlled nuclear reactions that occur in nuclear reactors and in controlled large-scale exothermic chemical processes, cooling water is carefully monitored. In some of these systems, "bubble counting" equipment is used to count bubbles flowing through the cooling pipes. An optical X-Y sensor grid is used to detect, measure, and count bubbles passing a certain point. From this data a "void fraction" of the cooling water can be calculated. Void fraction basically specifies how much air is in the water and how much it's cooling capacity has been degraded by its presence. Process control parameters and cooling water flow is modified to account for void fraction.

Now consider this: if the bubbles detected are actually antibubbles, the void fraction will be dramatically overestimated. This may have adverse effects on the process control system. In extreme cases, the control system could oscillate, doing catastrophic damage to the plant, or worse.


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