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I do not think that claim has any merit at all.
I do not know what the internals of the pump in question look like, but let's consider a simpler case and what it might mean.
Suppose we have an insulated wire in seawater that has DC current running through it. This claim would presumably suggest that the outside of the wire will somehow get fouled faster than the same wire without current running through it.
We will ignore the potential for the wire to heat up as current flows through it. Any temperature increase will tend to increase the likelihood of precipitation of calcium carbonate. That is why pumps get fouled to begin with. But it does not relate to DC vs AC.
There is little, if any, electric field extending outside of an insulted wire that is carrying current. Physicists and electrical engineers like to debate this subject, as some brief googling turns up, and the theories get very complicated. If it was substantial, a simple measurement would answer the question for them. lol
Let's assume for fun that there is a simple electric field (a net charge) on the surface of the wire. What would that do to the chemistry at the surface?
It is very well known what happens to ions near a surface with an electric charge. There is a slight excess of ions with the opposite charge and a slight deficit of ions with the same charge. This effect only extends a few water molecules distance from the surface, so it is extremely localized.
Suppose the wire has a net negative charge on it. Calcium (and sodium, magnesium, potassium, etc.) will all tend to have a very slightly higher concentration near it. Carbonate (and bicarbonate, chloride, sulfate, etc.) will all tend to have a very slightly lower concentration near it.
Is the supersaturation of calcium carbonate changed in a way that would induce precipitation? No.
The supersaturation of calcium carbonate is the concentration of calcium times the concentration of carbonate. Since calcium and carbonate carry the same but opposite charges (+2 and -2), they will experience the same (but opposite) effects on concentration due to the electric field. Thus one will rise, the other fall, and supersaturation will stay exactly the same.
Hence I conclude that the wire is not more prone to fouling with calcium carbonate even if it has a net charge extending from it.
I will also note that an AC wire will do everything a DC wire does for the time that the current is flowing in one direction, and for 60 HZ current, that is plenty long enough for the ions to move around in response to the electric field. Thus an AC-carrying wire will also experience these sorts of ion concentration changes.
FWIW, I'm also ignoring the magnetic field issues since I do not think there is any convincing evidence that magnetitic fields will induce the precipitation of chemicals onto the wire unless they are magnetic materials to begin with. Both AC and DC currents produce magnetic fields This web site discusses magnetic fields around current-carrying wires:
Magnetism and Magnetic Fields | Boundless Physics
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YesI do not think that claim has any merit at all.
I do not know what the internals of the pump in question look like, but let's consider a simpler case and what it might mean.
Suppose we have an insulated wire in seawater that has DC current running through it. This claim would presumably suggest that the outside of the wire will somehow get fouled faster than the same wire without current running through it.
We will ignore the potential for the wire to heat up as current flows through it. Any temperature increase will tend to increase the likelihood of precipitation of calcium carbonate. That is why pumps get fouled to begin with. But it does not relate to DC vs AC.
There is little, if any, electric field extending outside of an insulted wire that is carrying current. Physicists and electrical engineers like to debate this subject, as some brief googling turns up, and the theories get very complicated. If it was substantial, a simple measurement would answer the question for them. lol
Let's assume for fun that there is a simple electric field (a net charge) on the surface of the wire. What would that do to the chemistry at the surface?
It is very well known what happens to ions near a surface with an electric charge. There is a slight excess of ions with the opposite charge and a slight deficit of ions with the same charge. This effect only extends a few water molecules distance from the surface, so it is extremely localized.
Suppose the wire has a net negative charge on it. Calcium (and sodium, magnesium, potassium, etc.) will all tend to have a very slightly higher concentration near it. Carbonate (and bicarbonate, chloride, sulfate, etc.) will all tend to have a very slightly lower concentration near it.
Is the supersaturation of calcium carbonate changed in a way that would induce precipitation? No.
The supersaturation of calcium carbonate is the concentration of calcium times the concentration of carbonate. Since calcium and carbonate carry the same but opposite charges (+2 and -2), they will experience the same (but opposite) effects on concentration due to the electric field. Thus one will rise, the other fall, and supersaturation will stay exactly the same.
Hence I conclude that the wire is not more prone to fouling with calcium carbonate even if it has a net charge extending from it.
I will also note that an AC wire will do everything a DC wire does for the time that the current is flowing in one direction, and for 60 HZ current, that is plenty long enough for the ions to move around in response to the electric field. Thus an AC-carrying wire will also experience these sorts of ion concentration changes.
FWIW, I'm also ignoring the magnetic field issues since I do not think there is any convincing evidence that magnetitic fields will induce the precipitation of chemicals onto the wire unless they are magnetic materials to begin with. Both AC and DC currents produce magnetic fields This web site discusses magnetic fields around current-carrying wires:
Magnetism and Magnetic Fields | Boundless Physics
Study Guides for thousands of courses. Instant access to better grades!
YesI do not think that claim has any merit at all.
I do not know what the internals of the pump in question look like, but let's consider a simpler case and what it might mean.
Suppose we have an insulated wire in seawater that has DC current running through it. This claim would presumably suggest that the outside of the wire will somehow get fouled faster than the same wire without current running through it.
We will ignore the potential for the wire to heat up as current flows through it. Any temperature increase will tend to increase the likelihood of precipitation of calcium carbonate. That is why pumps get fouled to begin with. But it does not relate to DC vs AC.
There is little, if any, electric field extending outside of an insulted wire that is carrying current. Physicists and electrical engineers like to debate this subject, as some brief googling turns up, and the theories get very complicated. If it was substantial, a simple measurement would answer the question for them. lol
Let's assume for fun that there is a simple electric field (a net charge) on the surface of the wire. What would that do to the chemistry at the surface?
It is very well known what happens to ions near a surface with an electric charge. There is a slight excess of ions with the opposite charge and a slight deficit of ions with the same charge. This effect only extends a few water molecules distance from the surface, so it is extremely localized.
Suppose the wire has a net negative charge on it. Calcium (and sodium, magnesium, potassium, etc.) will all tend to have a very slightly higher concentration near it. Carbonate (and bicarbonate, chloride, sulfate, etc.) will all tend to have a very slightly lower concentration near it.
Is the supersaturation of calcium carbonate changed in a way that would induce precipitation? No.
The supersaturation of calcium carbonate is the concentration of calcium times the concentration of carbonate. Since calcium and carbonate carry the same but opposite charges (+2 and -2), they will experience the same (but opposite) effects on concentration due to the electric field. Thus one will rise, the other fall, and supersaturation will stay exactly the same.
Hence I conclude that the wire is not more prone to fouling with calcium carbonate even if it has a net charge extending from it.
I will also note that an AC wire will do everything a DC wire does for the time that the current is flowing in one direction, and for 60 HZ current, that is plenty long enough for the ions to move around in response to the electric field. Thus an AC-carrying wire will also experience these sorts of ion concentration changes.
FWIW, I'm also ignoring the magnetic field issues since I do not think there is any convincing evidence that magnetitic fields will induce the precipitation of chemicals onto the wire unless they are magnetic materials to begin with. Both AC and DC currents produce magnetic fields This web site discusses magnetic fields around current-carrying wires:
Magnetism and Magnetic Fields | Boundless Physics
Study Guides for thousands of courses. Instant access to better grades!
