Questions about static electricity in automobiles

[lostminty]

So,

I don't want to disclose why I want to know about this because its to do with a friends invention and it would be unfair to publish too much information without his consent. That's my disclosure so to speak.

I'm interested in how static electricity is managed in vehicles. I remember cars used to do it a lot, and it seems to happen less now.

I believe it is generated essentially because the car is a common cathode (or anode i never remember convention) and that the fluid flowing over it knocks electrons off/on.

I'm hoping this static energy can be funnelled so to speak so in a particular spot it builds up to a significant level (enough to act as an electrostatic scrubber for waste streams).

 

[lostminty]

I understand it may be far more prudent to just generate the static charge as needed. But thought if there's some already there then it might be enough to be conservative with.

 

[SteamKing]

Static electricity accumulation can be a big problem, especially for gasoline tanker trucks. The tank trailers are equipped with static discharge strips which drag along the road, ensuring that any static electricity has a path to ground.

 

[berkeman]

So,

I don't want to disclose why I want to know about this because its to do with a friends invention and it would be unfair to publish too much information without his consent. That's my disclosure so to speak.

I'm interested in how static electricity is managed in vehicles. I remember cars used to do it a lot, and it seems to happen less now.

I believe it is generated essentially because the car is a common cathode (or anode i never remember convention) and that the fluid flowing over it knocks electrons off/on.

I'm hoping this static energy can be funnelled so to speak so in a particular spot it builds up to a significant level (enough to act as an electrostatic scrubber for waste streams).

I understand it may be far more prudent to just generate the static charge as needed. But thought if there's some already there then it might be enough to be conservative with.

Are you thinking of the static buildup that you get with helicopter rotor blades? It takes a pretty fast airflow to cause static charge separation, I believe. Way more than you have with cars moving through the air.

Or are you thinking of the static charge that you can generate when you slide off of a car seat and out of the car? That's just normal static charge separation, and is mitigated with the material of the seats.

http://scienceblogs.com/sciencepunk/wp-content/blogs.dir/281/files/2012/04/i-b6cd32bbd97348b6c3300ac6b0e5a72f-koppetchells.jpg

 

[berkeman]

Static electricity accumulation can be a big problem, especially for gasoline tanker trucks. The tank trailers are equipped with static discharge strips which drag along the road, ensuring that any static electricity has a path to ground.

Interesting. Is it from the airstream, or something else with the tires?

 

[SteamKing]

I think it comes from the air flow over the tank metal.

Gasoline is also a material which when flowing through the air can also generate dangerous amounts of static electricity. Piping systems to fill storage tanks with gasoline are usually designed so that the gasoline flows into the bottom of the tank without dropping through the air for any appreciable distance, to avoid a buildup of static electricity which might lead to an explosion.

Here is more information about the problem:
http://instrumentsignpost.wordpress.com/2010/11/26/static-earthing-protection-for-road-tankers/

 

[CWatters]

As I understand it it's dust and other particulates in the air rather than air itself that causes static.