Basic electricity problem...

[highendtron]

I have a friend that wants to vaporize gas for better gas mileage. He wants to use a 12 volt car system to drive 4 glow plugs. The glow plugs will run indefinitely using 6 volts and can only handle short bursts using 12 volts. Each glow plug draws 11 amps. We think that we can drop the voltage from 12 to 6 using a rheostat and then drive the four plugs in parallel. Any constructive thoughts would be appreciated.

 

[zbang]

Wire two parallel pairs in series. Do NOT use a rheostat, you'll loose half the energy and generate lots of heat. Knowing the resistance of each plug would help (11a at what voltage?).

 

[zog]

I have a friend that wants to vaporize gas for better gas mileage. He wants to use a 12 volt car system to drive 4 glow plugs. The glow plugs will run indefinitely using 6 volts and can only handle short bursts using 12 volts. Each glow plug draws 11 amps. We think that we can drop the voltage from 12 to 6 using a rheostat and then drive the four plugs in parallel. Any constructive thoughts would be appreciated.

Sorry fellow bubblehead, we cant answer any DIY questions on this forum or we get yelled at by the moderators. Try here, they dont seem to care. http://www.electrical-contractor.net/forums/

 

[highendtron]

Well, this is a low valotage question and I am an EC...not a very big one , mind you, but I do charge for my services...the glow plugs will operate at 6 volts each and draw 11 amps , .5 ohms each... Thanks and I hope I am not violating and rules.

 

[zog]

Well, this is a low valotage question and I am an EC...not a very big one , mind you, but I do charge for my services...the glow plugs will operate at 6 volts each and draw 11 amps , .5 ohms each... Thanks and I hope I am not violating and rules.

Sorry, should have looked at your profile. It just sounded bad "My friend wants to...."

 

[highendtron]

Thanks ZOG , that looks like a useful site!!!!!! I was on the USS Nathan Hale and the USS Von Stueban, But that was many years ago!!!!

 

[gar]

090422-1707 EST

highendtron:

Instead of a series resistor use a switching circuit, on-off, maybe 100 Hz for a glow plug. The thermal time constant of a glow plug should be fairly long. Should be no need to go to 1000 Hz. Your on-off duty cycle will determine the plug temperature.

I was on BB-64.

.

 

[cpal]

Thanks ZOG , that looks like a useful site!!!!!! I was on the USS Nathan Hale and the USS Von Stueban, But that was many years ago!!!!

I think my cousin is plank owner on the Nathan Hale.

thanks for your service

 

[LJSMITH1]

First, if you are talking gasoline vapor (gas), then you will not easily 'vaporize' it without unintended ignition due to the low flash point of refined gasoline. Then, the next problem would be transporting that gasoline vapor into the combustion chamber without autoignition. Either way, you are looking at a uncontrolled (unpredictable) explosion that might hurt someone.

Gasoline and Diesel fuel injectors 'atomize' the fuel into an extremely fine mist - directly into the combustion chamber when needed. This is much more efficient than performing this task with a carburetor.

Diesels run on a fuel with a much higher flash point, and ignited with significantly higher compression ratios (23:1 vs 9:1). When a gas is compressed, it heats up. There are glow-plugs in diesel engines, and are only used to aid in the combustion process at startup when things are cold. After that, the fuel injected into the combustion chamber instantly combusts due to the high temperature of the compressed air.

A model airplane engine is another version of a diesel engine - except it is only two stroke and the glow plug's element is kept glowing by the combustion process.

 

[JFletcher]

I have a friend that wants to vaporize gas for better gas mileage. He wants to use a 12 volt car system to drive 4 glow plugs. The glow plugs will run indefinitely using 6 volts and can only handle short bursts using 12 volts. Each glow plug draws 11 amps. We think that we can drop the voltage from 12 to 6 using a rheostat and then drive the four plugs in parallel. Any constructive thoughts would be appreciated.

LJSMITH1 is correct. Not to deter you from your project, but I think your friend would realize better, not to mention much safer, improvements in fuel economy by getting a proper tune-up, ensuring the tires are inflated to the correct pressures, and so on.