Fuel Heater Question

[tangomar]

BArmstrong,

keep of experimenting. Learn from what you are doing (of course don't do anything silly).
I found a reference regarding boiling point and temperatures. This might be old since the composition changes very often.

Boiling Point Initially, 39C
After 10% distilled, 60C
After 50% distilled, 110C
After 90% distilled, 170C
Final, 204C

Maybe you can focus on the first 50% keeping the fuel temperature around 140F (60C).

Good luck.

[MARTINSR]

Ok, here with another dumb question. In my racing days one of the things you did was to run your fuel line thru a "cool can" packed with dry ice to COOL the fuel. Cooler fuel was denser thus more fuel entered the combustion chamber to produce more power.

Since more "power" often means more efficiant isn't there going to be a trade off with the heated fuel? If you have to accelerate more to get the same given power to move the car forward?

Brian

[Christ]

Originally Posted by MARTINSR

Ok, here with another dumb question. In my racing days one of the things you did was to run your fuel line thru a "cool can" packed with dry ice to COOL the fuel. Cooler fuel was denser thus more fuel entered the combustion chamber to produce more power.

Since more "power" often means more efficiant isn't there going to be a trade off with the heated fuel? If you have to accelerate more to get the same given power to move the car forward?

Brian

More power doesn't necessarily mean more efficiency. What people overlook in that statement is that more power made w/ the same amount of fuel means more efficiency.

Hopefully, the rest of the questions answer themselves with that sentiment.

[MARTINSR]

Maybe the question I should pose is does a motor require a given amount of fuel to provide a given amount of power? If it takes X amount of power to propel the car and X amount of power is proved by Y amount of fuel (with all other factors consistant), does heating it making it less dense help at all when you still need Y amount of fuel which is in the cooled fuel?

I am just trying to understand this, I am not arguing or challenging.

Brian

[Christ]

Originally Posted by MARTINSR

Maybe the question I should pose is does a motor require a given amount of fuel to provide a given amount of power? If it takes X amount of power to propel the car and X amount of power is proved by Y amount of fuel (with all other factors consistant), does heating it making it less dense help at all when you still need Y amount of fuel which is in the cooled fuel?

I am just trying to understand this, I am not arguing or challenging.

Brian

So yeah, X fuel can only provide Y power. You got that part correct.

The problem is that unless you're using 100% throttle, you're not creating all the power you could be making for the fuel you're burning anyway. (Often, even at 100%, you're still not, but that's another story for another time.)

If you're cooling the fuel, your engine then has to input heat to the fuel to vaporize it since the fuel cools the piston tops more. One of the biggest losses in an engine is heat being shed into the combustion chamber rather than used for expansion above the piston. The more heat your fuel/air robs from the parts of the engine, the more heat it has to put back in, in a cyclic fashion.

Using exhaust heat to pre-heat the fuel helps because then the fuel (and air, if you have a WAI) goes into the combustion chamber and is already closer to engine temp, so less energy is required to heat the mix initially, which means that more of the energy released in the burn is able to act upon the piston.

Cooler, denser fuel requires more of the engine's heat stores to become combustible, which makes it less efficient, although able to produce more power overall (not per unit of fuel).

[user removed]

To add to Christ's post.

When fuel is atomized into hopefully very fine particles, the surface area of those particles increases many times above the surface area of the fuel before atomization. This allows better atomization of the fuel before combustion.

Warmer air as well as warmer fuel promote better atomization.

Transonic Combustion | Our Technology | TSCi Technology - Fuel Injection Systems

What is possible is when you get to the ideal homogenized mixture, combustion occurs simultaneously at every point in the combustion chamber, and emissions drop dramatically, to the point where you no longer need to have a catalytic converter or any other after treatment of the exhaust.

No spark is required, the heat of compression spontaneously ignites the perfectly mixed fuel air combination, even at air-fuel ratios of 80 to 1.

In other words you have solved the emissions problems by creating the most perfect mixture possible.

regards
Mech

[nemesis]

I used to have a cool can for my fuel when I used to race cars. The way it worked is you packed more fuel in, and even at less efficiency you'd make more power. Lets say you spray 10g of fuel in a cylinder at 60deg and it'll make 2.5 hp ( about 25% efficiency), so you deg temp to 20deg and now you able to pack 20g of fuel in that same cylinder and you're making 4 hp ( efficiency dropped to 20%) but you gained power even though you're using twice as much fuel.

[MARTINSR]

VERY interesting stuff guys!

There is:

1.what you know you know.
2.You know you don't know.
3.and you don't know you don't know.

That falls into number three for me! Interesting, VERY interesting.

So, now the smart ars in me, why the hell doesn't the auto manufacturer use this principle?

Is this something the average ecomodder is doing?

Brian

[Christ]

Originally Posted by MARTINSR

VERY interesting stuff guys!

There is:

1.what you know you know.
2.You know you don't know.
3.and you don't know you don't know.

That falls into number three for me! Interesting, VERY interesting.

So, now the smart ars in me, why the hell doesn't the auto manufacturer use this principle?

Is this something the average ecomodder is doing?

Brian

On average, the fuel rail runs right next to the head... the fuel does get pretty heated, but the OE's don't expect the average owner to understand that it can't get too hot or it will stall, and keep track of fuel temperature as well as the barrage of fake gauges they already don't see on their daily commute, nor understand any of them.

Remember, there has been a steady push toward auto-pilot since the 50's. Adding another thing to make the driver think would be blasphemous.

Actually, it falls more into the vehicle customization point. The OE can't custom-tune every car to it's own specifics, so they use a basic setup that works well across the board. There is always room for improvement on an OE vehicle, which is why OBD-tuners are making such a killing.

Some newer diesels can "tune" up about 300 HP into their baseline without so much as turning a wrench.

The newer Hemi's have been proven to make 500+ with a few ECM mods and bigger injectors, and still get close to the same economy (within 10%, I think it was).

There's alot more to fuel economy than the OE's can really handle with mass tuning, so they develop something that "works" and "works well" (in the economical/relatively reliable sense), and they "roll with it". Pun intended.

[MARTINSR]

Are you saying you would need to monitor the fuels heat and "adjust" it accordingly to work?

Really guys, this is so darn interesting to me, I never thought about it but everything you have said makes perfect sense!

Brian