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Arouse the DAMPFHAMMER!
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VP makes a wonderful 103 octane unleaded oxygenated race fuel & the average cost per gallon was $8.00 in 2008
Nice, this would help for some added ponies. What I had in mind was Hydrazine, a German invention with the chemical formula C2H4, which is a that dangerous, very toxic, lethal and one of the most powerful fuels. The power lays not in the heating value, which is obviously very low at 5.5 kWh/kg (pump gas has 12 kWh/kg), but it lays in the fact that it tend to explode instead of to burn. Explode means a simultaneous chemical reaction in the chamber, that and the fact it has a stoichiometric AFR of 4 something to 1. Pump gas need about 14.7:1 kg air per kg fuel. That means VE is not the factor alone to create power, you can cram that much fuel into the chamber. A 20 % Nitro-Methane mixture has about the same stoichiometric AFR, but burns much more controlled then Hydrazine. In the early 2000's at least one member of the drag race scene, I know, used that and pimped his K26 to over 600 wph, which was that time almost 50 % more power then competitors. It's forbidden in many kind in race series, in most industries to use as fuel because of it's very edgy behaviour. With that a 400 whp 2-Liter-NA engine redlined at 9000 rpm would be maybe possible. The 400 ftlb's still would be challenging, as this would mean double of the actual torque with pump fuel. I am not saying it is impossible, but very near to that term.

Only a few guys ever used that fuel in the 60'ies, some of the few paid with their live for that. It was forbidden after some accidents that time for many race classes. Hydrazine need well experienced handling, a dedicated fuel management and fuel logistic. Must be Oxydator free as Hydrazine tend to react with oxygen instantaneously without any source of ignition spark (hypergolic property). The theoretical octane number is 0 and infinite at the same time as it never would knock but explode what can have effects like knock ;).
 

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A 20 % Nitro-Methane mixture has about the same stoichiometric AFR, but burns much more controlled then Hydrazine.
interesting. Do you think this 20% Nitro-Methane mixture can or could be blended with 93 octane or 100 ron? I am not planning on doing that by any means, however,the concept is something I would like to learn about.

I have always been interested in fuel cooling by a in-line intercooler using a seperate electric pump for a wet to wet intercooler (fuel cooler). There maybe a way to copy a A/C system and use a certain or typical gas similar to R401A refridgerant to cool fuel before the fuel rail. There maybe a way to have a pressure regulated storage cylinder pre-fuel rail instead of losing the un-used fuel back to the return line, which would lose the cooled fuel. The same concept could be possible the return line could go back to the pressurized regulated storage cylinder. It may require using two pressurized cylinders...
 

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Arouse the DAMPFHAMMER!
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Discussion Starter · #1,083 ·
Do you think this 20% Nitro-Methane mixture can or could be blended with 93 octane or 100 ron?
CH3NO2 is highly polar as a molecule, pump gas is it not except the hydrogen-brigde-connections, therefore I believe, I don't know it, they would solve into each other in some way and can be blended into each other. But keep in mind those fuels are totally different. While Nitro-Methane burns slow but some sort of simultanious because of the there will be no clear flame front more a homogeniouse combustion start based on increased temperature and pressure, I would say it is, even blended with gasoline, not predictable hand-able. Especially as Nitro comes with it's oxygen almost already, just need a bit of oxygen to complete the combustion, in a 14:1 surrounding with pump fuel, I would see some control issues with it. I have no experience with it, just from a point of brain storming to that.

in-line intercooler using a seperate electric pump for a wet to wet intercooler (fuel cooler)
For which application? The cooling need to be adapted to the MAP and MAT of the plenum conditions, also which fuel? Different fuels have different ranges of vaporization temperatures, e.g. cooling of alcohols can be lead into serious issues, gasoline is somewhat more tolerant because of the wider vap.-temp. spectre.
 

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For which application? The cooling need to be adapted to the MAP and MAT of the plenum conditions, also which fuel? Different fuels have different ranges of vaporization temperatures, e.g. cooling of alcohols can be lead into serious issues, gasoline is somewhat more tolerant because of the wider vap.-temp. spectre.
The application would be race car or even a aggressive street build, fuel being 93 pump gas to be universal in application. I am imagining the fuel coming from the fuel tank going through a in-line fuel cooler, such as a heat exchanger that has a shell around a type of coil that the fuel passes through. The shell would possibly need a baffle plate inside or maybe not. I am seeing this as a electric fluid pump to pass the coolant agent in and out fo the shell.

I am think a seperate tank or holding type tank that can be filled with ice or ice block (would last longer than crushed ice itself). The electric fluid pump can handle that operation. I have seen a cylinder that holds a large amount of ice and has a fuel coil line that passes fuel in and out of the container. This would work as long as the ice holds it shape, example fill a plastic party cup with water, then freeze so it is a block and the ice cylinder can be inserted in the container by a threaded cap and the ice block would rest inside of the coil line. This way a electric fluid pump would not be needed.
 

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Hydrazine: N2H4. It is cancerogenic besides forming explosive gels when mixed with nitromethane. You also won't even be able to buy it unless you are into chemistry.

Nitromethane is not miscible with petrol/gas.
As it has a low knock resistance in fuel use, it is commonly used mixed with with methanol. Both mix in any ratio.
I have used it in small RC model engines and it makes then go like stink. I love the smell of burned nitromethane.
The very small ones don't even run well in first place without copious amounts of nitromethane.

fuel cooling, let's see how much it can do.
heat capacity of fuel is about 2 J/gK.
Lets assume 300 HP engine needing 25 g of fuel per second and at an AFR of 13:1 325 g of air per second.
heat capacity of air is about 1 J/gK

Now let's assume you cool down you fuel by 30K, so freezing temperature on a summer day.
The energy required to reheat 25 g of fuel cooled down by 30K is 25*30*2 = 1500 J.
Now conveniently as we look at a time span of 1 second, this would correspond to 1.5kW of cooling power.
Now we dump those 1500 J onto our 325 g of air. The temperature of the air would drop by 1500/325= 4.6K or roughly 5°C.

Now these 5°C might add 1-2% of power or in case of our 300HP example 3-6HP.
To get these, you need to be able to provide about 2HP of cooling power.

This is simplified, but get's you a first idea on what the effort is worth.
 

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Hydrazine: N2H4. It is cancerogenic besides forming explosive gels when mixed with nitromethane. You also won't even be able to buy it unless you are into chemistry.

Nitromethane is not miscible with petrol/gas.
As it has a low knock resistance in fuel use, it is commonly used mixed with with methanol. Both mix in any ratio.
I have used it in small RC model engines and it makes then go like stink. I love the smell of burned nitromethane.
The very small ones don't even run well in first place without copious amounts of nitromethane.

fuel cooling, let's see how much it can do.
heat capacity of fuel is about 2 J/gK.
Lets assume 300 HP engine needing 25 g of fuel per second and at an AFR of 13:1 325 g of air per second.
heat capacity of air is about 1 J/gK

Now let's assume you cool down you fuel by 30K, so freezing temperature on a summer day.
The energy required to reheat 25 g of fuel cooled down by 30K is 25*30*2 = 1500 J.
Now conveniently as we look at a time span of 1 second, this would correspond to 1.5kW of cooling power.
Now we dump those 1500 J onto our 325 g of air. The temperature of the air would drop by 1500/325= 4.6K or roughly 5°C.

Now these 5°C might add 1-2% of power or in case of our 300HP example 3-6HP.
To get these, you need to be able to provide about 2HP of cooling power.

This is simplified, but get's you a first idea on what the effort is worth.
yeah it does not seem to be worth it. Thank you for addressing the subject I brought up with so much detail. You and LotusElise always take the time to give educational answers, I am grateful for the both of you.

So the RRC IM is on it's way. I am tempted to cut the plenum off and do some shaping...
 

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Arouse the DAMPFHAMMER!
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Nitromethane is too polar as it is carrying internal charges to mix with non-polar solvents such as in gasoline. The molecule only appears neutral as the internal charges compensate each other. The negative change on the oxygen is actually distributed around the two oxygen atoms on the nitro group.
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Nitromethane is also acidic, weak, but still acidic. It can lose a proton on the left CH3 group. The positive charge on the nitrogen atom pulls electrons out of the adjacent carbon atom weakening the carbon-hydrogen bonds. So if you "pull" hard enough with a base, one proton can be stripped off. As hydrazine is a basic compound, it slowly forms a salt with nitromethane.
This is the gel like substance the 60ties drag racers reported about forming shortly after bending the fuel. It is an explosive (literally) compound of low stability.
 

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Arouse the DAMPFHAMMER!
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Discussion Starter · #1,089 ·
Nitromethane is too polar as it is carrying internal charges to mix with non-polar solvents such as in gasoline...As hydrazine is a basic compound, it slowly forms a salt with nitromethane.
Thanks for your reply and explanation why it doesn't solve in liquidize Hydrocarbons like gasoline is it, which has only hydrogen-bridge-bonds.
 

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There are not even hydrogen bridge bonds in hydrocarbons. The bonds are not polar enough for this. You commonly need hydroxide, nitro, amino or at least carbonyl groups in conjunction with other polar groups in order for these to play a significant role.
What holds hydrocarbon fluids "together" are mostly induced dipole-dipole interactions. Fluctuations in the electron distribution along the molecule lead to temporarily unequal charge distributions. So if one end of the molecule carries momentarily more electrons than the other end, these end can interact with an other molecule in the same dynamic state.
These forces are weak. This causes hydrocarbons to have a low boiling point and low heat of evaporation.
 

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Arouse the DAMPFHAMMER!
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Discussion Starter · #1,091 ·
There are not even hydrogen bridge bonds in hydrocarbons. The bonds are not polar enough for this. You commonly need hydroxide, nitro, amino or at least carbonyl groups in conjunction with other polar groups in order for these to play a significant role.
What holds hydrocarbon fluids "together" are mostly induced dipole-dipole interactions. Fluctuations in the electron distribution along the molecule lead to temporarily unequal charge distributions. So if one end of the molecule carries momentarily more electrons than the other end, these end can interact with an other molecule in the same dynamic state.
These forces are weak. This causes hydrocarbons to have a low boiling point and low heat of evaporation.
Thanks for the very helpful explanation @Lotus.
 
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