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Author Topic:   BASIC FUEL CHARACTERISTICS
jammin
Administrator
posted September 04, 2001 10:48 AM
BASIC FUEL CHARACTERISTICS


GENERAL DESCRIPTION

METHANOL (Methyl Alcohol) CH30H is a volatile, highly inflammable, water-clear liquid with a mildly spirituous odour. Miscible with water or nitromethane in all proportions and almost all with petrol.
BASIC CHARACTERISTICS

Flash Point
Boiling Point
Freezing Point
Specific Gravity
Lbs/Gall approx

F C
F C
F C

61 16 148 64 -144 -97 0.796 8

NITROMETHANE CH3NO2
is an inflammable water-clear liquid with a mild odour, containing approximately 53% by weight of oxygen. Water will mix with nitromethane to the extent of 2.5% only, by volume. 110 43 214 101 -20 -29 1.13 11.25

ACETONE (Dimethyl Ketone) CH3COCH3
is a highly volatile, highly inflammable, water-clear liquid with a strong, sharp, characteristic odour. Miscible with all the chemicals listed here, and water. 0 -18 133 56 -138 -94 0.791 8

ETHER (Diethyl Ether) C2H5OC2H5
is an extremely volatile, highly inflammable, water clear liquid with a strong, lingering, characteristic odour. Miscible with all the chemicals listed here but not with water. -40 -40 95 35 -183 -116 0.714 7

BENZOLE, (Benzene) C6H6
is an inflammable water-clear liquid with a dull sweet odour Miscible in most proportions with all the chemicals listed here but not with water. 12 -11 176 80 41 5 0.879 8.75

NITROBENZENE C6H5NO2
is an inflammable, yellow, oily liquid with a strong odour of almonds. Miscible in most proportions with all the chemicals listed here but nrot with water. 190 88 412 211 41 5 1.20 12

PROPYLENE OXIDE (1 :2. Epoxypropane) CH3-CH-CH2
is an extremely volatile, very reactive, highly inflammable, water-clear liquid with a light gaseous odour. Miscible with all the chemicals listed here but only partially with water. 32 0 93 34 -155 -104 0.83 8.25

UCON LB625 (Polyalkalene glycol)
A water-clear synthetic lubricating oil with exceptionally high film strength properties. Miscible with all the chemicals listed here but not with water. 430 221 - - -25 - 32 1.0 10



Conservative Maxium Compression Ratio
Air/Fuel Ratio for Max Power lbs/lbs
Energy from Combustion B.T.U/lb
Coolling Effect (Latent heat of Vaporisation) B.T.U./lb

Use in Internal Combustion Engines

Methanol
17 : 1 4.5 : 1 9770 472
Methanol permits the use of very high compression ratios when unsupercharged or high boost pressures when supercharged. The large cooling effect increases volumetric efficiency and is of particular use in the supercharged engine reducing charge temperature after compression. A tendency to pre-ignition is most noticeable at weak mixture levels.
Nitromethane 6.5 : 1

(10 : 1 with rich mixtures)
2.5 : 1 to 0.5:1 at least
5000
258

Nitromethane enables considerable power increases to be obtained (70 percent minimum with proper use). Most often used blended with methanol, in various propor ,tions to provide power increases consistent with engine strength, etc. A tendency to detonation is reduced by an increase in mixture strength, reduction in engine temperature, reduction in compression ratio or the addition of methanol.
Acetone
17 : 1 9.4 : 1 12,500 225

approx
As a basic fuel acetone appears to have all the required characteristics, these in general Iying midway between methanol and petroleum. An exception is its very high anti-knock rating which approaches that of methanol. Other uses are as an additive to other fuels, notably to methanol to reduce pre-ignition sensitivity and promote easier starting under low temperature conditions, up to 10 percent for this purpose.
Ether
4 : 1 9.8 : 1 15,000 153
Not used as a basic fuel in spark ignition engines due to its very low knock-rating, but this characteristic is desirable in the small high-speed diesel engine where it is used in relatively large percentages (approx. 15 percent to 35 percent by volume) as an additive. Its volatile nature and low flash point make it useful as an additive tuP to 5 percent) to improve starting and give a rapid throttle response.
Benzole
15 : 1 10.8 : 1 17,300 153
Most often used blended with methanol to give a greater energy per unit volume with reduction in the latent heat vapourisation, this being a compromise often used for long distance racing where fuels other than petrol are allowed.
Nitrobenzene
not known 8 : 1 10,800 143
Blended in very small proportions with other fuels it is thought to act as an ignition accelerator. As this material has a strong odour even after combustion it is sometimes used as an additive in other fuels (approx. 0.5 percent) to mask the normal exhaust odour making it difficult to detect the base fuel type.
Propylene Oxide
not known 9.6 : 1 14,000 220
Used as an ignition accelerator additive particularly with nitromethane (up to 20 percent by volume with pure nitromethane) where noticeable increases in power are possible. Easier starting and smoother running are other benefits when blended with most other fuels (up to 5 percent)
Ucon
At 0 F this oil compares to SAE 20 at the same temperature, and at 210 F it compares to SAE 50 at the same temperature Used to advantage in all two stroke engines operating on fuel/oil mixtures. The unusually high him strength properties allowing a reduction in the amount of oil in the fuel by as much as 55 percent. Of particular use in very small high speed two stroke engines where the normal oil content can be up to 30 percent of the total volume, with the attendant restriction on the amount oF fuel that can be burnt.

NOTES
Methanol
Corrosion

Magnesium: Attacked.
Tin: White deposit (long term).
Polythene: Cracks (long term).
Paints: Most attacked severely.
Perspex: Attacked.
Handling

Poisonous; do not allow to come into contact with skin as repeated absorption may have long term effects on health.

Nitromethane Copper/Alloys: May be attacked.
Polythene: Generally resistant.
Paints: Most attacked severely.
Perspex: Attacked.
Do not allow to come into contact with caustic soda, amines or hydrazine. Pipeline pressures must be kept below 100-lb/sqlin.
Acetone
Metals: Resistant.
Polythene: Cracks (long term).
Paints: Most attacked severely.
Perspex: Attacked.
Neoprene: Some attack.
Low flash point presents considerable fire risk. Extinguish with dry powder or CO2.
Ether
Metals: Resistant.
Polythene: Cracks (long term).
Paints: Most attacked severely.
Perspex: Attacked.
Neoprene: Some attack.
Very low flash point presents serious fire and explosion risks. Vapour is heavier. than air and anaesthetic.
Benzole
Metals: Resistant.
Polythene: Generally resistant.
Paints: Some attacked.
Perspex: Some attack.
Poisonous; strong vapours must not be inhaled, may affect blood tissues permanently.
Nitrobenzene
As for benzole
Very poisonous; do not allow to come into contact with skin or inhale vapour.
Propylene Oxide
Metals: Most resistant.
Polythene: Cracks (long term).
Paints: Most attacked severely.
Perspex: Attacked.
Neoprene: Some attack.
A very reactive chemical, must not be allowed to come into contact with copper/alloys or rust, reaction may be violent.



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