Saturday, April 20, 2013

Bahan bakar pesawat terbang (bagian 2 - karakter fisik dan sifat)

(bahasa Inggris: Aircraft fuel physical characteristic)

Jet A and Jet A-1 memiliki titik nyala (flash point) di atas 38 °C (100 °F), dan suhu terbakar sendiri (autoignition temperature) pada 210 °C (410 °F).

Perbedaan Jet A and Jet A-1
Perbedaan utama Jet A and Jet A-1 adalah Jet A titik bekunya lebih tinggi (−40 °C (−40 °F) vs. −47 °C (−53 °F) pada Jet A-1), dan diwajibkan menggunakan additive anti-static pada Jet A-1.

Jet A-1 danJet A dikenali pada truk dan fasilitas penyimpannya dengan sistem penomoran UN (PBB-red) 1863

Sifat fisik Jet A and Jet A-1
Jet A-1 dipersyaratkan memenuhi
  • DEF STAN 91-91 (Jet A-1),
  • ASTM specification D1655 (Jet A-1), and
  • IATA Guidance Material (Kerosene Type), NATO Code F-35.
Jet A fuel dipersyaratkan sesuai dengan spesifikasi ASTM D1655.



Dalam bentuk tabel:

Jet A-1Jet A
Flash point42 °C (108 °F)51.1 °C (124.0 °F)
Autoignition temperature210 °C (410 °F)
Freezing point−47 °C (−53 °F)−40 °C (−40 °F)
Open air burning temperatures260–315 °C (500–599 °F)
Density at 15 °C (59 °F)0.804 kg/L (6.71 lb/US gal)0.820 kg/L (6.84 lb/US gal)
Specific energy43.15 MJ/kg43.02 MJ/kg
Energy density34.7 MJ/L35.3 MJ/L

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catatan:

1 us gallon = 3.785411784 liter

1 pound (lb) = 0.45359237 kg

1 lb/us gal = 0.45359237    /    3.785411784 kg/liter
= 0.1198264273168966 kg/liter
= 8.345404452019332 liter/kg

6 lb/us gal = 0.7189585639013798 kg/liter
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from P&WA handbook. These figures are for a standard day; 59 degrees F (15 degrees C) and 29.96 inches of Mercury barometric pressure. These figures are in pounds per gallon instead of gallons per pound.

JP-4 6.55
JP-5 6.82
Kerosene 6.7
Jet A 6.74
Gasoline 5.87
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At 15 degrees Celsius...
Gasoline is .690 density (a liter of gas weighs .690 grams or .69 of a kilo)...
JP-4 is .78 density
Jet A-1 is .812 density (a liter of Jet A-1 weighs .812 grams)
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These weights should not be used if actual weights are available. Some of the standard weights are:
Gasoline ............................................... 6 lb/US gal
Jet A, Jet A-1 .................................... 6.8 lb/US gal
Jet B ...................................................6.5 lb/US gal
Oil ......................................................7.5 lb/US gal
Water .....................................................8.35 lb/US gal
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Jet B
Jet B merupakan komposisi naphtha-kerosene yang dipergunakan pada cuaca dingin. komposisinya 30% kerosene dan 70% gasoline, titik bekunya rendah yaitu of −60 °C (−76 °F) sehingga titik nyalanya pun rendah juga. Digunakan di AS dan beberapa pesawat militer.

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