Saybolt Universal Seconds (SUS), which is the time in seconds for 60 milliliters of oil to flow through a standard orifice at a given temperature. Although the two terms are regularly interchanged, which is further complicated due to 1 cP being equal to 1 cSt, they are in fact two slightly different terms. The proper way to identify oil viscosity, in cgs units, is either in centistokes (cSt), or more appropriately, centipoise (cP). 1 cP = 0.01 poise = 0.01 gram per cm second = 0.001 Pascal second = 1 milliPascal second = 0.001 N s/m2.For example: 100 cSt tested at 210 F is equivalent to 466.4 SUS because 100 x 4.664 = 466.4. The result is the cSt value converted to SUS. Multiply the cSt value by 4.664 if the test temperature was 210 F. With filling, cleaning and drying at -20☌, which requires a supply of dry air, approximately 15 minutes can be saved.How do you convert viscosity to centipoise?Īn easy way to convert from kinematic to dynamic viscosity is to multiply the value in centistokes by the specific gravity of the liquid to get the corresponding value in centipoise. Jet A1 JF1411 and reference standard Jet N2B were tested as tables scan with variable steps from -20☌ to -56☌.Īll samples were filled at +20☌.Jet A JF1107 was tested as a range scan from -20☌ to -55☌ with 1☌ steps.Therefore typically viscosity of JET A is higher and JET A also shows a steeper increase of viscosity with decreasing temperatures. The fuels differ in their freeze point specifications (-40 ☌ for JET A and -47 ☌ for Jet A1). While fuel JF1107 is type Jet A, fuel JF1411 is type Jet A1. Too high viscosity prevents fine enough atomization of the jet fuel - consequently, droplet evaporation is not possible.ĭata are available for two different jet fuels and a jet fuel reference standard. The APUs' ability to start depends on the viscosity of the jet fuel at such low temperatures. During these periods, the fuel's temperature drops down to ambient temperature. These APUs can be inactive for long periods (15 hours or more) at flying height. This is especially relevant for so-called Auxiliary Power Units (APUs), which are small gas turbines that need to start up on command. In order for jet fuel to endure long cold soak periods at temperatures believed to be -40☌ or lower, knowing the viscosity of jet fuel at such low temperatures becomes increasingly important. Aviation gasoline: Also known as AVGAS, only for use with piston or Wankel engines.Low volatility kerosene: Gives good thermal stability and contains only a low amount of highly volatile components like toluene or benzene.High flash point kerosene: Provides more fire security because of a min.Wide-cut fuels must fulfill a density specification, but not all of them must fulfill viscosity specifications. Wide-cut fuels: These are a mixture of kerosene and gasoline and can be used in an extended temperature range.It must fulfill viscosity specifications. Kerosene - Jet A-1 is the most common type in civil aviation, JP-8 is the military equivalent, TS-1 has improved low-temperature properties.The following aviation fuel types are available: Depending on their specific use they additionally contain additives. They consist mainly of hydrocarbons (paraffins, cycloparaffins, naphthenes, aromatics and olefins, whereby paraffins and cycloparaffins are the main components. Aviation fuels in general are fuels suitable for use in aircrafts powered by turbojet, turboprop or piston engines.
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