The composition and properties of fuels listed in the ECN database are given in the tables below. Table 2.5.1 shows three oxygenated fuels (T70, GE80, and BM88) and five hydrocarbon fuels (NHPT, CET, HMN, CN80 and D2). T70 was originally used as a low-sooting fuel with a similar ignition delay as a cetane number 42.5 diesel reference fuel in order to facilitate optical diagnostics in the Sandia/Cummins optical engine (Dec, 1997). Similarly, the oxygenated fuels GE80 and BM88 had the same ignition delay as CN80 (cetane number 80) (Mueller, 2003). Ignition delays were matched only after adding a significant portion of an ignition enhancer, EHN, to BM88.

The fuel temperature (Tf) and density (ρf) at the fuel injector orifice are included in Table 2.5.1. Note that experiments were conducted at two fuel temperatures for D2 and CN80. This is because a fuel injector cooler was added after the initial D2 tests were completed. Table 2.5.1 shows that fuel density tends to decrease as temperature increases and that the fuel density of CN80 at 373 K is actually closer to the fuel density of D2 at 436 K. The fuel density can be important because fuel jets with the similar fuel density and pressure drop across the orifice will have similar jet momentum, which ultimately affects the mixing of the fuel jet. However, the fuel temperature difference had little effect on the soot level and location, or on the lift-off length and ignition delay (Pickett, 2003).

Table 2.5.1

Fuel PropertiesT70GE80BM88NHPTCETHMNCN80D2
Composition (by volume)70% TEOPa30% HMNb80% TPGMEc20% HMNb88% DBMd7% nC16e5% EHNf100% n-heptane100% nC16e or cetane100% HMNb76.5% nC16e 23.5% HMNb33.8% aromatics 65% paraffins 1.2% olefins
ρf g[kg/m3]808858907613673689724682767712
O2 h[wt%]21.525.826.500000
Ωf i[%]7.810.010.900000
Cetane Number56100158046
LHV j[MJ/kg]32.630.528.744.643.943.943.942.8
a 1,1,3,3 tetraethoxy-propane(C11H24O4)
b 2,2,4,4,6,8,8 heptamethyl-nonane (C16H34)c tri-propylene-glycol-methyl-ether (C10H22O4)
d dibutyl-maleate (C12H20O4)
e normal-hexadecane (C16H34)
f 2-ethylhexyl-nitrate (C8H17NO3)
g Density at a fuel temperature, Tf, and atmospheric pressure. The uncertainty is ±2 kg/m3.
h Oxygen weight percent
i Oxygen ratio of the fuel. See SAE 2003-01-1791.
j Lower Heating Value
k Stoichiometric air-to-fuel ratio by mass of the given fuel mixing with simulated ambient at 21% O2, 6.1% CO2, 3.6% H2O, 69.3% N2.

Table 2.5.2

Fuel PropertiesD2JCJWJSJPSRx23nC12
#2 DieselJP-8 ChevronJet-A World AverageJP-8 Syntroleum GTLJP-8 Penn St CTLJP-8 surrogatenormal dodecane
T10 [°C]211170180167192--
T90 [°C]315240251254243--
T100 [°C]350266274276270216216
Cetane Index4739???--
Cetane Number4638466234-87
Low. Heat. Value [MJ/kg]42.97543.22843.244.13842.80143.3344.17
Density at 15°C [kg/m3]843812806755.9870.2775.3752.1
Aromatics Vol. % 2711190.41.9230
H2 mass %13.2813.9?15.413.2-15.3
Sulfur [ppm]9100000
Kin. Visc. (-20°C) [mm2/s]-4.4655.24.67.5-4.7
Kin. Visc. (40°C) [mm2/s]2.35~ 1.4 (est.)----1.5
Freeze Point [°C]--57-48-51-65--10
Flash Point [°C]7347514561-83
Please refer to Kook, 2012 for a more detailed description of the fuels in Table 2.5.2.

Table 2.5.3

Fuel PropertiesG15G33G50G50AMD
MW [g/mol]223219216169186
Density [g/cm3]800835869859871
Boiling pointa [oC]287287287287224
LHV [MJ/kg]41.538.535.835.537.5
DCN (FIT)1081101128848
O2 ratio (Ω) [%]
a Boiling point refers here to the boiling temperature of the heaviest component in the fuel blend.
Please refer to Manin, 2014, "Effects of Oxygenated Fuels on Combustion and Soot Formation/Oxidation Processes" for a more detailed description of the fuels in Table 2.5.3.

Table 2.5.4

Fuel PropertiesSoy methyl
ester (SME)
Density at 288 K (kg.m-3)877
Density expected @ 373 K (kg.m-3)823
Kinematic viscosity at 313 K (mm2.s-1)3.98
Lower heating value (
Aromatics (Volume %)0
C/H and C/O mass ratios6.48/7.05
Cetane number51
Zstoich (15% O>sub>2)0.054
a Mixture fraction at critical sooting equivalence ratio. Defined as ф = 2.0 for conventional diesel and фΩ = 2.0 for biodiesel (фΩ ≡ oxygen equivalence ratio).
Please refer to Nerva, 2012 for a more detailed description of the fuels in Table 2.5.4.

Table 2.5.5

Constituent nameConstituent
Methyl palmitateC16:0C17H34O211
Methyl stearateC18:0C19H38O24.0
Methyl oleateC18:1C19H36O225
Methyl linoleateC18:2C19H34O253
Methyl linolenateC18:3C19H32O27
Soy-derived biodiesel composition per the fuel manufacturer.
Please refer to Nerva, 2012 for a more detailed description of the fuels in Table 2.5.5.