## 5 LBV of Key Hydrocarbon Components in Aviation Fuel
### LBV of N-Alkanes in Aviation Fuel
The testing platforms constructed can better avoid heat dissipation and generate stable flame fronts, and the correction principles for flame stretch effects are also more refined. For example, the 1992 study by [PERSON] et al.--conducted without an appropriate flame stretch correction method--claimed that n-butane could reach an LBV of 82 cm/s at 400 K and 1 atm, a figure now regarded as a considerable overestimation [83]. Moreover, the spherical flame method yields relatively small values with good consistency across different studies. In contrast, the values obtained from the stagnation flame method are relatively high, with significant differences among the data. From the perspective of the uncertainty range, except for the data from 2010 and unmarked data, the standard deviations of LBV_max measured by the spherical flame method and the stagnation flame method were similar, both around 1 cm/s. The standard deviation of LBV_max measured by the externally heated diverging channel method was larger, around 3 cm/s. Additionally, both the Bunsen burner method and the heat flux method achieved standard deviations for LBV_max of around 1 cm/s [6]. However, when testing blended fuel mixtures or when the equivalence ratio leaned more toward the fuel-lean or fuel-rich side, the uncertainty of the test results typically increased [34; 35]. The externally heated diverging channel method, as \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Carbon** & \multicolumn{2}{c}{**Experimental Conditions**} & \multicolumn{2}{c}{**LBV Measurement**} & \multicolumn{1}{c}{**Ref.**} \\ \cline{2-5}
**Number** & **P (atm)** & **T (K)** & **Methods** & **Ref.** \\ \hline
1–8 & - & - & - & [22; 77] \\  & & 338, 360, 400, & Externally heated & \\
10 & 1 & 470, 500, 610, & diverging channel & [69] \\  & & 650 & method & \\
10 & 1, 2 & 470 & Spherical flame method & [69] \\
10 & 1 & 403 & Stagnation flame method & [74] \\
10 & 1 & 400, 425 & Spherical flame method & [76] \\
10 & 1 & 360, 400, 470 & Stagnation flame method & [72] \\
10 & 1 & 400 & Externally heated & [78] \\  & & & diverging channel & \\
10 & 1 & 398 & Stagnation flame method & [13] \\
10 & 1 & 398 & Spherical flame method & [79] \\
10 & 1 & 398 & Spherical flame method & [80] \\
10 & 1 & 398 & Spherical flame method & [81] \\
12 & 1, 2, 3, 4 & 400, 425, 450 & Spherical flame method & [24] \\
12 & 1 & 400 & Spherical flame method & [82] \\
12 & 1 & 403 & Stagnation flame method & [74] \\
12 & 1 & 400, 470 & Stagnation flame method & [72] \\
12 & 1 & 400, 425 & Spherical flame method & [76] \\
12 & 1 & 400 & Spherical flame method & [82] \\
14 & 1 & 423, 443 & Stagnation flame method & [18] \\
14 & 1 & 423, 443 & - & [75] \\
16 & 1 & 443 & Stagnation flame method & [18] \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Information on LBV tests for different n-alkanes. a newer measurement technique, offers the advantage of a wide temperature measurement range. However, due to varying approaches in handling external heat control and flame deformation near the outlet wall, this method is currently in the experimental stages. It can be observed that the LBV results obtained through this method are similar to those from the spherical flame method, but further validation is required to enhance its accuracy. Figure 7 compiles LBV measurements for n-alkanes. The overall trend from highest to lowest LBV is 443 K > roughly 423 K > roughly 400 K > 373 K > 353 K, indicating that temperature exerts a stronger influence on LBV than carbon chain length. Around 400 K, the LBV differences among n-pentane, n-heptane, n-nonane, n-decane, and n-dodecane are fairly small, consistent with [PERSON] and [PERSON] [67]. However, as the carbon number increases, there are certain variations in factors such as chemical structure, bond energy, thermophysical parameters, transport properties, and adiabatic flame temperature (\(T_{\text{ad}}\)), which may lead to trends in LBV.