Experimental study of the spray ignition characteristics of hydro-processed renewable jet and petroleum jet fuels in a constant volume combustion chamber

In this study, the spray ignition characteristics of conventional aviation fuels (JP-5 and Jet-A1) and hydroprocessed renewable jet fuel (HRJ) were investigated in a constant volume combustion chamber at chamber pressures of 10, 15, and 20 bar and temperatures ranging from 600 K to 818 K. It was found that all the ignition delays profile were shortened exponentially with increases in the chamber temperature. The HRJ fuel was found to obtain a shorter ignition delay as compared to JP-5 and Jet-Al by as much as 74% and 67%, respectively. In addition, the first stage ignition delay for HRJ fuel was 50% shorter than that for the petroleum jet fuels. The reactivity of the fuels increased with increases in the chamber pressure. The HRJ fuel was 1 ms and 2 ms earlier than Jet-A1 and JP-5, respectively, in terms of achieving a combustible mixture at low and intermediate chamber pressures. The chamber pressure was also found to be sensitive to the formation of the NTC zone for all of the tested fuels.

Automated summary

This study investigated the spray ignition characteristics of different fuels under various conditions, finding that hydroprocessed renewable jet fuel exhibited faster reactivity and that the reactivity of all fuels increased with chamber pressure.