ID 111

Evaporation and Ignition of Alternative Fuels: Paraffinic Cut Influence on Jet A-1. EXPLIC project

 

Abstract:

The paper will present experimental behaviors of some alternative fuels during evaporation or ignition process and some associated numerical results. Special emphasis has been laid on considering the influence of adding a mono- or dual-paraffinic cut in Jet A-1. The mono-modal cut is based on C10 carbon chain, the dual on C10 and C15.

The evaporation experimental apparatus is a monodisperse droplet generator. A heated coil ignites the droplets since burning droplets are required to observe evaporation. A CCD camera and microscopic telecentric lens provide accurate measurements of droplet diameter and velocity along the stream. The optical source is a non-coherent pulse laser at 690 nanometers. Comparisons of the alternative fuels and Jet A-1 experimental data are provided. The dual-modal case has the poorest behavior since the C15 cut diminishes the evaporation process. Besides, a surrogate modelling of the Alternative fuels has been proposed and its assessment has been performed using a numerical approach based on the isolated droplet theory.

The MERCATO test rig enables to study ignition of a quasi-industrial injection system under realistic conditions in terms of pressure, gas and liquid temperature. Five different alternative fuels have been considered, with three different concentrations in the mono-modal case and two different blends in the dual-modal case. Ignition performances at 0,6 bar, Tgas=233 K are compared with Jet A-1. LES two-phase flow simulations are also presented to underline the influence of fuel composition on the evaporation process. An ignition model has been used to check local ignition success or failure.