Engine Combustion Network (ECN): Global sensitivity analysis of Spray A for different combustion vessels

Abstract

a b s t r a c tGlobal sensitivity analysis was conducted on Spray A of the Engine Combustion Network's (ECN) experimental conditions across different combustion vessels from different institutions. The main objective was to understand the influence of differences in boundary conditions on specific targets of interest. A list of experimental initial, boundary, and injection conditions with uncertainty ranges were identified for three different ambient conditions for these combustion vessels. Five targets including the liquid length, vapor penetration length, ignition delay, lift-off length, and soot mass in the domain were extracted from hundreds of 3D computational fluid dynamics (CFD) simulations by simultaneously perturbing all the uncertain variables. Each target was analyzed using a global sensitivity analysis (GSA) method and the relative importance of different variables towards specific targets was identified. The uncertainty in the fuel temperature was found to have a profound influence on the liquid length, however, the influence on vapor penetration length, ignition delay, and lift-off length, was rather subtle. Small uncertainties in the initial turbulence level and nozzle diameter was observed to have a significant influence on the vapor penetration. Variables sensitive to ignition delay also showed similar sensitivity to flame lift-off length. The soot mass in the domain was observed to have a closer correlation with the liquid length at least for higher ambient temperature conditions.

Large eddy simulation of a reacting spray flame with multiple realizations under compression ignition engine conditions

“…The spray experiments presented in this work were performed in a constant volume pre-burn chamber, which has provided a platform for model development and validation at engine relevant conditions [14][15][16][17][18][19][20][21][22][23][24][25][26][27]. A detailed description of the experimental setup and measurement procedures can be found in the literature [28][29][30].…”

An analysis of the structure of an n-dodecane spray flame using TPDF modelling

“…Pickett et al [9] and Meijer et al [14] reviewed the Spray A experiments in different high-temperature and high-pressure facilities in the ECN community. Some computational studies to investigate Spray A have also recently been reported [15][16][17][18][19][20][21][22][23][24][25][26][27], for example, using RANS-based transported probability density function (TPDF) method [15,23,26] and flamelet-type models [16][17][18] to demonstrate the importance of the effect of turbulence-chemistry-interaction (TCI) at diesel-engine conditions, and using large eddy simulation (LES)-type models [19-22, 24, 25] to demonstrate the capability of LES of simulating diesel spray.…”

Two-stage Lagrangian modeling of ignition processes in ignition quality tester and constant volume combustion chambers

“…Another experimental facility used in generating data for development of chemical kinetic models and computational fluid dynamic (CFD) simulations is a constant volume combustion chamber (CVCC) [13][14][15][16][17]. This is a high-pressure facility used for generating data for the Engine Combustion Network (ECN) [18][19][20], a library containing diesel spray experiments at various engine-relevant operating conditions.…”

“…The two-stage Lagrangian model (TSL) employed in this study describes mixing as a two-stage process that is seen in a frame moving downstream with the normal fluid motion. The model is capable of adopting detailed chemical kinetics while also simulating basic mixing process that are important in turbulent gaseous-jet diffusion flames [18,19,[22][23][24][25][26].…”