Characterisation of carbonaceous deposits on diesel injector nozzles
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
Diesel injector nozzles are highly engineered components designed to optimise delivery of fuel into the combustion chamber of modern engines. These components contain narrow channels to enhance spray formation and penetration, hence mixing and combustion. Over time, these injectors can become clogged due to fouling by carbonaceous deposits which may affect the long-term performance of a diesel engine. In this paper we explore the chemical composition and structure of deposits formed within the nozzle at the nanometre scale using electron microscopy. We focus on comparing deposits generated using a chassis dynamometer-based test with Zn fouled fuel with a DW10B dirty up test. We have developed and applied a method to precisely section the deposits for ‘top view’ scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analysis of the morphology and relative accumulation of deposits formed during chassis dynamometer and engine based dirty-up tests. We extend this analysis to finer length scales through lift-out of ~70 nm thick electron transparent cross section foils, including both the metal substrate and deposit, using focussed ion beam (FIB) machining. These foils are analysed using scanning transmission electron microscopy (STEM) and STEM-EDS. These thin foils reveal thin-film growth and chemical stratification of Zn, C, O and other elements in the organic deposit layers developed during growth on the steel substrate during industry standard fouling tests.
Date Issued
2020-08-15
Date Acceptance
2020-03-12
Citation
Fuel: the science and technology of fuel and energy, 2020, 274, pp.1-9
ISSN
0016-2361
Publisher
Elsevier
Start Page
1
End Page
9
Journal / Book Title
Fuel: the science and technology of fuel and energy
Volume
274
Copyright Statement
© 2020 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/
Sponsor
Shell Research Limited
Royal Academy Of Engineering
Shell Global Solutions International BV
Identifier
https://www.sciencedirect.com/science/article/pii/S0016236120306244?via%3Dihub
Grant Number
4550111366
RF/129
PO 4550133349
Subjects
0306 Physical Chemistry (incl. Structural)
0904 Chemical Engineering
0913 Mechanical Engineering
Energy
Publication Status
Published
Date Publish Online
2020-04-20