Title
Ramped Versus Square Injection Rate Experiments in a Heavy-Duty Diesel Engine
Author
Willems, R.
Willems, F.
Simpson, T.
Albrecht, B.
Deen, N.
Somers, B.
Publication year
2020
Abstract
CO2 regulations on heavy-duty transport are introduced in essentially all markets within the next decade, in most cases in several phases of increasing stringency. To cope with these mandates, developers of engines and related equipment are aiming to break new ground in the fields of combustion, fuel and hardware technologies. In this work, a novel diesel fuel injector, Delphi’s DFI7, is utilized to experimentally investigate and compare the performance of ramped injection rates versus traditional square fueling profiles. The aim is specifically to shift the efficiency and NOx tradeoff to a more favorable position. The design of experiments methodology is used in the tests, along with statistical techniques to analyze the data. Results show that ramped and square rates - after optimization of fueling parameters - produce comparable gross indicated efficiencies. Tests were carried out at 1200 and 1425 rpm; for the latter engine speed peak efficiency was attained at considerably lower NOx levels by applying a ramped injection rate. Particulate matter emissions, on the other hand, are generally lower with the use of square profiles. Heat release analysis further reveals that ignition delays in ramped rate operation are quite long, hinting at vastly different spray behavior. The relatively low loads applied in this work only sustain the delays further. Altogether, this causes the potential of the rate shaping capabilities to be underexploited, as direct control over the burn rate is limited with the combustion system used in this work. The results emphasize the need to carefully select ramp slopes for a particular engine geometry, load and speed point, and additional operating parameter settings.
Subject
Industrial Innovation
Diesel engines
Compression engines
Particulate matter
PM
Statistical analysis
Diesel fuels
Data exchange
Combustion processes
To reference this document use:
http://resolver.tudelft.nl/uuid:f475d06f-54cc-4dcd-b9b8-7f7079687f03
DOI
https://doi.org/10.4271/2020-01-0300
TNO identifier
875867
Publisher
SAE International
ISSN
1487-191
Source
SAE Technical Papers, WCX SAE World Congress Experience
Document type
conference paper