Assessing the effects of ethanol addition on particulate matter emissions in GDI engines

Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018.

Bibliographic Details
Main Author: Zhang, Yihao, S.M. Massachusetts Institute of Technology
Other Authors: Wai K. Cheng.
Format: Thesis
Language:eng
Published: Massachusetts Institute of Technology 2018
Subjects:
Online Access:http://hdl.handle.net/1721.1/118678
_version_ 1811072696400740352
author Zhang, Yihao, S.M. Massachusetts Institute of Technology
author2 Wai K. Cheng.
author_facet Wai K. Cheng.
Zhang, Yihao, S.M. Massachusetts Institute of Technology
author_sort Zhang, Yihao, S.M. Massachusetts Institute of Technology
collection MIT
description Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018.
first_indexed 2024-09-23T09:10:23Z
format Thesis
id mit-1721.1/118678
institution Massachusetts Institute of Technology
language eng
last_indexed 2024-09-23T09:10:23Z
publishDate 2018
publisher Massachusetts Institute of Technology
record_format dspace
spelling mit-1721.1/1186782019-04-10T21:11:06Z Assessing the effects of ethanol addition on particulate matter emissions in GDI engines Zhang, Yihao, S.M. Massachusetts Institute of Technology Wai K. Cheng. Massachusetts Institute of Technology. Department of Mechanical Engineering. Massachusetts Institute of Technology. Department of Mechanical Engineering. Mechanical Engineering. Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. Cataloged from student-submitted PDF version of thesis. Includes bibliographical references (pages 75-78). Previous research on the effects of ethanol addition on particulate matter (PM) emissions in GDI engines show diverse results. In this thesis, an overview on three major aspects, PM formation, effects of engine operating conditions, and ethanol effects, unveils the large number of factors that can simultaneously affect PM emissions from gasoline-ethanol blends in GDI engines, partially explaining the reasons for the diverse results from previous research. A further experimental work was conducted to assess three potential ethanol effects, displacement effect, evaporative cooling effect, and oxygen content effect. The displacement effect is based on PM Index (PMI) in the literature. Ethanol has very low PMI and thus very low propensity to form PM. Therefore, the addition of ethanol replaces the high-PMI components in the gasoline, lowering PM emissions. Although the PMI value incorporates species reactivity and volatility, it does not take latent heat of vaporization (HOV) into account. The high HOV of ethanol suppresses the fuel evaporation and potentially causes more liquid fuel films, which serve as sources for PM emissions. This evaporative cooling effect was assessed along with the oxygen content effect, a widely used effect in the literature to explain why ethanol lowers PM emissions. Through the method of control variables, the displacement effect and oxygen content effect were separated out and could be assessed individually. The existence of the displacement effect was confirmed. It was also found that the oxygen content effect was negligible, while the evaporative cooling effect changed PN emission significantly. The extent of the evaporative cooling effect depended on operating conditions, such as fuel injection timing, engine coolant temperature, and load. by Yihao Zhang. S.M. 2018-10-22T18:27:57Z 2018-10-22T18:27:57Z 2018 2018 Thesis http://hdl.handle.net/1721.1/118678 1057363099 eng MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission. http://dspace.mit.edu/handle/1721.1/7582 83 pages application/pdf Massachusetts Institute of Technology
spellingShingle Mechanical Engineering.
Zhang, Yihao, S.M. Massachusetts Institute of Technology
Assessing the effects of ethanol addition on particulate matter emissions in GDI engines
title Assessing the effects of ethanol addition on particulate matter emissions in GDI engines
title_full Assessing the effects of ethanol addition on particulate matter emissions in GDI engines
title_fullStr Assessing the effects of ethanol addition on particulate matter emissions in GDI engines
title_full_unstemmed Assessing the effects of ethanol addition on particulate matter emissions in GDI engines
title_short Assessing the effects of ethanol addition on particulate matter emissions in GDI engines
title_sort assessing the effects of ethanol addition on particulate matter emissions in gdi engines
topic Mechanical Engineering.
url http://hdl.handle.net/1721.1/118678
work_keys_str_mv AT zhangyihaosmmassachusettsinstituteoftechnology assessingtheeffectsofethanoladditiononparticulatematteremissionsingdiengines