Reaction-space analysis of homogeneous charge compression ignition combustion with varying levels of fuel stratification under positive and negative valve overlap conditions
Abstract
Full-cycle computational fluid dynamics simulations with gasoline chemical kinetics were performed to determine the impact of breathing and fuel injection strategies on thermal and compositional stratification, combustion and emissions during homogeneous charge compression ignition combustion. The simulations examined positive valve overlap and negative valve overlap strategies, along with fueling by port fuel injection and direct injection. The resulting charge mass distributions were analyzed prior to ignition using ignition delay as a reactivity metric. The reactivity stratification arising from differences in the distributions of fuel–oxygen equivalence ratio (ΦFO), oxygen molar fraction (χO2) and temperature (T) was determined for three parametric studies. In the first study, the reactivity stratification and burn duration for positive valve overlap valve events with port fuel injection and early direct injection were nearly identical and were dominated by wall-driven thermal stratification. nitrogen oxide (NO) and carbon monoxide (CO) emissions were negligible for both injection strategies. In the second study, which examined negative valve overlap valve events with direct injection and port fuel injection, reactivity stratification increased for direct injection as the ΦFO and T distributions associated with direct fuel injection into the hot residual gas were positively correlated; however, the latent heat absorbed from the hot residualmore »
- Authors:
-
- Univ. of Michigan, Ann Arbor, MI (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
- Univ. of Michigan, Ann Arbor, MI (United States)
- Stony Brook Univ., Stony Brook, NY (United States)
- Publication Date:
- Research Org.:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Sponsoring Org.:
- National Energy Technology Laboratory (NETL); USDOE
- OSTI Identifier:
- 1338193
- Grant/Contract Number:
- AC02-06CH11357
- Resource Type:
- Accepted Manuscript
- Journal Name:
- International Journal of Engine Research
- Additional Journal Information:
- Journal Volume: 17; Journal Issue: 7; Journal ID: ISSN 1468-0874
- Publisher:
- SAGE
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 33 ADVANCED PROPULSION SYSTEMS; CFD; HCCI; NO; NVO; PFI; PVO; direct injection; reactivity stratification; homogeneous charge compression ignition; port fuel injection; negative valve overlap; positive valve overlap; computational fluid dynamics
Citation Formats
Kodavasal, Janardhan, Lavoie, George A., Assanis, Dennis N., and Martz, Jason B. Reaction-space analysis of homogeneous charge compression ignition combustion with varying levels of fuel stratification under positive and negative valve overlap conditions. United States: N. p., 2015.
Web. doi:10.1177/1468087415613208.
Kodavasal, Janardhan, Lavoie, George A., Assanis, Dennis N., & Martz, Jason B. Reaction-space analysis of homogeneous charge compression ignition combustion with varying levels of fuel stratification under positive and negative valve overlap conditions. United States. https://doi.org/10.1177/1468087415613208
Kodavasal, Janardhan, Lavoie, George A., Assanis, Dennis N., and Martz, Jason B. Mon .
"Reaction-space analysis of homogeneous charge compression ignition combustion with varying levels of fuel stratification under positive and negative valve overlap conditions". United States. https://doi.org/10.1177/1468087415613208. https://www.osti.gov/servlets/purl/1338193.
@article{osti_1338193,
title = {Reaction-space analysis of homogeneous charge compression ignition combustion with varying levels of fuel stratification under positive and negative valve overlap conditions},
author = {Kodavasal, Janardhan and Lavoie, George A. and Assanis, Dennis N. and Martz, Jason B.},
abstractNote = {Full-cycle computational fluid dynamics simulations with gasoline chemical kinetics were performed to determine the impact of breathing and fuel injection strategies on thermal and compositional stratification, combustion and emissions during homogeneous charge compression ignition combustion. The simulations examined positive valve overlap and negative valve overlap strategies, along with fueling by port fuel injection and direct injection. The resulting charge mass distributions were analyzed prior to ignition using ignition delay as a reactivity metric. The reactivity stratification arising from differences in the distributions of fuel–oxygen equivalence ratio (ΦFO), oxygen molar fraction (χO2) and temperature (T) was determined for three parametric studies. In the first study, the reactivity stratification and burn duration for positive valve overlap valve events with port fuel injection and early direct injection were nearly identical and were dominated by wall-driven thermal stratification. nitrogen oxide (NO) and carbon monoxide (CO) emissions were negligible for both injection strategies. In the second study, which examined negative valve overlap valve events with direct injection and port fuel injection, reactivity stratification increased for direct injection as the ΦFO and T distributions associated with direct fuel injection into the hot residual gas were positively correlated; however, the latent heat absorbed from the hot residual gas by the evaporating direct injection fuel jet reduced the overall thermal and reactivity stratification. These stratification effects were offsetting, resulting in similar reactivity stratification and burn durations for the two injection strategies. The higher local burned gas temperatures with direct injection resulted in an order of magnitude increase in NO, while incomplete combustion of locally over-lean regions led to a sevenfold increase in CO emissions compared to port fuel injection. The final study evaluated positive valve overlap and negative valve overlap valve events with direct injection. Furthermore, relative to positive valve overlap, the negative valve overlap condition had a wider reactivity stratification, a longer burn duration and higher NO and CO emissions associated with reduced fuel–air mixing.},
doi = {10.1177/1468087415613208},
journal = {International Journal of Engine Research},
number = 7,
volume = 17,
place = {United States},
year = {Mon Oct 26 00:00:00 EDT 2015},
month = {Mon Oct 26 00:00:00 EDT 2015}
}
Search WorldCat to find libraries that may hold this journalWeb of Science