Abstract
The current energy climate has created a push toward reducing consumption of fossil fuels and lowering emissions output in power generation applications. Combined with the desire for a more distributed energy grid, there is currently a need for small displacement, high efficiency engines for use in stationary power generation. An enabling technology for achieving high efficiencies with spark ignited engines for such applications is the use of jet ignition which enables ultra-lean (λ > ~1.6) combustion via air dilution. This paper provides a comprehensive review of the development of a 390cc, high efficiency single cylinder natural gas-fueled jet ignition engine operating ultra-lean. The engine was developed as part of the Department of Energy's Advanced Research Projects Agency-Energy (DOE ARPA-E) GENSETS program. Design choices for minimizing friction are highlighted as well as test results showing further friction reduction through downspeeding. Extensive hardware optimization of the combustion system has been performed and results are presented for air-flow path optimization and the jet igniter. The efficiency benefits related to enleanment and downspeeding are analyzed using an efficiency loss breakdown based on the First Law of Thermodynamics. Through optimization efforts a peak brake thermal efficiency in excess of 34% was achieved, representing an increase of greater than 20% over the current state-of-the-industry for comparably sized CNG engines.
| Original language | English |
|---|---|
| Journal | SAE Technical Papers |
| Volume | Part F163706 |
| Issue number | 2020 |
| State | Published - 2020 |
| Event | SAE 25th Small Engine Technology Conference and Exposition: Small Powertrains - Innovating for Their Future Role, SETC 2019 - Hiroshima, Japan Duration: Nov 19 2019 → Nov 21 2019 |
Funding
1Micro-Combined Heat and Power (Micro-CHP) systems have the potential to reduce the energy and emissions burdens associated with the supply of electricity, heat, and cooling services to residences and small commercial establishments. These systems also have the potential to improve the reliability of the residential electricity supply through their redundancy with the electric grid. However, the societal-level energy, emissions, and reliability value propositions that these systems could offer through their wide-spread deployment is at risk due to the high installed costs of these systems versus the energy cost savings benefits that they generally offer. CHP systems offer their energy, emissions, and reliability value propositions via their on-site generation of electric power and subsequent productive utilization of waste heat from the generation 1This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan).
| Funders | Funder number |
|---|---|
| U.S. Department of Energy |
