AUTHOR=Garcia Erick , Triantopoulos Vassilis , Trzaska Joseph , Boehman André L. , Taylor Maxwell , Li Jian 

TITLE=Development of a high thermal efficiency heavy-duty engine

JOURNAL=Frontiers in Thermal Engineering

VOLUME=Volume 4 - 2024

YEAR=2025

URL=https://www.frontiersin.org/journals/thermal-engineering/articles/10.3389/fther.2024.1517404

DOI=10.3389/fther.2024.1517404

ISSN=2813-0456

ABSTRACT=The U.S. Department of Energy Supertruck 2 program placed emphasis on development of heavy-duty trucks with high freight efficiency using commercially realizable technology suites. This paper describes the research and development process used to pursue a high thermal efficiency heavy-duty engine under Supertruck 2. The team focused on over-expanded engine cycles and advanced piston designs. This paper describes how single-cylinder engine studies using thermal barrier coated pistons, high compression pistons, and over-expanded cycles informed the development process of a multi-cylinder demonstration engine that achieved 49.9% peak thermal efficiency. While tailoring the injection strategy and other control parameters optimized the demonstration engine, more than half of the efficiency improvement came from the over-expanded cycle.