Hydrogen double compression-expansion engine (H2DCEE): A sustainable internal combustion engine with 60%+ brake thermal efficiency potential at 45 bar BMEP
Journal article, 2022

Hydrogen (H-2) internal combustion engines may represent cost-effective and quick solution to the issue of the road transport decarbonization. A major factor limiting their competitiveness relative to fuel cells (FC) is the lower efficiency. The present work aims to demonstrate the feasibility of a H-2 engine with FC-like 60%+ brake thermal efficiency (BTE) levels using a double compression-expansion engine (DCEE) concept combined with a high pressure direct injection (HPDI) nonpremixed H-2 combustion. Experimentally validated 3D CFD simulations are combined with 1D GT-Power simulations to make the predictions. Several modifications to the system design and operating conditions are systematically implemented and their effects are investigated. Addition of a catalytic burner in the combustor exhaust, insulation of the expander, dehumidification of the EGR, and removal of the intercooling yielded 1.5, 1.3, 0.8, and 0.5%-point BTE improvements, respectively. Raising the peak pressure to 300 bar via a larger compressor further improved the BTE by 1.8%-points but should be accompanied with a higher injector-cylinder differential pressure. The lambda of ~1.4 gave the optimum tradeoff between the mechanical and combustion efficiencies. A peak BTE of 60.3% is reported with H2DCEE, which is ~5%-points higher than the best diesel-fueled DCEE alternative.

Hydrogen combustion

CFD

High efficiency

Compression ignition

Hydrogen engine

Direct injection

Author

Rafig Babayev

Chalmers, Mechanics and Maritime Sciences (M2), Combustion and Propulsion Systems

Hong G. Im

King Abdullah University of Science and Technology (KAUST)

Arne Andersson

Volvo Group

Bengt Johansson

Chalmers, Mechanics and Maritime Sciences (M2), Combustion and Propulsion Systems

Energy Conversion and Management

0196-8904 (ISSN)

Vol. 264 115698

Subject Categories

Other Mechanical Engineering

Aerospace Engineering

Energy Engineering

DOI

10.1016/j.enconman.2022.115698

More information

Latest update

1/10/2023