Research into climate-friendly large engines for shipping is being further expanded at the Technical University of Munich (TUM). The IBFlex project is creating a modern research infrastructure that enables alternative fuels such as ammonia and methanol to be investigated under realistic conditions. The aim is to experimentally analyze new combustion processes and accelerate the development of low-emission dual-fuel engines for maritime applications.

The project focuses on upgrading an existing Rapid Compression Expansion Machine (RCEM) at the Chair of Sustainable Future Mobility (SFM). The research activities concentrate on two key areas:

1. Upgrading the RCEM for flexible combustion processes

The existing RCEM will be developed from a diffusive combustion process, similar to high-pressure direct injection (HPDI), into a homogeneous combustion process based on the principle of port fuel injection (PFI). This will make it possible to investigate different injection and combustion strategies using ammonia and methanol under comparable conditions.

The existing FTIR measurement technology will also be expanded. New modules will enable oxygen measurements and the analysis of ammonia burnout, among other capabilities. The modernized infrastructure will thus provide the basis for detailed research into the ignition of diesel or biodiesel pilot fuels in alternative fuel-air mixtures.

2. Improving optical measurement technology and spray diagnostics

Another key focus is the modernization of optical diagnostics. Additional optical access points in the cylinder head will improve existing measurement methods such as OH* chemiluminescence, shadowgraphy, and Mie scattering.

In addition, a new methanol injector and a PIV measurement system (Particle Image Velocimetry) will be acquired. These will enable highly time-resolved analysis of injection processes and spray development for both homogeneous and diffusive combustion processes.

With IBFlex, TUM is building on the successful predecessor projects AmmoniaMot and FlexDi and strengthening its role in the development of climate-friendly combustion technologies. The project therefore makes an important contribution to the decarbonization of shipping and to Germany’s technological competitiveness in the field of sustainable maritime propulsion systems.