Assessment of flammability of crankcase gases in a spark-ignition and hydrogen engine

IFP Energies nouvelles (IFPEN) est un acteur majeur de la recherche et de la formation dans les domaines de l’énergie, du transport et de l’environnement. De la recherche à l’industrie, l’innovation technologique est au cœur de son action, articulée autour de quatre priorités stratégiques : CLIMAT, ENVIRONNEMENT ET ÉCONOMIE CIRCULAIRE, ÉNERGIES RENOUVELABLES, MOBILITÉ DURABLE et HYDROCARBURES RESPONSABLES.

L’engagement d’IFPEN en faveur d’un mix énergétique durable se traduit par des actions visant :

• à gagner en efficacité énergétique ;
• à réduire les émissions de CO2 et de polluants ;
• à améliorer l’empreinte environnementale de l’industrie et des transports ;

tout en répondant à la demande mondiale en mobilité, en énergie et en produits pour la chimie.

Dans cet objectif, IFPEN développe des solutions permettant, d’une part, d’utiliser des sources d’énergie alternatives et, d’autre part, d’améliorer les technologies existantes liées à l’exploitation des énergies fossiles.

Assessment of flammability of crankcase gases in a spark-ignition and hydrogen engine

The spark ignition engine fueled by hydrogen is a possible solution to decarbonize the ground transport. Compared to the fuel cell, it benefits from the advantages of internal combustion and fossil fuel engines, particularly the technological maturity, the existence of production chains and the durability. This results in a possible rapid development at moderate cost, accentuated by a reduced need for noble metals and hydrogen purity.

The control of hydrogen combustion requires the adaptation of internal combustion engine, test bench and tools for combustion analysis. It also requires the control of hydrogen content in the crankcase to limit any flammability which can favor the lubricant combustion or the engine damage. The presence of hydrogen in the crankcase is favored by the passage of the small molecule through the piston rings. Hydrogen ignites easily due to its large flammability range and its low ignition energy. The acceptable limits of concentration of hydrogen still need to be estimated depending on the composition of the crankcase gases containing not only air but also combustion gases and especially water vapor and oil vapors. The leaks through the rings can be estimated in the crankcase as a function of engine conditions and the resulting hydrogen losses can be considered for combustion analysis.

This study focuses on the assessment of flammability of crankcase gases in a spark-ignition and hydrogen engine. It has three objectives: define the lower flammability limits of crankcase gases based on their composition, evaluate hydrogen leaks through the segmentation and consider the resulting hydrogen losses in the combustion analysis.

The work will therefore consist of:

• Establish an assessment 1/ of the flammability limits of crankcase gases containing hydrogen according to their composition and 2/ of the segmentation leaks as a function of engine conditions, both based on internal knowledge or on information available in scientific and technical literature;
• Compare the results from this assessment with experimental data from available hydrogen thermal engine benches;
• Propose additional experiments if relevant;
• Introduce the identified correlations into an existing combustion analysis tool in Matlab.

Requested profile and skills:

The student must be in internship for Master M2 or equivalent education level with a good knowledge of the internal combustion engine and Matlab-type programming language to complete the tool under development. Knowledge of hydrogen combustion is a plus but not essential.

• The candidate must be motivated to work in a research environment on future mobility and air quality.
• Finally, he must have the ability to work in a team and communicate on his work.

Specialization keywords : thermodynamic, fluid mechanics, programming

Duration and dates : 6 months in 2025

Practical information : The internship will take place at IFP Energies nouvelles in Solaize (south of Lyon). The internship will be granted with a financial compensation (unless granted otherwise).

Interested ? Send a letter of motivation and a CV !