• Aleksandar Ribnishki

  • Theme:Chemical Energy Converters
  • Project:Knock in Direct Injection Hydrogen Internal Combustion Engines
  • Supervisor: Sam Akehurst ,Hao Yuan ,Stefania Esposito
  • Industry Partner: JLR
  • The Gorgon's Head - Bath University Logo


Alex recently graduated from the University of Bath with an MEng in Mechanical with Automotive Engineering, during which he undertook a three-month placement at Horstman Defence Systems Limited and a year-long placement at Mammoet. It was during these placements that he developed an interest towards the research and development of low carbon and carbon neutral systems. Alex’s passion for internal combustion engines led him to join the university’s ICE Formula Student team – Team Bath Racing, during his penultimate year. During his time with the team, Alex conducted engine simulations of the team’s KTM 500 engine and designed the intake system. For his final year project titled ‘Analytical and Numerical Modelling of the Surface-to-Volume Ratio of a Two-Stage Wankel Engine’ and supervised by Dr Aaron Costall, Alex investigated the effects that the geometrical parameters of a two-stage Wankel engine have on its surface-to-volume ratio and proposed an optimised engine design for reduced thermal losses and improved thermal efficiency.


  • My go-to comfort-binge TV series is Friends
  • I collect LEGO sets
  • I have been skiing since I was 12
  • I am afraid of heights

Knock in Direct Injection Hydrogen Internal Combustion Engines

The internal combustion engine (ICE) has been the ‘silver bullet’ in powering machinery for the transportation, mining and construction industries. However, with existing and upcoming regulations on CO2 emissions, the industry is exploring the viability of fuelling ICEs with hydrogen as a carbon neutral alternative – notable examples include BMW, Toyota, Yamaha (now also rotary ICEs) and JCB.

Current hydrogen combustion research focuses on achieving high brake thermal efficiency (≥45%) while keeping NOx emissions levels low by utilising direct injection fuelling strategies. This results in increased volumetric efficiency and allows for a more precise control of abnormal combustion events compared to port fuel injection. Nevertheless, topics such as combustion irregularities, turbocharger design for hydrogen-specific operation, heat transfer and injection strategy optimisation remain underresearched.

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