FlexDI – Hydrogen
Many new technologies are emerging for Hydrogen production, storage and distribution. Vehicle technologies are becoming available for the provision of Hydrogen as a transport energy source. Infrastructure solutions are becoming a reality. Hydrogen is heralded as the fuel of the future offering the possibility of a sustainable and renewable carbon free energy source for transportation. Hydrogen fuel cells are yet to become a production feasible solution due to cost, power density and the need for very pure hydrogen. Fuel-cells are currently of limited use as they are unable to run on any fuel except hydrogen.
Current Hydrogen IC engines all produce NOx and have serious issues with burn-rate control due to the very high speed of Hydrogen combustion. This means that high dilutions and low power densities are unavoidable. The only control to date for combustion problems and NOx production is to operate engines at lean air fuel ratios. Lean operation reduces specific power.
FlexDI can be used to inject Hydrogen directly into the cylinders and will offer a low cost, robust solution for this fuel type. FlexDI enables richer mixtures to be operated without risk of engine backfire and with no displacement of intake air. Direct hydrogen injection can improve engine performance. FlexDI offers superior Hydrogen combustion leading to low exhaust gas after treatment costs.
FlexDI offers a unique solution for Hydrogen combustion. Dual injectors mean that both Hydrogen and water can be direct-injected in the same spray. This gives full control over burn-rates, NOx emissions and provides the ability to run Lambda=1 at high load conditions. This means the reality of high power density is realised with specific outputs the same as, or better than Gasoline (up to 117% of Gasoline).
Engine redesign is not necessary to use Hydrogen fuel with FlexDI systems. Changes to typical FlexDI Gasoline injection systems and optimisation of the compression ratio are required.
FlexDI offers:
- Same or better power density as Gasoline
- Very low NOx production
- High engine efficiency
- Simple after treatment
- True Lambda=1 combustion
- High performance boosted applications
- CO2 free IC engine operation
