Reactivity Controlled Compression Ignition Combustion Systems
Summary
Reactivity Controlled Compression Ignition (RCCI) represents a low-temperature combustion concept that combines two fuels of differing chemical reactivity to achieve precise control over in-cylinder heat release. In an RCCI system, a low-reactivity fuel is premixed with intake air, while a high-reactivity fuel is directly injected into the combustion chamber. The resulting reactivity stratification delays auto-ignition until optimal thermodynamic conditions are reached, promoting a more uniform burn and reducing peak temperatures. This approach yields significant reductions in nitrogen oxides and soot without compromising thermal efficiency, and it offers flexibility in fuel choice, including biofuels and gaseous fuels. Key parameters such as injection timing, fuel share, intake temperature and exhaust gas recirculation rate interact to shape ignition delay and heat release rate. RCCI research spans passenger cars, heavy-duty engines and marine applications, underlining its global importance in meeting stringent emissions regulations and curbing CO₂ output. Progress in optical diagnostics, numerical modelling and prototype demonstrations continues to refine RCCI performance, paving the way for cleaner, more efficient internal combustion systems.
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Reactivity Controlled Compression Ignition Combustion Systems publication trend
The graph below shows the total number of articles in reactivity controlled compression ignition combustion systems across all publications each year (not limited to Nature Index journals).
Technical terms
Reactivity Controlled Compression Ignition (RCCI): A combustion strategy employing two fuels of differing auto-ignition tendencies to achieve stratified reactivity and controlled heat release.
Reactivity stratification: Spatial variation in fuel–air reactivity within the combustion chamber, enabling modulation of ignition timing and burn rate.
Ignition Delay (ID): The time interval between the start of fuel injection and the onset of auto-ignition.
Heat Release Rate (HRR): The rate at which energy is liberated during combustion, influencing efficiency and emissions.
Port Fuel Injection (PFI): A method where a low-reactivity fuel is introduced into the intake port to premix with air before compression.
References
- Optical spray investigation and numerical spray model calibration for the RCCI combustion mode with ethanol/CNG and diesel fuel. Energy Conversion and Management (2024).
- Experimental study of triple fuel physiognomies on LDRCCI diesel engine combustion. Results in Engineering (2023).
- Start of Injection Influence on In-Cylinder Fuel Distribution, Engine Performance and Emission Characteristic in a RCCI Marine Engine. Energies (2024).
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