Performance and Emission Characteristics of Reactivity Controlled Compression Ignition (RCCI) Engine with Diesel-Butanol and Gasoline Blends

Abstract

Reactivity Controlled Compression Ignition, or RCCI, combustion in internal combustion engines offers a practical way to reduce emissions and increase fuel efficiency. This study investigates the environmental impacts of RCCI combustion using Indian fuel combined with butanol biodiesel. Through intensive testing and analysis, the study assesses the emissions performance, combustion characteristics, and environmental impacts of this novel fuel blend. The results demonstrate a notable decrease in particulate matter, greenhouse gas emissions, and other dangerous pollutants when compared to conventional diesel combustion. Additionally, butanol biodiesel, which is produced from sustainable feedstocks, has the potential to lessen the harm that conventional fossil fuels cause to the environment. The findings suggest that burning RCCI with Indian fuel and butanol biodiesel could encourage a more sustainable and ecologically friendly transportation sector, which would support environmental conservation initiatives.

Introduction

RCCI engines are an emerging technology aimed at improving thermal efficiency and reducing harmful emissions (NOx and particulate matter) in internal combustion engines. Their success depends on suitable alternative fuels like butanol—a four-carbon alcohol with favorable properties such as high energy density and compatibility with existing fuel infrastructure.

The study uses a variable compression ratio (VCR) single-cylinder diesel engine equipped with an eddy current dynamometer to test different butanol-biodiesel fuel blends. The setup includes advanced instrumentation for monitoring combustion parameters, airflow, fuel flow, and emissions.

The methodology to reduce emissions involves optimizing fuel selection, injector timing, intake air conditions, and valve timing.

Key results:

• Brake Thermal Efficiency (BTE) increases with load; blend B15 shows the highest efficiency.

• Brake Specific Fuel Consumption (BSFC) decreases with load; B15 exhibits the best fuel economy.

• Brake Power improves with higher blend ratios; B10 shows balanced performance, while B15 peaks at high load.

• Emissions: B5 blend yields the lowest CO emissions, while B20 shows reduced CO2 emissions but higher hydrocarbons (HC). B5 and B10 blends effectively reduce HC emissions.

• Exhaust Gas Temperature decreases as blend concentration increases, indicating potentially more efficient combustion.

Overall, butanol-biodiesel blends, especially B5 to B15, improve engine performance and reduce emissions, making them promising alternatives for RCCI engines.

Conclusion

The current experimental research project includes the characterization, performance, combustion, and emissions characteristics of RCCI engines that are powered by biodiesel blends. The results of the study were summarized as follows: 1) B15 enhances engine performance metrics, such as brake thermal efficiency, in comparison to diesel. This happened because of the fuel\'s inherent oxygen content, which makes fuels burn all the way through. 2) When compared to diesel, brake power rises with B15 while BSFC falls. 3) Emissions of hydrocarbons (HC) and carbon monoxide (CO) drop when B10 and diesel are compared at 3.71 kW brake power. 4) Compared to diesel, B20 lowered C02 emissions at 3.61 kW of brake power. 5) Compared to diesel, B20\'s brake power of 3.67 kW decreased CO2 emissions. 6) The exhaust gas temperature of the B20 is lower than that of the diesel. Butanol biodiesel blends are a viable fuel substitute for RCCI engines with respectable combustion, emission, and performance characteristics, according to the discussions above. Blends of butanol biodiesel may therefore be a suitable alternative to fossil diesel fuel. Taking everything into account, B15 seems to be a superior alternative fuel choice.

References

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Copyright

Copyright © 2025 Prof. Shrikrishna R. Wagh, Mr. Kiran Kokate, Mr. Mithilesh Zalke , Ms. Vaibhavi Bopale, Mr. Dovesh Aglawe, Mr. Prasad Saraf , Mr. Parth Tirmare. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.