Air intake system optimization through velocity stack and turbo cyclone variations for fuel efficiency improvement and exhaust emission reduction in 125cc automatic motorcycles
Keywords:
Air intake optimization, Engine thermal efficiency, Air fuel mixture homogenization, Vehicle pollutant reduction, Resource efficiency, Environmental footprintAbstract
This research aims to analyze the effect of velocity stack and turbo cyclone variations on fuel consumption and exhaust emissions in 125cc automatic motorcycles. The increasing number of motor vehicles in Indonesia has caused significant fuel consumption and air pollution, necessitating technological solutions to improve engine combustion efficiency. The research method used was experimental testing on a Honda Vario 125cc in standard conditions compared with the installation of velocity stack, turbo cyclone, and their combination. Fuel consumption measurement is conducted using the fuel-to-fuel method while exhaust emission measurement includes carbon monoxide and hydrocarbon levels using a gas analyzer at six engine speed levels (idle, 2500, 3500, 4500, 5500, and 6500 rpm). The results showed that the VS1+TC2 combination provided the highest average fuel consumption reduction of 53.71% compared to standard conditions, with exceptional performance at 3500 rpm (61.42% reduction). For exhaust emissions, TC2 alone achieved 18.37% average carbon monoxide reduction across all RPM conditions, with exceptional effectiveness at 3500 rpm where CO was reduced from 0.51 to 0.40 (81.82% reduction). The VS2+TC2 combination provided the most significant hydrocarbon emission reduction, achieving 49.58% average reduction across all test conditions, with strong performance at idle (56.33%), 2500 rpm (43.62%), and 4500 rpm (57.65%). The VS2+TC2 combination was identified as the optimal solution as it provides the best balance with 50.55% fuel consumption reduction, 16.33% carbon monoxide emission reduction, and 49.58% hydrocarbon emission reduction while maintaining effectiveness across the complete RPM range. These findings demonstrate that air intake system optimization is an effective solution to improve resource efficiency while reducing environmental impact in the conventional transportation sector.
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