Rancang Bangun Knalpot Pada Kendaraan Hemat Energi “Tunas” Sebagai Pereduksi Emisi

Motor vehicle exhaust emissions are the result of the fuel combustion process in vehicle engines, producing various pollutants that are harmful to the environment and human health. These pollutants include carbon monoxide (CO) and hydrocarbons (HC). The Mechanical Engineering Department of Politeknik Negeri Bengkalis is currently designing and building an energy-efficient vehicle as part of an environmentally friendly technology development program, which is also aimed at participating in a national-level energy-efficient vehicle competition. During the design process, an issue arose regarding the exhaust system, where the factory-standard exhaust did not match the dimensions of the designed vehicle body and still had the potential to be optimized to produce lower exhaust emissions. This study aims to design and manufacture an exhaust system for the "Tunas" energy-efficient vehicle to reduce CO and HC emissions, as well as to adjust the exhaust design to fit the body of the energy-efficient vehicle. The methodology applied includes a literature study related to exhaust system design, catalytic converter selection, exhaust dimension calculation, and physical design based on the spatial requirements and structure of the "Tunas" vehicle. Emission testing was conducted using a gas analyzer at an engine speed of 1500 rpm with Pertamax Turbo fuel. The results showed that the custom exhaust was able to reduce CO emissions from 0.65% to 0.58% (a reduction of 10.77%) and HC emissions from 671 ppm to 501 ppm (a reduction of 25.34%) compared to the standard exhaust. From the results of this study, it can be concluded that the use of a custom exhaust is able to reduce exhaust emissions from the energy-efficient vehicle.