| dc.description.abstract | The use of fossil fuels, especially crude oil, as a primary source of energy has led to a significant decline in fossil energy reserves and has had a major impact on the transportation sector. Many countries, including Indonesia, are conducting research to enhance fuel efficiency to address the global energy crisis. The Horas USU Team has developed methods to improve diesel engine performance, such as increasing the thickness of shim nozzles on pressure springs to strengthen the weakened pressure spring force and reduce spring inertia, and enhancing combustion efficiency inside the engine cylinder. This research aims to analyze the performance of the diesel engine in the Urban Diesel Team Horas USU vehicle. Parameters tested include nozzle pressure, torque, power, air-fuel ratio, specific fuel consumption, thermal efficiency, mean effective pressure, and exhaust gas emissions. The maximum nozzle pressure measured with a nozzle tester was 200 kg/cm2 using a 0.7 mm thick Shim Nozzle component. The maximum torque from dyno testing reached 7.2 Nm at 2700 rpm using a 0.7 mm thick Shim Nozzle component. The maximum power from dyno testing was 2 kW at 2700 rpm using a 0.7 mm thick Shim Nozzle component. The maximum air-fuel ratio from dyno testing was 20.729 at 3340 rpm. The lowest specific fuel consumption from testing was 250.79 g/kWh using a 0.7 mm thick Shim Nozzle component. The maximum thermal efficiency in testing reached 31.45% at 2700 rpm using a 0.7 mm thick Shim Nozzle component. The highest mean effective pressure reached 4.6203 kg/cm2 at 2700 rpm using a 0.7 mm thick shim nozzle. The thickness of the shim also affects changes in exhaust gas emission levels | en_US |
