Sequential combustion process on diesel dual fuel engine with compressed natural gas (CNG) fuel was complex. The problems of diesel dual fuel with CNG gas are reduced thermal efficiency and resulting in high carbon monoxide (CO) and unburned hydrocarbon (HC) emissions. The right setting between combustion air, diesel pilot fuel, and CNG gas fuel can improvement the performance and emissions. The experiment was conducted with diesel fuel conventional and dual fuel mode with CNG fuel in a single cylinder, four strokes, constant speed (1500 rpm) diesel engine type diamond DI 800. Performance parameters such as thermal efficiency and specific fuel consumption (SFC), emissions such as CO, HC, and smoke density are determined at five starts of injection timing (SOI) CNG of 70 0 CA, 90 0 CA, 110 0 CA, 130 0 CA, dan 150 0 CA ATDC with ECU programmable of Vemstune software. The results indicated that retarded CNG injection timings improved engine performance and emissions diesel dual fuel. Start of CNG injection timing optimization at 130 0 CA ATDC with increased thermal efficiency 14,35% and decreased specific fuel consumption (SFC) 8,83 % . in addition, it decreased CO emissions 21,35%, HC emissions 17,93%, and PM emissions lower 34,98%. However, engine performance diesel dual fuel lower than a conventional diesel engine.

The use of diesel engines in commercial vehicles is still the main choice and the most widely used. The increasing number of commercial vehicles that use diesel engines can pollute the environment and cause noise. In order to reduce exhaust emissions and noise in diesel engines, a particulate filter diesel technology was created which is installed in commercial vehicle diesel engines. This study uses an experimental method. The test was carried out on a Mitsubishi L300 commercial vehicle diesel engine type 4D56 4 cylinder with a cylinder capacity of 2477 cc. The diesel particulate filter technology uses a half honeycomb model made from galvalume plates, with variations in the addition of filters in the form of glass wool of 50 grams, 100 grams, 150 grams, 200 grams, and 250 grams. Testing the exhaust emissions of a diesel engine using a TEN Automotive Equipment Innova 2000 multigas analyzer with a smoketester. Sound noise testing using a sound level meter test tool LT Lutron SL-4001. The test results with the addition of diesel particulate filter technology can reduce exhaust emissions and sound noise. The use of diesel particulate filter technology can reduce exhaust emissions in the form of Particulate Matter (PM) most optimally at the addition of a 100 gram filter with a decrease of 45.9%. The most optimal reduction in noise is the addition of a 50 gram filter with a decrease of 26.5%.

Bus yang dimiliki oleh perusahaan harus mampu memberikan performa yang optimal dan dapat memberikan keuntungan bagi perusahaan. Hal tersebut dapat dilihat dari salah satu komponen kendaraan tersebut yaitu ban. Penelitian ini bertujuan untuk mencari besaran rolling resistance pada tiap variasi tekanan ban dan pengaruhnya terhadap konsumsi bahan bakar. Untuk mencari besaran rolling resistance pada tiap variasi tekanan ban, peneliti melakukan eksperimen tentang metode coast down. Pada tahap perhitungan konsumsi bahan bakar setiap variasi tekanan ban menggunakan metode kuantitatif. Hasil penelitian ini menunjukkan bahwa adanya pengaruh tekanan ban terhadap konsumsi bahan bakar pada kendaraan bus Isuzu. Pada tekanan ban depan 68 psi dan belakang 85 psi menghasilkan gaya Rr 769,692 N dengan konsumsi bahan bakar 304,622 liter/tahun. Pada tekanan 58 psi dan 75 psi gaya Rr sebesar 874,650 N dengan konsumsi bahan bakar 346,161 liter/tahun. Tekanan 48 dan 65 psi menghasilkan gaya Rr 973,643 N dengan konsumsi bahan bakar 385,340 liter/tahun. Pada tekanan 38 psi dan 55 psi gaya Rr sebesar 1.066,293 N dan konsumsi bahan bakar 422,008 liter/tahun. Semakin turun tekanan ban, semakin besar gaya rolling resistance dan konsumsi bahan bakar semakin meningkat.

Inspection railway are a re-design of railway that have been made in the Indonesian Railway Polytechnic. Inspection lorry repairs are carried out on the wheels, chassis, drive and body.The new lorry wheels are made of structural iron to reduce the total weight from 148 kg to 119 kg. The size of the wheel conus is the difference between the outer and inner diameter of 30 mm to minimize wheel friction with rails in the curved region. The chassis uses the ledder frame model with emphasis on the strength of 44.29 MPa and 0.095 MPa deflection to get optimal and reliable results on the 1067 track. The material uses galvanized hollow type iron weighing 125 kg. The environmentally friendly drive used in the railway inspection is an BLDC electric motor (brushless direct current) with a capacity of 2000 watts of power, a current of 35A and a rotational speed of 4250 Rpm. The railway inspection body is made of 3 layers fiber reinforced polymers of plastics (FRP) using a hand lay-up method that has a tensile stress value of 40.18 MPa and a strain value of 0.89%. The inspection body focuses on the aesthetics and ergonomics aspects in the form of a more attractive appearance, smoothness of design, passenger comfort and color harmony so that they have high selling.

The purpose of this study was to determine the effect of variations in electrical piezo size and train locomotive noise to the voltage generated using ANSYS. Pezoelectric Size variations used are 1x1, 3x3, 5x5 (cm). As for the noise variations used are 93, 96, 98, 100 (dB). The method used is the numerical method; in this case Finite Element Analysis (FEA) with the help of ANSYS Static structural program. The results showed that using piezoelectric 5x5 cm and at 100 dB noise produced a maximum voltage of 158.12 mV.