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A study on combustion of range extender spark ignition engine fueled with biogas was conducted using a simulation method in BOOST AVL software. The study was conducted using a two cylinders range extender based spark ignition engine for 35 kW of an electric vehicle fueled with gasoline-biogas mixed varied from 0 to 100% by volume. The biogas fuel in this study is represented as high purity biogas after purifying process which mainly contains CH4 or methane. The engine was operate on 3500 rpm and biogas was fumigated into the intake manifold. The results showed that the highest incylinder pressure obtained from engine fueled with 80% biogas. Meanwhile, the lowest in-cylinder temperature resulted from the engine fueled with 100% of biogas. Finally, the emission of CO and HC increase with the increases of biogas content, while the NOx is decrease when the biogas content increases.

Conventional diesel engine have a problem with exhaust gas emission where there is a trade of NOx and soot formation inhibits with emission regulation. For this problem, this paper explores the effect of volatility of fuel in on performance and emission in diesel engine. Diesel fuel was blended with N heptane as a volatility fuel into different massbased fraction (0%, 20 %, 40%, 60%, 80%). Thermodynamic Boost AVL simulation software under two engine load condition (10 Nm and 50 Nm) were simulated at 2200 rpm. The model of the engine using Yanmar TF 155 with 102 x 105 bore and stroke with 17,8 compression ratios. The start of combustion was fixed at 5°CA BTDC with 80-degree combustion duration for all test cases. Pressure in the combustion chamber shows a decrease of up to 15 percent for loads between 10 Nm to 50 Nm loads. The addition of volatility of the fuel indicates the atomization of the fuel and the process of mixing the fuel changes during the ignition delay process. Rate of heat release shows a decrease of up to 7 percent for loads between 10 Nm to 50 Nm loads. In the case of the volatility fuel of diesel/normal heptane, the rate of heat release (ROHR) shows that the higher volatility produced lower and faster than a mixture with less volatility. The high-volatility fuel has effect on NOx and soot emissions. At 10 Nm load and 80% Normal Heptane, the NOx concentration decreased 40 %. While running under 50 Nm load and 80% of Normal Heptane, the NOx concentration decreased 14 %. This is a advantaged of replacing the volatility fuel-air mixture causing a reduction in the heating value of air and fuel. Raising the load increases soot concentration.

Among the alternative fuels, hydrogen shows great potential as fuel and energy carrier. Hydrogen fuel is a renewable fuel with low emissions, odourless, non-toxic and has a wide align flammability in internal combustion engine. The combination between hydrogen diesel dual fuels with Homogeneous Charges Compression Ignition (HCCI) as a new combustion technology was observed in this paper. One of the problems of HCCI is combustion auto ignition control of the mixture of fuel used and the high heat release produced. In recent years, several studies about the HCCI method with dual fuel is that it requires new infrastructure to supply two fuels at once to the combustion engine. For this reason, it is endeavored to use multiple fuels into one fuel (using reforming parts) before injecting to internal combustion engine. The results of CFD study several injection timing on HCCI with dual fuel hydrogen diesel fuel, the highest pressure value in the combustion chamber was achieved at 107 bar pressure 360 degrees CA. Whereas by using the conventional method only obtained a pressure of 72 bar 363 degrees CA. In addition, the rate of heat release value with the HCCI method was 127 J / deg. at 10 deg. BTDC, compared to the conventional method which only reaches 32 J / deg. at 1 deg. ATDC. It is clear that there is heat transfer to BTDC before TDC, due to the homogeneity of the fuel in the HCCI method.

Compressed natural gas (CNG) is one of the alternative fuels that has a great potential in the near future. The cyclic variation of a diesel engine combustion fueled with CNG and ignited by pilot fuel with different fuel volatility was investigated and presented in this study. To investigate the combustion characteristics of diesel dual fuel engine, a single cylinder diesel engine has been modified to use CNG as fuel. CNG was fed into the intake manifold by a mixer before entering the combustion chamber. The engine was operated at a constant speed of 1400 rpm and variable loads. An engine indicating system was used to sample and record the engine cylinder pressure for 100 consecutive cycles. The combustion data were then analyzed for the maximum cylinder pressure for each cycle and its derivative parameter (rate of heat release). The cyclic variation is indicated by the mean value, standard deviation, and coefficient of variation of the maximum pressure. In higher engine load operation, the cyclic variability is found to be reduced. In addition, volatile pilot fuel resulted in more stable combustion especially at low load.

The airflow in the engine cylinder is known to greatly affect the performance of the engine. Therefore, the main objective of this study is to evaluate the flow characteristics of the in-cylinder small engine to see the effect of the intake port configuration at equivalent rated engine speed using simulation model under various intake valve lift conditions. Geometry engine created using CAD software, then exported and analyzed using CONVERGE. The turbulence model is observed using a modified model (RNG) k-ɛ. The pressure boundary conditions are used to determine the pressure fluid at the intake and exhaust port. The result shows that the change combination of the intake port give effect to swirl ratio value. The helical intake port with same direction have the highest swirl ratio during intake and compression stroke around thirteen times compare to the original model in valve lift maximum. The change combination of the intake port also give effect to the tumble ratio where the maximum tumble ratio occurs at the helical port with same direction where the maximum increase at 460 °CA around 83 % and the minimum tumble ratio occurs at helical port with opposite direction where the maximum decrease at 460 °CA around 83 %. The change combination of the intake port also give effect to increase the turbulent kinetic energy where the maximum increase around 300 % for model with same direction and 240 % for model with opposite direction and length scale also increase 35 % for model with same direction and 40 % for model with opposite direction. Finally, it is concluding that the analysis carried in this work is useful in predicting the flow and in-turn optimizing combustion chamber of the engine.

This paper reports the comparison of two methods of distance measuring using a digital camera and computing resources namely: Pose from Orthographic Projection and Triangle Similarity. Both methods incorporating a computer vision algorithm to properly functioned. Specifically, this report describes the utilization of such methods for vehicular application, for example, the inter-vehicular distance estimation, hence, to improve safety driving moreover to support the developing Advanced Driver-Assistance Systems ADAS. Each method constructed in an algorithm wrote in Python running in a Raspberry Pi computer equipped with a suitable camera. To process the incoming images, an OpenCV library was tasked to conduct a classification to distinguish vehicle-like features in an image frame from the rest of the universe. Haar cascade classifier was chosen to perform the image features classification. The algorithm then annotates and marks the classified features as a candidate for a vehicle-like object. The classifier was trained by a precompiled dataset. Both methods compared for the best performance on three distance measurement: 10, 15, and 20 meters. With experiment setup, the best distance to measure was 15 meters with small error to the ground truth.

Emission control strategy on GCI engines fueled with 5% by volume of biodiesel blended in gasoline was conducted in this study. The study was conducted using a 1-cylinder DI-CI engine. The engine was fueled with 5% by volume of biodiesel blended in gasoline. GCI combustion with the pilot, and main direct injections were applied in this study. Various EGR rate and intake pressure were also adapted to explore their effects on combustion and exhaust pollution control of the CI engines. It is found that gasoline-biodiesel blend with GCI combustion mode and various parameters especially EGR and intake boosting rate takes effect on the improvement of combustion characteristics which is closely related to HC, CO, NOx, and smoke emissions, respectively.

Numerical methods are used to predict HCCI engine performance, which is more cost-effective than experimentation alone. Specific strategies used numerical methods in HCCI an engine with three-dimensional modelling of combustion on 1 cylinder HCCI combustion engine fuelled by Diesel fuel is described in this paper. The 3 D model is performed on AVL Fire software. The combustion with basic parameters including different start time of Injections (SOI) with the same duration of combustion (BD), indicating pressure in chamber and emissions (Nitric Oxide and soot) were evaluate. The modelling results show that the highest value of pressure in the combustion chamber on the HCCI method was achieved at a pressure of 107 bar 360 deg CA, while in conventional combustion methods it was achieved at 72 bar 363 deg CA. On the other hand the highest peak heat transfer rate is 127 J / deg at 10 deg BTDC, whereas for conventional method occurs at 32 J / deg at 1deg ATDC. So there is a shift of heat transfer toward to BTDC before TDC, due to the already homogeneous fuel in the HCCI method. The combustion process in HCCI engines increases emissions with high NO emissions and reduces Soot emissions.