A Comparison Study of Engine Performance in Range Extended Electric Vehicle and Conventional Vehicle

This study aimed to compare the fuel consumption and performance of engine in range extended electric vehicle (REEV) and conventional vehicle which contain different drive systems. For this purpose, a vehicle system simulation has been used to simulate these vehicle models. This simulation used data from 4 cylinders 1186 cc engine in a conventional vehicle and electric machine, battery, generator and engine 2 cylinders 999 cc in range extended electric vehicle. While aspects of vehicle dimensions such as wheels, brakes, differential, and transmission likened to both drive systems. The results of this simulation have been shown and compared with each other

CFD study several injection timing on homogeneous charge compression ignition hydrogen diesel dual fuels

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

Review of Improving the NOx Conversion Efficiency in Various Diesel Engines fitted with SCR System Technology

The diesel engine is utilized in most commercial vehicles to carry items from various firms; nevertheless, diesel engines emit massive amounts of nitrogen oxides (NOx) which are harmful to human health. A typical approach for reducing NOx emissions from diesel engines is the selective catalytic reduction (SCR) system; however, several reasons make reducing NOx emissions a challenge: urea particles frequently become solid in the injector and difficult to disseminate across the system; the injector frequently struggles to spray the smaller particles of urea; the larger urea particles from the injector readily cling to the system; it is also difficult to evaporate urea droplets because of the exhaust and wall temperatures (Tw), resulting in an increase in solid deposits in the system, uncontrolled ammonia water solution injection, and NOx emissions problems. The light-duty diesel engine (LDD), medium-duty diesel engine (MDD), heavy-duty diesel engine (HDD), and marine diesel engine use different treatments to optimize NOx conversion efficiency in the SCR system. This review analyzes several studies in the literature which aim to increase NOx conversion in different diesel engine types. The approach and methods demonstrated in this study provide a suitable starting point for future research into reducing NOx emissions from diesel engines, particularly for engines with comparable specifications

A study effects of injection pressure and wall temperature on the mixing process of NOx and NH3 in Selective Catalytic Reduction system

Diesel engines are commonly used for public transportation on-road and off-road applications. Growth production of the diesel engine is very significant from year to year. Nitride Oxide (NOx) from diesel engine was one of the major sources of air pollution. Selective Catalytic Reduction (SCR) has been successfully used to reduce NOx from a diesel engine with a chemical reaction from ammonia (NH3). The mixing reaction between NOx and NH3 reaction can produce steam (H2O) and Nitrogen (N2). However, ammonia uniformity pattern usually not homogenization and the ammonia was difficult to mix with NOx. The constant air flows incomplete to assist the spray injector to spread NH3 to all corners of SCR. The impact study of turbulent phenomena and standard k-epsilon Low-Reynolds Number model to the mixing process in the SCR system using STARCCM+. The simulation studies are conducted under different pressure (4 to 6 bars), the injection rate (0.04 g/s) and temperature (338 K – 553 K) and the high pressure and high velocity magnitude creating turbulent swirl flow. The ammonia decomposition process and mixing process with NOx were investigated using a box with optical access. The simulation and numerical study results validated using back pressure value and the distribution of NOx concentration value from the catalyst outlet. The wall temperature will increase the urea evaporation to generate ammonia and gas pressure will increase the mixing process and chemical process in the SCR system. These reactions enable to optimize the SCR system technology which eventually able to reduce the NOx quantity from a diesel engine

Investigation of Urea Uniformity with Different Types of Urea Injectors in an SCR System

Heavy-duty diesel engines in highway use account for more than 40% of total particulate and nitrogen oxide (NOx) emissions around the world. Selective catalytic reduction (SCR) is a method with effective results to reduce this problem. This research deals with problems in the urea evaporation process and ammonia gas distribution in an SCR system. The studied system used two types of urea injectors to elucidate the quality of ammonia uniformity in the SCR system, and a 12,000-cc heavy-duty diesel engine was used for experimentation to reduce NOx in the system. The uniformity of the generated quantities of ammonia was sampled at the catalyst inlet using a gas sensor. The ammonia samples from the two types of urea injectors were compared in experimental and simulation results, where the simulation conditions were based on experimental parameters and were performed using the commercial CFD (computational fluid dynamics) code of STAR-CCM+. This study produces temperatures of 371 to 374 °C to assist the vaporization phenomena of two injectors, the gas pattern informs the distributions of ammonia in the system, and the high ammonia quantity from the I-type urea injector and high quality of ammonia uniformity from the L-type urea injector can produce different results for NOx reduction efficiency quality after the catalyst process. The investigations showed the performance of two types of injectors and catalysts in the SCR system in a heavy-duty diesel engine

Thermal efficiency and emission characteristics of a diesel-hydrogen dual fuel CI engine at various loads condition

Efforts to find alternative fuels and reduce emissions of CI engines have been conducted, one of which is the use of diesel hydrogen dual fuel. One of the goals of using hydrogen in dual-fuel combustion systems is to reduce particulate emissions and increase engine power. This study investigates the thermal efficiency and emission characteristics of a diesel-hydrogen dual fuel CI engine at various loads condition. The hydrogen was used as a secondary fuel in a single cylinder 667 cm3 diesel engine. The hydrogen was supplied to intake manifold by fumigation method, and diesel was injected directly into the combustion chamber. The results show that the performance test yielding an increase around 10% in the value of thermal efficiency of diesel engines with the addition of hydrogen either at 2000 or 2500 rpm. Meanwhile, emission analyses show that the addition of hydrogen at 2000 and 2500 rpm lead to the decrease of NOx value up to 43%. Furthermore, the smokeless emissions around 0% per kWh were occurred by hydrogen addition at 2000 and 2500 rpm of engine speeds with load operation under 20 Nm