Influence of the stop/start system on CO2 emissions of a diesel vehicle in urban traffic

This paper presents measurements of CO2 emission and efficiency of stop/start technology on a diesel vehicle in urban traffic. Two four-wheel-drive diesel vehicles with on-board exhaust emission and vehicle activity measurement systems were tested in two urban driving circuits representative of downtown Madrid. The vehicles had similar turbocharged and intercooled diesel engines fulfilling the same Euro 4 emissions regulation; but one had an improved engine incorporating stop/start technology. CO2 emission reduction of more than 20% for the car equipped with the stop/start system was obtained. Regardless of the variability in driving style, the grade and type of streets, traffic congestion, and the engine operating temperature, the car equipped with the stop/start system has intrinsically a lower CO2 emission factor

Effects of fuel ratio on performance and emission of diesel-compressed natural gas (CNG) dual fuel engine

Recent research breakthrough reveals that diesel-CNG dual fuel (DDF) combustion can potentially reduce exhaust emission of internal combustion engines. However, problem arises when knock phenomenon occurs producing high carbon monoxide (CO) and hydrocarbon (HC) emission due to uncontrolled blending ratio of diesel-CNG fuel on specific engine load. This study will determine the limit of dual fuel ratio before knock occurrence while analysing performance and exhaust emission of an engine operating with diesel and DDF fuel mode. A 2.5 litre 4-cylinder direct injection common-rail diesel engine was utilised as a test platform. The modelstested were 100% Diesel, 90% DDF, 80% DDF and 70% DDF, representing diesel to CNG mass ratio of 100:0, 90:10, 80:20 and 70:30 respectively. It was found that DDF engine performance was lower compared to diesel engine at 1500 rpm engine speed. At higher engine speed, the 70% DDF showed engine performance comparable to diesel engine. However, high HC emission with knock onset and a decrease of Nitrogen Oxide (NOX) emission were recorded. This study suggests the preferred limit of dual fuel ratio should not be lower than 70% DDF which will be able to operate at high engine speed without the occurrence of knock and poor exhaust emission

Characterising the friction and wear between the piston ring and cylinder liner based on acoustic emission analysis

In this paper, an experimental investigation was carried out to evaluate the friction and wear between the cylinder liner and piston ring using acoustic emission (AE) technology. Based on a typical compression ignition (CI) diesel engine, four types of alternative fuels (Fischer-Tropsch fuel, methanol-diesel, emulsified diesel and standard diesel) were tested under dif-ferent operating conditions. AE signals collected from the cylinder block of the testing en-gine. In the meantime, the AE signals in one engine cycle are further segregated into small segments to eliminate the effects of valve events on friction events of cylinder liner. In this way, the resulted AE signals are consistent with the prediction of hydrodynamic lubrication processes. Test results show that there are clear evidences of high AE deviations between dif-ferent fuels. In particular, the methanol-diesel blended fuel produces higher AE energy, which indicates there are more wear between the piston ring and cylinder liner than using standard diesel. On the other hand, the other two alternative fuels have been found little dif-ferences in AE signal from the normal diesel. This paper has shown that AE analysis is an ef-fective technique for on-line assessment of engine friction and wear, which provides a novel approach to support the development of new engine fuels and new lubricants

Behavior of a CI Engine Running by Biodiesel under Transient Conditions

The emission characteristics of compression ignition (CI) engines running on biodiesel during transient operating conditions, which is the most usual case in urban and extra-urban transportation, have rarely been investigated. In the present study an experimental investigation on emission characteristics of a CI engine has been carried out both under steady state and transient operating conditions. The experimental work has been carried out on CI engine, which is integrated with transient testing facility. This facility is capable of varying the engine speed and load over a given time period. To measure the engine emissions, an emission analyser has been used to measure CO2, CO, THC, and NOx emissions. The fuels used in the analyses are 25% (25B) and 100% (100B) of biodiesel blend and diesel. The series of the transient events studied are speed changes from 900 to 1200rpm, 1200 to 1500rpm and 1500 to 1800rpm over a time period of 4 seconds each. These tests were performed at a constant load of 105Nm, 210Nm, 315Nm and 420Nm. The transient test results have shown that the emissions of CI engine running on biodiesel were reduced by up to 17%, 52% and 38% for CO, CO2 and THC emissions respectively as compared to diesel fuel. However, the NOx emission was seen to be 17% higher for engine running on biodiesel than that on diesel during transient conditions

Penggunaan Minyak Nabati Sebagai Bahan Bakar Alternatif Pada Motor Diesel Sistim Injeksi Langsung

Vegetable oil as an example product of agricultural engineering, has potential to be developed to renewable energy called bio-diesel. This paper describes comparison study performance from a direct injection system diesel-engine fueled with composition 20%, 30% and 40% bio-diesel, with diesel engine fueled diesel oil (solar). The test results have shown that the engine fueled with 20%, 30%, and 40% bio-diesel produce slightly lower torque and power than the same engine fueled with solar. The other research before, the emission test results have shown a lower particulate matter, hydrocarbon and carbon monoxide from exhaust

Energy consumption and emissions of diesel-CNG dual fuel engine at high load operation

Global warming and energy sustainability issues are among the major world concern. Malaysian National Green Technology Policy 2009 and Thailand Power Development Plan 2015-2036 (PDP 2015) were launched to enhance the green and sustainable energy usage. Meanwhile in the transportation sector, National Automotive Policy (NAP) has been implemented and revised to enhance the usage of the green energy, in order to achieve a low carbon emission and energy efficient vehicle. Researchers keep striving to find alternative solutions to power vehicles by cleaner energy efficiently. Compressed Natural Gas (CNG) has lower carbon emission and higher energy density compared to common petroleum fuel. It provides an opportunity to power the vehicle cleanly. Thus, it has been used as an alternative for fueling gasoline engine. However, CNG fuel is difficult to be applied on diesel engine. Unlike gasoline engine, diesel engine does not have spark plug and its fuel is combusted through compression in cylinder. Since CNG has high octane number, it is difficult to self-ignite in diesel engine. Therefore, Diesel-CNG Dual Fuel (DDF) system is applied. The system use CNG as part fuel and certain amount of diesel pilot fuel is injected into the cylinder to ignite the combustion. DDF engine may potentially reduce Carbon Dioxide (CO2) emission. However, high fuel consumption and Nitrogen Oxide (NOX) emission have been observed at high load engine operation due to improper fuel ratio. In this study, four ratios of DDF were tested and compared with 100% diesel: 90D10G, 80D20G, 70D30G, 60D40G. It was found that each of the fuel ratio behaved differently in terms of brake specific energy consumption (BSEC) and exhaust emissions

Experimental investigation into the effect of magnetic fuel reforming on diesel combustion and emissions running on wheat germ and pine oil

© 2019 Elsevier B.V. All rights reserved.The present study aims to explore the effect of fuel ionisation on engine performance, emission and combustion characteristics of a twin cylinder compression ignition (CI) engine running on biofuel. Wheat germ oil (WGO) and pine oil (PO) have been identified as diesel fuel surrogates with high and low viscosities, respectively. High viscosity biofuels result in incomplete combustion due to poor atomisation and evaporation which ultimately leads to insufficient air-fuel mixing to form a combustible mixture. Consequently, engines running on this type of fuel suffer from lower brake thermal efficiency (BTE) and higher soot emission. In contrast, low viscosity biofuels exhibit superior combustion characteristics however they have a low cetane number which causes longer ignition delay and therefore higher NO emission. To overcome the limitations of both fuels, a fuel ionisation filter (FIF) with a permanent magnet is installed upstream of the fuel pump which electrochemically ionises the fuel molecules and aids in quick dispersion of the ions. The engine used in this investigation is a twin cylinder tractor engine that runs at a constant speed of 1500 rpm. The engine was initially run on diesel to warm-up before switching to WGO and PO, this was mainly due to poor cold start performance characteristics of both fuels. At 100% load, BTE for WGO is reduced by 4% compared to diesel and improved by 7% with FIF. In contrast, BTE for PO is 4% higher compared to diesel, however, FIF has minimal effect on BTE when running on PO. Although, smoke, HC and CO emissions were higher for WGO compared to diesel, they were lower with FIF due to improved combustion. These emissions were consistently lower for PO due to superior combustion performance, mainly attributed to low viscosity of the fuel. However, NO emission for PO (1610 ppm) is higher compared to diesel (1580 ppm) at 100% load and reduced with FIF (1415 ppm). NO emission is reduced by approximately 12% for PO+FIF compared to PO. The results suggest that FIF has the potential to improve diesel combustion performance and reduce NO emission produced by CI engines running on high and low viscosity biofuels, respectively.Peer reviewe

Uji Prestasi dan Emisi Diesel Berbahan Bakar Minyak Nabati Murni untuk Pembangkitan Daya di Daerah Terpencil

Pure Plant Oil (PPO) such as Pure Coconut Oil (PCO) and Pure Palm Oil (PPaO) could be a solution for electricity problem in remote areas in Indonesia. PCO and PPaO can be used as a fuel for diesel engine to produce electricity. This paper will compare and analyze the performance and emissions of the diesel power plant fueled with diesel fuel, PCO, and PPaO. For performance parameter, brake specific fuel consumption and thermal efficiency of diesel engine by using PPaO and PCO are higher than the diesel fuel, but the brake specific energy consumption are lower than the diesel fuel. That means diesel engine will be more efficient and have lower operational cost by using PPaO and PCO. For the emission parameters, CO2, CO, and CH emissions from PPaO and PCO are higher compared to diesel fuel. That means PPO have higher carbon emission than just using conventional diesel fuel. But, there are highly significant difference of less NOX emissions by using PCO and PPaO compared to the diesel fuel. That means it will be better using PPO because diesel engine has lack of high NOX emissions. These differences of diesel engine performance and emissions by PPaO, PCO, and diesel fuel are caused by the fuel characteristic differences such as cetane number, calorific value, and viscosity

Performance and emissions of compression ignition engine fueled with preheated blend of vegetable oil

Now days fossil fuel has been a problem that can been use in a compression ignition engine. Straight vegetable oil is one of the most reliable fuel that suitable for diesel engine. The scope of study of this study is focused on performance and emission of the straight vegetable oil from the grocery store to compare with crude palm oil from UTHM pilot plan. S5, S10 and S15 straight vegetable oil fuel is used for this experiment. This straight vegetable oil is also compared with an natural diesel in a combustion-ignition engine. The test is conducted with UTHM dynomometer which is located at automotive lab. The properties of the vegetable oil is tested for density, kinematic viscosity, water content, acids value and flash points. Brake power, flywheel torque, (in term of hydrocarbon, carbon monoxide, carbon dioxide, oxygen content and smoke opacity) and tested for performance and emission. Results obtained show that flywheel torque that has been produced from the biodiesel fuels are less than the natural diesel (ND). Biodiesel emission results shown a better emission compared to the ND fuels. The CO2, CO, HC and O2 content that released from the biodiesel fuels are clearly lower than the ND fuels. At low engine speed, biodiesel smoke opacity contents are quite high produces compared to the OD and other type o