Performance and Emission Characteristics of Diesel Fuelled Homogeneous Charge Compression Ignition (HCCI) Engine

ABSTRACT: An experimentally investigation is carried out to analysis the performance and emission characteristics of Homogeneous charge compression ignition engine (HCCI). Over the past decades many researcher have been discussed about working of HCCI engine. The HCCI engine is a suitable replacement for compression ignition engine (CI). This paper experimentally investigate the performance and emission characteristics of a HCCI engine at different load with constant speed and compare with convention CI engine. In this research, the HCCI mode engine uses the port fuel injection (PFI) for preparing the homogeneous air-fuel mixture. The results show that the specific fuel consumption is decreased for diesel fuelled HCCI mode engine compared to DI-CI engine. The brake thermal efficiency of HCCI mode engine is even as same or slightly increased. From the result observed that the value of oxides of nitrogen (NOx) and particulate matter (PM) emissions are very low than the DI diesel engine. The rate of reduction of NOx and PM are about 20% and 5% respectively. But the exhaust emission of un burnt hydrocarbon (UHC) and carbon monoxide (CO) are higher than DI mode diesel engine

Biofuels and thermal barrier:a review on compression ignition engine performance, combustion and exhaust gas emission

The performance of an internal combustion engine is affected when renewable biofuels are used instead of fossil fuels in an unmodified engine. Various engine modifications were experimented by the researchers to optimise the biofuels operated engine performance. Thermal barrier coating is one of the techniques used to improve the biofuels operated engine performance and combustion characteristics by reducing the heat loss from the combustion chamber. In this study, engine tests results on performance, combustion and exhaust emission characteristics of the biofuels operated thermal barrier coated engines were collated and reviewed. The results found in the literature were reviewed in three scenarios: (i) uncoated versus coated engine for fossil diesel fuel application, (ii) uncoated versus coated engine for biofuels (and blends) application, and (iii) fossil diesel use on uncoated engine versus biofuel (and blends) use on coated engine. Effects of injection timing, injection pressure and fuel properties on thermal barrier coatings were also discussed. The material type, thickness and properties of the coating materials used by the research community were presented. The effectiveness and durability of the coating layer depends on two key properties: low thermal conductivity and high thermal expansion coefficient. The current study showed that thermal barrier coatings could potentially offset the performance drop due to use of biofuels in the compression ignition engines. Improvements of up to 4.6% in torque, 7.8% in power output, 13.4% in brake specific fuel consumption, 15.4% in brake specific energy consumption and 10.7% in brake thermal efficiency were reported when biofuels or biofuel blends were used in the thermal barrier coated engines as compared to the uncoated engines. In coated engines, peak cylinder pressure and exhaust gas temperature were increased by up to 16.3 bar and 14% respectively as compared to uncoated condition. However, changes in the heat release rates were reported to be between −27% and +13.8% as compared to uncoated standard engine. Reductions of CO, CO2, HC and smoke emissions were reported by up to 3.8%, 11.1%, 90.9% and 63% respectively as compared to uncoated engines. Significant decreases in the PM emissions were also reported due to use of thermal barrier coatings in the combustion chamber. In contrast, at high speed and at high load operation, increase in the CO and CO2 emissions were also reported in coated engines. Coated engines gave higher NOx emissions by about 4–62.9% as compared to uncoated engines. Combined effects of thermal barrier coatings and optimisation of fuel properties and injection parameters produced further performance and emissions advantages compared to only thermal barrier coated engines. Overall, current review study showed that application of thermal barrier coatings in compression ignition engines could be beneficial when biofuels or biofuel blends are used instead of standard fossil diesel. However, more research is needed combining coatings, types of biofuels and other engine modifications to establish a concrete conclusion on the effectiveness of the thermal barrier when biofuels are used in the compression ignition engine. Reduction of NOx emissions is another important R & D area

Effects of

This work investigates the effect of both inlet air temperature and fuel injection pressure on performance and emission behaviour of homogeneous charge compression ignition engine (HCCI) fuelled with diesel fuel. In this investigation, HCCI engine operates with different inlet air temperature and fuel injection pressure, and analysis the effect of these variables on HCCI engine performance and emissions. The inlet air temperatures are varied between 40 °C and 70 °C and the injection pressure in the port fuel injector is varied from 3 bar to 5 bar respectively. From the results, the optimum inlet air temperature and fuel injection pressure for efficient HCCI engine operation are identified. The result shows that, brake thermal efficiency of HCCI is nearer to the value of conventional diesel engine, and can be obtained if HCCI engine operates with 5 bar injection pressure and 60 °C air temperature and a simultaneous reduction in oxides of nitrogen (NOx) and smoke emissions compared to conventional diesel engine. However, when inlet air is heated for improvement of vaporisation of diesel fuel, the higher inlet air temperature limits the operation range of HCCI engine, due to high knocking intensity, high NOx emissions and misfire of charge. The fuel injection pressure is also limited due to high level of HC and NOx emissions

Impact of

The uses of biodiesel in diesel engines result in reduction of exhaust emissions, though many researchers described that the biodiesel produces higher NOx emissions than diesel, which is detract from the inflation of the market for these fuels. The aim of the present study was to analyze the experimental exploration of the three antioxidants DEA (Di-Ethyl Amine), PHC (Pyridoxine Hydro Chloride) and TBHQ (Tert Butyl Hydro Quinone) on engine emission and performance of a single cylinder diesel engine fueled with methyl ester of mango seed. The experiment is conducted with different antioxidant concentrations of mango seed methyl ester mixtures (100, 250, 500 and 1000 ppm).The results exhibited that PHC is effectual in controlling NOx emissions than TBHQ and DEA

Experimental investigation of a diesel engine with methyl ester of mango seed oil and diesel blends

Petroleum based fuels worldwide have not only resulted in the rapid depletion of conventional energy sources, but have also caused severe air pollution. The search for an alternate fuel has led to many findings due to which a wide variety of alternative fuels are available at our disposal now. The existing studies have revealed the use of vegetable oils for engines as an alternative for diesel fuel. However, there is a limitation in using straight vegetable oils in diesel engines due to their high viscosity and low volatility. In the present work, neat mango seed oil is converted into their respective methyl ester through transesterification process. Experiments are conducted using various blends of methyl ester of mango seed oil with diesel in a single cylinder, four stroke vertical and air cooled Kirloskar diesel engine. The experimental results of this study showed that the MEMSO biodiesel has similar characteristics to those of diesel. The brake thermal efficiency, unburned hydrocarbon and smoke density are observed to be lower in case of MEMSO biodiesel blends than diesel. The CO emission for B25, B50 and B75 is observed to be lower than diesel at full load, whereas for B100 it is higher at all loads. On the other hand, BSFC and NOx of MEMSO biodiesel blends are found to be higher than diesel. It is found that the combustion characteristics of all blends of methyl ester of mango seed oil showed similar trends with those of the baseline diesel. From this study, it is concluded that optimized blend is B25 and could be used as a viable alternative fuel in a single cylinder direct injection diesel engine without any modifications

Analysis the optimum inlet air temperature for controlling homogeneous charge compression ignition (HCCI) engine

Homogeneous charge compression ignition engine is promising replacement for conventional CI diesel engine with lower oxides of nitrogen (NOx) and smoke emissions and improves the thermal efficiency with consume less amount of fuel. In general, HCCI engine operates with lean air/fuel charge for all operating condition, and it makes the HCCI combustion more complex and difficult to control the start of ignition point. The inlet air temperature is the primary parameter for controlling the HCCI combustion. In this study, the HCCI engine was operated at different inlet air temperatures as 90 °C, 100 °C, 110 °C, 120 °C, 130 °C, 140 °C and 150 °C respectively. From this study, it was observed that the level of NOx emission increased with increasing the inlet air temperature and smoke emission was reduced with increasing the inlet charge temperature. The inlet air temperature about 120 °C showed maximum reduction of smoke emission about 15HSU at 60% load. Similarly, CO and HC were reduced with increasing the inlet air temperature. The specific fuel consumption of HCCI mode engine decreased with increasing the inlet air temperature and the power output of the engine increased with increasing the suction air temperature. Keywords: Homogeneous charge compression ignition engines, Inlet air temperature, Diesel fuelled, Emission reduction, Improve engine outpu

A COMPREHENSIVE REVIEW ON COMBUSTION OF COMPRESSION IGNITION ENGINES USING BIODIESEL INTERNATIONAL JOURNAL OF MECHANICAL ENGINEERING AND TECHNOLOGY (IJMET) IJMET © I A E M E

ABSTRACT The world today is confronted with a twin crisis of fossil fuel depletion and environmental degradation. Rapid depletion of petroleum derived fuels has forced the researchers to find out alternative fuels for IC engines. Biodiesel is an alternative fuel for conventional diesel engines and can be used without major modification of the engines. When compared to diesel, biodiesel has a higher cetane number which results in shorter ignition delay and longer combustion duration and hence results in low particulate emissions. The combustion of CI engine is a complex process due to its combustion mechanism. The combustion characteristics of an engine are defined by parameters such as cylinder pressure, maximum rate of pressure rise, heat release, cumulative heat release, ignition delay and combustion duration. Analysis of combustion characteristics is significant because it provides the important information which in turn helps in interpreting the engine performance and exhaust emissions. This paper reviews the combustion analysis of compression ignition engines using biodiesel. It is found that the ignition delay for biodiesel seems to be less when compared to diesel. Moreover, it reveals that the heat release rate is more during the diffusion combustion for biodiesel and its blends than diesel. Similarly a marked difference is seen in the cumulative heat release rate and combustion duration