Effect of Biodiesel-Ethanol Blended Fuel Spray Characteristics on the Reduction of Exhaust Emissions in a Common-Rail Diesel Engine

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
Seung Hyun Yoon ◽  
Su Han Park ◽  
Hyun Kyu Suh ◽  
Chang Sik Lee

An experimental investigation was performed to analyze the effects of biodiesel-ethanol blended fuel spray on the combustion, and exhaust emission characteristics in a single cylinder common-rail diesel engine. In order to analyze the macroscopic and microscopic characteristics of biodiesel blended fuel spray, parameters, such as injection rate, droplet diameter, and spray tip penetration, were measured using an injection rate meter system, spray visualization, and droplet measuring system. Also, measurements of combustion, exhaust emissions, and size distributions of particulate matter were carried out under various engine operating conditions for biodiesel-ethanol blends and the results were compared with those of conventional diesel fuel. In this investigation, the measured results of biodiesel-ethanol blended fuel show that the Sauter mean diameter decreased with the increase of relative velocity between the injected fuel and the ambient gas. Comparing the combustion characteristics of diesel fuel and biodiesel-ethanol blended fuels, both diesel and blended fuel show similar trends of combustion pressure and rate of heat release. However, the combustion of biodiesel-ethanol blends indicated lower combustion characteristics, such as combustion pressures and heat release rates, than those of diesel fuel because of its lower heating value. In the case of exhaust gas recirculation, the indicated specific NOx(ISNOx) and soot concentration results showed lower emissions compared with those of conventional diesel fuel.

Author(s):  
Seung Hyun Yoon ◽  
Su Han Park ◽  
Hyun Kyu Suh ◽  
Chang Sik Lee

An experiment was performed to analyze the effects of biodiesel-ethanol blended fuel spray on the combustion and exhaust emission characteristics of a single-cylinder common-rail diesel engine. To analyze the macroscopic and microscopic characteristics of biodiesel blended fuel spray, measurements of the injection rate, droplet diameter, and spray tip penetration were taken using an injection rate meter, spray visualization and a droplet measuring system. The combustion, exhaust emission characteristics and size distributions of particulate matter were determined for various engine operating conditions using biodiesel-ethanol blends, and the results were compared to those of conventional diesel fuel. In this investigation, the measured results of biodiesel-ethanol blended fuels show that the Sauter mean diameter (SMD) decreased with an increase of relative velocity between the injected fuel and ambient gas. Comparing the combustion characteristics of diesel fuel and biodiesel-ethanol blended fuels, both diesel and blended fuel showed similar trends in combustion pressure and the rate of heat release. However, the combustion of biodiesel-ethanol blends had lower combustion characteristics such as combustion pressures and heat release rates than those of diesel fuel because of their lower heating values. In the case of exhaust gas recirculation (EGR), the indicated specific NOx (ISNOx), and soot concentrations were lower than those of conventional diesel fuel.


Author(s):  
Hyun Kyu Suh ◽  
Hyun Gu Roh ◽  
Chang Sik Lee

The aim of this work is to investigate the effect of the blending ratio and pilot injection on the spray and combustion characteristics of biodiesel fuel and compare these factors with those of diesel fuel in a direct injection common-rail diesel engine. In order to study the factors influencing the spray and combustion characteristics of biodiesel fuel, experiments involving exhaust emissions and engine performance were conducted at various biodiesel blending ratios and injection conditions for engine operating conditions. The macroscopic and microscopic spray characteristics of biodiesel fuel, such as injection rate, split injection effect, spray tip penetration, droplet diameter, and axial velocity distribution, were compared with the results from conventional diesel fuel. For biodiesel blended fuel, it was revealed that a higher injection pressure is needed to achieve the same injection rate at a higher blending ratio. The spray tip penetration of biodiesel fuel was similar to that of diesel. The atomization characteristics of biodiesel show that it has higher Sauter mean diameter and lower spray velocity than conventional diesel fuel due to high viscosity and surface tension. The peak combustion pressures of diesel and blending fuel increased with advanced injection timing and the combustion pressure of biodiesel fuel is higher than that of diesel fuel. As the pilot injection timing is retarded to 15deg of BTDC that is closed by the top dead center, the dissimilarities of diesel and blending fuels combustion pressure are reduced. It was found that the pilot injection enhanced the deteriorated spray and combustion characteristics of biodiesel fuel caused by different physical properties of the fuel.


Author(s):  
Hyun Kyu Suh ◽  
Hyun Gu Rho ◽  
Chang Sik Lee

The aim of this work is to investigate the effect of mixing ratio and pilot injection on spray and combustion characteristics of biodiesel fuel and compared with those of diesel fuel in a direct injection common-rail diesel engine. In order to study the influence factors of biodiesel fuel on the spray and combustion characteristics, the experiments were conducted at various mixing ratios and injection conditions of the biodiesel and engine operating conditions. The macroscopic and microscopic characteristics such as injection rate, split injection effect, spray tip penetration, droplet diameter, and axial velocity distribution of biodiesel fuel were compared with the results of conventional diesel fuel by using spray visualization system composed of Ar-ion laser, ICCD camera and phase Doppler particle analyzer (PDPA) system. The combustion and exhaust emission characteristics of biodiesel fuel were studies using common-rail diesel engine with four cylinders. For the biodiesel blended fuel, it was revealed that higher injection pressure is needed to achieve the same injection rate at the higher mixing ratio. The spray tip penetration of biodiesel fuel was much the same with those of diesel. The atomization characteristics of biodiesel were inferior to conventional diesel fuel due to high viscosity and surface tension. The peak combustion pressures of both fuels were increased with advanced injection timing and the combustion pressure of biodiesel fuel is higher than that of diesel fuel. As the pilot injection timing is advanced to the TDC, the dissimilarities of both fuels combustion pressure are reduced. It can be also founded that the pilot injection can enhance the deteriorated spray and combustion characteristics of biodiesel fuel caused by physical fuel properties.


2011 ◽  
Vol 354-355 ◽  
pp. 462-467
Author(s):  
Cui Ping Zhang ◽  
Xu Mao Zhai ◽  
Yu Juan Li ◽  
Zhi Gang Sun

Methanol and diesel are almost not soluble, which greatly limits the further study and popularization of the methanol-diesel fuel. To study the emission and combustion characteristics, the 4100 turbocharged and intercooled diesel engine was fueled with 0# diesel and M10 with different additives in the experiment. The result shows that, the maximum cylinder pressure and the peak of the heat release rate in the initial stage of combustion for M10 with iso-octanol and isooctyl nitrate as additive are higher than that of diesel, while the soot emission is lower and NOx emission is slightly higher than diesel’. The maximum cylinder pressure and the heat-release peak in the initial stage of combustion for M10 with dimethyl ether as additive are both lower than diesel’, and the NOx and soot emissions are obviously decreased. The power of the two blend fuels is lower than that of diesel but the magnitude is small, meanwhile the HC emission is slightly increased, while the CO emission is little declined.


Author(s):  
Valentin Soloiu ◽  
Yoshinobu Yoshihara ◽  
Kazuie Nishiwaki ◽  
Yasufumi Nakanishi

The authors investigated the formulation, combustion and emissions of polypropylene (PP)–diesel fuel mixtures in a direct injection diesel engine. The fuel has been obtained by an original technology they developed, in which the low or high density polypropylene (LDPP, HDPP), have been mixed in a nitrogen atmosphere at 200 °C, 10–40% by wt. in diesel fuel. The kinematic viscosity of the polypropylene-diesel fuels was investigated between 25–250 °C and the results showed that viscosity of the plastic mixtures is much higher than that of diesel alone, ranging from 10 cSt to 500 cSt, and depending on the plastic structure, content, and temperature. The TGA and DTA analysis has been conducted to investigate the oxidation and combustion properties of pure PP and polymerdiesel fuels. The results showed that at about 125 °C, the LDPP melts, but does not decompose up 240 °C, when the oxidation starts, and has a peak of heat release at 340–350 °C, and the process is completed at 400 °C. The engine’s injection system used, was a piston-barrel type pump, capable of an injection pressure of 200 bars. The injector had 4 × 0.200 mm nozzles with a conical tip needle. The 25% PP-diesel mixture had a successful ignition in a direct injection 110 mm bore, omega combustion chamber engine. The ignition delay for polypropylene-diesel mixtures was longer by about 0.5 ms (at 1200 rpm), compared with diesel. The heat release showed a different development compared with the reference diesel fuel, the premixed phase being inhibited while a slow diffusion combustion phase fully developed. The maximum combustion pressure has been 83 bars for diesel and decreased by 2 bars for the blended fuel, while the bulk gas maximum temperature (calculated) reached about 2500 K for diesel vs 2600 K for polypropylene mixture. The heat flux calculated by the Annand model has shown lower values for diesel fuel with a maximum of about 2.7 MW/m2 compared with 3.0 MW/m2 for PP blended fuel with similar values for convection flux for both fuels at about 1.57 MW/m2 and a higher radiation flux of about 1.44 MW/m2 for PP fuel versus 1.27 MW/m2 for diesel. The heat lost during the cycle shows low values for the premixed combustion stage and increased values for the diffusion stage for both fuels. The exhaust temperatures have been practically identical for both fuels for all loads, with emissions of NOx, and CO reduced by 40% for the alternative fuel, while the CO2 exhibited almost the same values for both fuels. The smoke emissions decreased by 60–90% for the polypropylene blended fuel depending on the load, The engines’ overall efficiency was slightly lower for PP fuel at low loads compared with diesel combustion but at 100% load both reached 36%. The study showed that the new formulation process proposed by the authors is able to produce a new class of fuels from diesel blended with low density polypropylene, and resulted in hybrid fuels with very promising combustion prospects. The engine investigation proved that 25% PP fuels can be injected and burnt in a diesel engine at a residence time of about 5 ms from the start of injection, and the engine’s nominal power could be reached, with lower emissions than reference diesel fuel.


2021 ◽  
Vol 13 (17) ◽  
pp. 9677
Author(s):  
Dong Lin Loo ◽  
Yew Heng Teoh ◽  
Heoy Geok How ◽  
Jun Sheng Teh ◽  
Liviu Catalin Andrei ◽  
...  

Two main aspects of the transportation industry are pollution to the environment and depletion of fossil fuels. In the transportation industry, the pollution to the environment can be reduced with the use of cleaner fuel, such as gas-to-liquid fuel, to reduce the exhaust emissions from engines. However, the depletion of fossil fuels is still significant. Biodiesel is a non-toxic, renewable, and biodegradable fuel that is considered an alternative resource to conventional diesel fuel. Even though biodiesel shows advantages as a renewable source, there are still minor drawbacks while operating in diesel engines. Modern vehicle engines are designed to be powered by conventional diesel fuel or gasoline fuel. In this review, the performance, emissions, combustion, and endurance characteristics of different types of diesel engines with various conditions are assessed with biodiesel and blended fuel as well as the effect of biodiesel on the diesel engines. The results show that biodiesel and blended fuel had fewer emissions of CO, HC, and PM but higher NOx emissions than the diesel-fuelled engine. In the endurance test, biodiesel and blended fuel showed less wear and carbon deposits. A high concentration of wear debris was found inside the lubricating oil while the engine operated with biodiesel and blends. The performance, emissions, and combustion characteristics of biodiesel and its blends showed that it can be used in a diesel engine. However, further research on long-term endurance tests is required to obtain a better understanding of endurance characteristics about engine wear of the diesel engine using biodiesel and its blends.


2018 ◽  
Vol 7 (3.11) ◽  
pp. 113
Author(s):  
Idris Saad ◽  
Wardatul Hayah Ab Rashid ◽  
Nur Hidayah Saidon

Petroleum-based fuel reserves are drastically depleting due to a high demand on sustaining a better lifestyle. This paper presents the utilization of waste cooking oil (WCO) as an alternative fuel for diesel engine. Although WCO and conventional diesel fuel have similar physiochemical properties, the properties of WCO is considered inferior than conventional diesel fuel. It is due to higher viscosity and density of WCO while its calorific value is lower than conventional diesel fuel. In this research, unmodified WCO was blended with petrol fuel grade RON97.  Five blended fuels samples were prepared from five to 25 percent volume base with five percent step increment. The density and calorific value of all fuel blend samples together with unmodified WCO were measured and compared to the conventional diesel and RON97 fuels. Each of the blended fuel and conventional diesel were used to run a single cylinder diesel engine. The performance characteristic of the engine was recorded at different engine speeds ranging between 1500 and 3000 rpm. Results showed that the properties of blended fuel were inferior compared to the conventional diesel fuel; however, by adding 15 percent of RON97 into the unmodified WCO, the results were comparable to the conventional diesel fuel.  


Author(s):  
N. V. Mahalakshmi ◽  
R. Karthikeyan

Pinus product (Turpentine) has been proposed as an alternate to petro fuels since the invention of S.I. engine. In general, due to higher volatility, turpentine has been used only in the S.I. engine. But the present work proves that based on the property of turpentine (Table – 1), it is a very good substitute for diesel fuel. The low cetane number of turpentine oil had prevented the use of 100% turpentine oil in diesel engine. The present work explores the performance, emission and combustion characteristics of turpentine diesel blends and its suitability with C.I. engine. The 20% turpentine 80% diesel blend has an equal combustion and performance characteristics with that of diesel fuel. The experimental results show that some of the toxic gases like CO, UBHC and soot are decreased compared to diesel baseline. In particular around 45% to 50% smoke reduction is obtained with higher turpentine blends. Also it proves that 20% addition of turpentine into conventional diesel fuel improve the performance, combustion, and emission to a considerable limit.


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