Performance and emissions analysis of a diesel engine directly fuelled with waste cooking oil biodiesel

This research focuses on a comparative study of the physical and chemical properties of waste cooking oil (WCO) biodiesel with China stage IV diesel fuel. The estimate method of excess air ratio and the heating value ratio of an engine's cylinder mixture are proposed based on the differences of properties of two fuels. The bench tests of engine performance are carried out with an engine fuelled with two fuels separately. The estimated excess air ratio and the heating value ratio of an engine's cylinder mixture through the method are approximate to the experiment results. This comparison demonstrates that the estimate method can be applied to the performance analysis of an engine. Compared with China stage IV diesel, when a diesel engine is fuelled with WCO biodiesel, the torque and power decline from 1.9% to 13.8%; the brake-speci?c fuel consumption rises from 3.7% to 15.6%; CO, HC and PM emissions decrease significantly and NO_X emissions increase slightly.     

Experimental study on particulate and NOx emissions of a diesel engine fueled with ultra low sulfur diesel, RME-diesel blends and PME-diesel blends

Ultra low sulfur diesel and two different kinds of biodiesel fuels blended with baseline diesel fuel in 5% and 20% v/v were tested in a Cummins 4BTA direct injection diesel engine, with a turbocharger and an intercooler. Experiments were conducted under five engine loads at two steady speeds (1500 rpm and 2500 rpm). The study aims at investigating the engine performance, NO_x emission, smoke opacity, PM composition, PM size distribution and comparing the impacts of low sulfur content of biodiesel with ULSD on the particulate emission. The results indicate that, compared to base diesel fuel, the increase of biodiesel in blends could cause certain increase in both brake specific fuel consumption and brake thermal efficiency. Compared with baseline diesel fuel, the biodiesel blends bring about more NO_x emissions. With the proportion of biodiesel increase in blends, the smoke opacity decreases, while total particle number concentration increases. Meanwhile the ULSD gives lower NO_x emissions, smoke opacity and total number concentration than those of baseline diesel fuel. In addition, the percentages of SOF and sulfate in particulates increase with biodiesel in blends, while the dry soot friction decreases obviously. Compared with baseline diesel fuel, the biodiesel blends increase the total nucleation number concentration, while ULSD reduces the total nucleation number concentration effectively, although they all have lower sulfur content. It means that, for ULSD, the lower sulfur content is the dominant factor for suppressing nucleation particles formation, while for biodiesel blends, lower volatile, lower aromatic content and higher oxygen content of biodiesel are key factors for improving the nucleation particles formation. The results demonstrate that the higher NO_x emission and total nucleation number concentration are considered as the big obstacles of the application of biodiesel in diesel engine.     

Emissions characteristics of a diesel engine operating on biodiesel and biodiesel blended with ethanol and methanol

Euro V diesel fuel, pure biodiesel and biodiesel blended with 5%, 10% and 15% of ethanol or methanol were tested on a 4-cylinder naturally-aspirated direct-injection diesel engine. Experiments were conducted under five engine loads at a steady speed of 1800 r/min. The study aims to investigate the effects of the blended fuels on reducing NO_x and particulate. On the whole, compared with Euro V diesel fuel, the blended fuels could lead to reduction of both NO_x and PM of a diesel engine, with the biodiesel-methanol blends being more effective than the biodiesel-ethanol blends. The effectiveness of NO_x and particulate reductions is more effective with increase of alcohol in the blends. With high percentage of alcohol in the blends, the HC, CO emissions could increase and the brake thermal efficiency might be slightly reduced but the use of 5% blends could reduce the HC and CO emissions as well. With the diesel oxidation catalyst (DOC), the HC, CO and particulate emissions can be further reduced.     

Experimental investigation of performance,combustion and emission characteristics of CI engine fuelled with chicha oil biodiesel

As the decreasing availability of the fossil fuel is rising day by day, the search of alternate fuel that can be used as a substitute to the conventional fuels is rising rapidly. A new type of biofuel, chicha oil biodiesel, is introduced in this work for the purpose of fuelling diesel engine. Chicha oil was transesterified with methanol using potassium hydroxide as catalyst to obtain chicha oil methyl ester (COME). The calorific value of this biodiesel is lower, when compared to that of diesel. The COME and their blends of 20%, 40%, 60% and 80% with diesel were tested in a single cylinder, four stroke, direct injection diesel engine and the performance, combustion and emission results were compared with diesel. The test result indicates that there is a slight increase in brake thermal efficiency and decrease in brake-specific fuel consumption for all blended fuels when compared to that of diesel fuel. The use of biodiesel resulted in lower emissions of CO and HC and increased emissions of CO₂ and NO_x. The experimental results proved that the use of biodiesel (produced from chicha oil) in compression ignition engine is a viable alternative to diesel.     

Emission reduction potential of using gas-to-liquid and dimethyl ether fuels on a turbocharged diesel engine

A study of engine performance characteristics and both of regulated (CO, HC, NO_x, and smoke) and unregulated (ultrafine particle number, mass concentrations and size distribution) emissions for a turbocharged diesel engine fueled with conventional diesel, gas-to-liquid (GTL) and dimethyl ether (DME) fuels respectively at different engine loads and speeds have been carried out. The results indicated that fuel components significantly affected the engine performance and regulated/unregulated emissions. GTL exhibited almost the same power and torque output as diesel, while improved fuel economy. GTL significantly reduced regulated emissions with average reductions of 21.2% in CO, 15.7% in HC, 15.6% in NO_x and 22.1% in smoke in comparison to diesel, as well as average reductions in unregulated emissions of total ultrafine particle number (N_tot) and mass (M_tot) emissions by 85.3% and 43.9%. DME can significantly increase torque and power, compared with the original diesel engine, as well as significantly reduced regulated emissions of 40.1% in HC, 48.2% in NO_x and smoke free throughout all the engine conditions. However, N_tot for DME is close to that for diesel. The reason is that the accumulation mode particle number emissions for DME are very low due to the characteristics of oxygen content and no C-C bond, which promotes the processes of nucleation and condensation of the semi-volatile compounds in the exhaust gas, as a result, a lot of nucleation mode particles produce.     

Study on the outcome of a cetane improver on the emission characteristics of a diesel engine

ABSTRACT

Dimethyl carbonate (DMC), a cetane improver, is used as a fuel additive to investigate the exhaust emission in diesel engine. Neem oil biodiesel (B100), neem oil biodiesel + dimethyl carbonate (B100+DMC) and diesel were used as test fuels. DMC is added 0.5% by volume to biodiesel. This research work was executed in a four-stroke, single-cylinder diesel engine. Owing to the percentage of DMC in biodiesel, carbon monoxide (CO) and hydrocarbon (HC) emissions were dropped corresponding to diesel. A considerable amount of nitrogen oxide (NO_x) is decreased when diesel is used, and by the addition of B100+DMC, NO_x were slightly reduced compared to B100.     

Experimental analysis of Deccan hemp oil as a new energy feedstock for compression ignition engine

This study investigates the biodiesel from Deccan hemp oil and its blends for the purpose of fuelling diesel engine. The performance and emission characteristics of Deccan hemp biodiesel are estimated and compared with diesel fuel. The experimental investigations are carried out with different blends of Deccan hemp biodiesel. Results show that brake thermal efficiency is improved significantly by 4.15% with 50 BDH when compared with diesel fuel. The Deccan hemp biodiesel reduces NO_x, HC and CO emission along with a marginal increase in CO₂ and smoke emissions with an increase in the biodiesel proportion in the diesel fuel. The improvement in heat release rates shows an increase in the combustion rate with different percentage blends of Deccan hemp biodiesel. From the engine test results, it has been established that 30–50 BDH of Deccan hemp biodiesel can be substituted for diesel.     

Effect of exhaust gas recirculation on a nanoparticle-doped biodiesel- and diesel-blends-fuelled diesel engine

ABSTRACT

This work investigates the effect of adding Cerium oxide nanoparticles at different proportions (30, 60 and 90?ppm) to Calophyllum inophyllum methyl ester and diesel blends (20% CI methyl ester and 80% diesel) in a four-stroke single-cylinder diesel engine. Addition of nanoparticles is a strategy to reduce emission and to improve the performance of the biodiesel. Modified fuels are introduced into the engine by admitting exhaust gas recirculation (EGR) at a rate of 10% and 20% so as to reduce nitrogen oxide (NO_X) emissions from biodiesel and diesel blends. Results revealed a significant reduction in emissions (CO, NO_X, HC and Smoke) at a 10% EGR rate. However, brake thermal efficiency is reduced with an increase in brake-specific fuel consumption at higher EGR rates. Hence, it is observed that 10% EGR rate is an effective method to control the emission of biodiesel and diesel blends without compromising much on engine efficiency.     

Experimental investigations on the influence of properties of Calophyllum inophyllum biodiesel on performance,combustion, and emission characteristics of a DI diesel engine

The current state of future energy and environmental crises has revitalised the need to find alternative sources of energy due to escalating oil prices and depleting oil reserves. To meet increasing energy requirements, there has been a growing interest in alternative fuels like biodiesel that can become a suitable diesel fuel substitute for compression ignition engine. Biodiesel offers a very promising alternative to diesel fuel, since they are renewable and have similar properties. Calophyllum inophyllum seed oil collected from different restaurants in the Nagapattinam region of South India was converted into methyl esters (biodiesel) by transesterification. Biodiesel produced from C. inophyllum oil was blended with diesel by different volume proportions (25%, 50%, and 75%). Biodiesel and its blends were tested on a direct injection (DI) diesel engine at a constant speed by varying loads from 0% to 100% in steps of 20% to analyse its performance, emission, and combustion characteristics. The results obtained were compared with that of diesel fuel. B25 (27.5%) showed better performance than diesel fuel (26.28%) at full load and B50 showed performances similar to diesel fuel. Smoke density of B25 was slightly (2.6%) higher than that of diesel at full load conditions. At full load, measured carbon monoxide emissions for B25 and B50 were 4% lower than that of diesel. Hydrocarbon emissions for B25 and B100 were 5.37% and 25.8% higher than that of diesel, respectively. Nitrogen oxides (NO_x) emission was lower for all biodiesel blends. NO_x emissions of B100 and B75 were lower than that of diesel by 22.16% and 13.29% at full load, respectively. Combustion profile was smoother, and no knocking problem was observed while operating with biodiesel blends. B75 produced peak cylinder pressure.     

Effect of the addition of 1-pentanol on engine performance and emission characteristics of diesel and biodiesel fuelled single cylinder diesel engine

ABSTRACT

Bioalcohols have recently become one of the promising alternate fuels. Lower alcohols exhibit some problems like phase separation, stability issues, storage problems, corrosion etc. Hence, the addition of higher alcohols is regarded least-problematic and the concept of using higher alcohols as fuel blends is relatively new. In this article, the effects of the addition of higher alcohol (1-pentanol) on engine performance and emission characteristics are discussed. Two reference fuels (diesel and biodiesel derived from waste cooking oil) and two test fuels (blends of 20% of 1-pentanol and 80% of either diesel or biodiesel) are tested in a single cylinder compression ignition diesel engine for six load conditions (0, 4, 8, 12, 16, and 20?kg) at a constant speed of 1200?rpm. The engine performance and emission characteristics are determined and discussed.     

Performance analysis of low heat rejection diesel engine,using Mahua oil bio fuel

In the present investigation, the effect of thermal barrier coated piston on the performance and emission characteristics of mahua-biodiesel-fuelled diesel engine was studied and compared with those of neat diesel fuel. The piston, cylinder walls and the valves of the engine were coated with 0.25?mm thickness of Al₂O₃ material without affecting the compression ratio of the engine. Experiments were conducted using diesel and biodiesel blend (B20) in the engine with and without coating. The results revealed that specific fuel consumption was decreased by 8.5% and the brake thermal efficiency was increased by 6.2% for biodiesel blend with coated engine compared with the base engine with neat diesel fuel. The exhaust emissions CO, NO_x and HC emissions were also decreased for biodiesel blend with coated engine compared with base engine.     

Enhancement in the performance of a diesel engine fuelled with Pongamia methyl ester and n-butanol as oxygenated additive

The present paper investigates the performance and emission characteristics of a single-cylinder, four-stroke diesel engine fuelled with Pongamia methyl ester (PME) and n-butanol, at different loading conditions. Two blends of n-butanol–PME (10% and 20% n-butanol with PME on a volumetric basis) were prepared. The experimental results showed a significant improvement in the brake thermal efficiency of the engine with the blends and were found to increase with increasing percentage of n-butanol in the blends. The blended fuels also show lower emission such as carbon monoxide (CO), oxides of nitrogen (NO_x) and smoke opacity. However, unburned hydrocarbon (HC) emission was found to be slightly increased. Thus, it is concluded that the biodiesel with 20% n-butanol blend showed better results with respect to efficiency and emissions point of view compared with biodiesel.     

Effect of exhaust gas recirculation on performance and emission characteristics of a diesel engine fuelled with tamarind biodiesel

The present research work focuses on the influence of exhaust gas recirculation (EGR) on the characteristics of the diesel engine operated with 20% tamarind seed methyl ester (TSME 20) as the renewable fuel. The use of TSME 20 as biodiesel results in closer performance characteristics with diesel fuel. However, TSME 20 biodiesel blend generated higher oxides of nitrogen (NO_X) emissions at all operating conditions. Firstly, tests are performed using diesel and TSME 20 biodiesel blend at constant speed under different loads. Thereafter, experiments are conducted on TSME 20 with EGR rates at different concentrations. The test results revealed that with TSME 20 with 20% EGR rate, NO_X emissions are reduced by 45.67% and 52.69% when compared to diesel and TSME 20. However, there is a slight reduction in brake thermal efficiency. Hence, the use of 20% EGR rate to TSME 20 is an optimum approach for better control of NO_X emissions.

Abbreviations BDC: bottom dead centre; BMEP: brake mean effective pressure; BSFC: brake-specific fuel consumption; BTE: brake thermal efficiency; CO: carbon monoxide; CO₂: carbon dioxide; EGR: exhaust gas recirculation; FSN: filter smoke number; HC: hydrocarbon; kWh: kilo Watt hour; NO_X: oxides of nitrogen; ppm: parts per million; SO: smoke opacity; TDC: top dead centre; TSME: tamarind seed methyl ester; TSME 20: 20% tamarind seed methyl ester; TSME 20–20%: tamarind seed methyl ester with 80% diesel; TSME 10% EGR: TSME 20 with 10% exhaust gas recirculation; TSME 20% EGR: TSME 20 with 20% exhaust gas recirculation; TSME 30% EGR: TSME 20 with 30% exhaust gas recirculation     

Performance and emission characteristics of cashew nut shell oil on the CI engine

This article is an effort to address the need for a non-cooking oil-based biodiesel. Here, the experimental work is done on a single cylinder, direct injection CI engine using cashew nut shell oil biodiesel blends under constant speed. The cashew nut shell liquid (CNSL) biodiesel is blended with the diesel fuel and used as biodiesel blend. Blends used for testing are B20, B40 and B60. The effect of the fuels on engine power, brake thermal efficiency (BTE) and exhaust gas temperature was determined by performance tests. The influences of blends on CO, CO₂, HC and NO_x emissions were investigated by emission tests. The BTE values of biodiesel are closer to diesel. Compared to diesel, all the biodiesel blends gave lesser unburnt hydrocarbon (HC), carbon monoxide (CO) and smoke emissions. Slightly higher NO_x emissions were found in CNSL biodiesel blends, which is typical of the other biodiesels.     

A comparative study of performance and combustion characteristics of a CI diesel engine fuelled with B20 biodiesel blends

This paper aims to study the diesel engine performance and combustion characteristics fuelled with Banalities aegyptiaca oil methyl ester, palm oil methyl ester, sesame methyl ester oil, rapeseed methyl ester oil, soybean oil methyl ester and diesel fuel. In this present work, only 20% of each biodiesel blends was tested in diesel engine; stated that the possible use of biodiesel of up to 20% in a diesel engine without modification in literature. A single-cylinder, auxiliary water-cooled and computer-based variable compression ratio diesel engine was used to evaluate their performance at constant speed and at measured load conditions. The performance and combustion tests are conducted using each of the above test fuels, at a constant speed of 5000?rpm. Thus, the varying physical and chemical properties of test fuels against pure diesel are optimised for better engine performance.

Abbreviations: BP: brake power; BSFC: brake-specific fuel consumption; BTE: brake thermal efficiency; CO: carbon monoxide; CP: cylinder pressure; DP: diesel pressure; EGT: exhaust gas temperature; HC: hydrocarbon; HRR: heat release rate; NO _x : nitric oxides; PM: particulate matter; TDC: top dead centre; VCR: variable compression ratio     

Investigation on the gaseous and particulate emissions of a compression ignition engine fueled with diesel-dimethyl carbonate blends

The effect of dimethyl carbonate (DMC) on the gaseous and particulate emissions of a diesel engine was investigated using Euro V diesel fuel blended with different proportions of DMC. Combustion analysis shows that, with the blended fuel, the ignition delay and the heat release rate in the premixed combustion phase increase, while the total combustion duration and the fuel consumed in the diffusion combustion phase decrease. Compared with diesel fuel, with an increase of DMC in the blended fuel, the brake thermal efficiency is slightly improved but the brake specific fuel consumption increases. On the emission side, CO increases significantly at low engine load but decreases at high engine load while HC decreases slightly. NO_x reduces slightly but the reduction is not statistically significant, while NO₂ increases slightly. Particulate mass and number concentrations decrease upon using the blended fuel while the geometric mean diameter of the particles shifts towards smaller size. Overall speaking, diesel-DMC blends lead to significant improvement in particulate emissions while the impact on CO, HC and NO_x emissions is small.     

Emission reduction from diesel engine using fumigation methanol and diesel oxidation catalyst

This study is aimed to investigate the combined application of fumigation methanol and a diesel oxidation catalyst for reducing emissions of an in-use diesel engine. Experiments were performed on a 4-cylinder naturally-aspirated direct-injection diesel engine operating at a constant speed of 1800 rev/min for five engine loads.The experimental results show that at low engine loads, the brake thermal efficiency decreases with increase in fumigation methanol; but at high loads, it slightly increases with increase in fumigation methanol. The fumigation method results in a significant increase in hydrocarbon (HC), carbon monoxide (CO), and nitrogen dioxide (NO₂) emissions, but decrease in nitrogen oxides (NO_x), smoke opacity and the particulate mass concentration. For the submicron particles, the total number of particles decreases. In all cases, there is little change in geometrical mean diameter of the particles. After catalytic conversion, the HC, CO, NO₂, particulate mass and particulate number concentrations were significantly reduced at medium to high engine loads; while the geometrical mean diameter of the particles becomes larger. Thus, the combined use of fumigation methanol and diesel oxidation catalyst leads to a reduction of HC, CO, NO_x, particulate mass and particulate number concentrations at medium to high engine loads.     

Experimental investigation of engine emissions with marine gas oil-oxygenate blends

This paper investigates the diesel engine performance and exhaust emissions with marine gas oil-alternative fuel additive. Marine gas oil (MGO) was selected as base fuel for the engine experiments. An oxygenate, diethylene glycol dimethyl ether (DGM), and a biodiesel (BD) jatropha oil methyl ester (JOME) with a volume of 10% were blended with the MGO fuel. JOME was derived from inedible jatropha oil. Lower emissions with diesel-BD blends (soybean methyl ester, rapeseed methyl ester etc.) have been established so far, but the effect of MGO-BD (JOME) blends on engine performance and emissions has been a growing interest as JOME (BD) is derived from inedible oil and MGO is frequently used in maritime transports. No phase separation between MGO-DGM and MGO-JOME blends was found. The neat MGO, MGO-DGM and MGO-JOME blends are termed as MGO, Ox10 and B10 respectively. The experiments were conducted with a six-cylinder, four-stroke, turbocharged, direct-injection Scania DC 1102 (DI) diesel engine. The experimental results showed significant reductions in fine particle number and mass emissions, PM and smoke emissions with Ox10 and B10 fuels compared to the MGO fuel. Other emissions including total unburned hydrocarbon (THC), carbon monoxide (CO) and engine noise were also reduced with the Ox10 and B10 fuels, while maintaining similar brake specific fuel consumption (BSFC) and thermal efficiency with MGO fuel. Oxides of nitrogen (NOx) emissions, on the other hand, were slightly higher with the Ox10 and B10 fuels at high engine load conditions.     

Experimental investigation on regulated and unregulated emissions of a diesel/methanol compound combustion engine with and without diesel oxidation catalyst

The use of methanol in combination with diesel fuel is an effective measure to reduce particulate matter (PM) and nitrogen oxides (NOx) emissions from in-use diesel vehicles. In this study, a diesel/methanol compound combustion (DMCC) scheme was proposed and a 4-cylinder naturally-aspirated direct-injection diesel engine modified to operate on the proposed combustion scheme. The effect of DMCC and diesel oxidation catalyst (DOC) on the regulated emissions of total hydrocarbons (THC), carbon monoxide (CO), NOx and PM was investigated based on the Japanese 13 Mode test cycle. Certain unregulated emissions, including methane, ethyne, ethene, 1,3-butadiene, BTX (benzene, toluene, xylene), unburned methanol and formaldehyde were also evaluated based on the same test cycle. In addition, the soluble organic fraction (SOF) in the particulate and the particulate number concentration and size distribution were investigated at certain selected modes of operation. The results show that the DMCC scheme can effectively reduce NOx, particulate mass and number concentrations, ethyne, ethene and 1,3-butadiene emissions but significantly increase the emissions of THC, CO, NO₂, BTX, unburned methanol, formaldehyde, and the proportion of SOF in the particles. After the DOC, the emission of THC, CO, NO₂, as well as the unregulated gaseous emissions, can be significantly reduced when the exhaust gas temperature is sufficiently high while the particulate mass concentration is further reduced due to oxidation of the SOF.     

Evaporation rate and engine performance analysis of coated diesel engine using Raphanus sativus biodiesel and its diesel blends

An experimental investigation to measure the evaporation rates, PSZ-coated engine performance and emissions of radish biodiesel (Methyl Ester of radish oil) and its blends in different volumetric proportions with diesel is presented. The thermo-physical properties of all the fuel blends have been measured and presented. Evaporation rates of neat radish biodiesel, neat diesel and their bends have been measured under slow convective environment of air velocity of 0.2?m/s with a constant temperature of 200°C. Evaporation constants have been determined by using the droplet regression rate data. The neat fuels and fuel blends have been utilised in a test engine with different load conditions to evaluate the performance and emission characteristics of the fuels. From the observed evaporation, performance and emissions characteristics, it can be suggested that a blend of B25–B75 could be optimally used in coated diesel engine settings without any modifications on it.