Standard Diesel Research Articles

Evaluation of the economics of conversion to compressed natural gas for a municipal bus fleet

AbstractDomestic natural gas production has increased markedly in the United States, and now compressed natural gas (CNG) has the potential to become a cleaner and less expensive energy source than diesel fuel for use in the public transportation sector, especially for city bus fleets. This paper provides an economic analysis of possible CNG conversion for Lafayette, IN CityBus Corporation. It uses benefit–cost analysis to compare the total cost of three potential options for bus replacement: standard diesel, hybrid diesel‐electric, and CNG. A spreadsheet model was used to estimate the total cost of these three fleet options over a 15‐year project horizon. Results suggest that the CNG option has the lowest net present value (NPV) cost, and that cost savings would be larger if the corporation could obtain a grant for the CNG fueling station or if the project life span could expand to 20 years. From the environmental perspective, the CNG option would reduce greenhouse gas and particulate emissions particularly in comparison with the diesel option. Monte Carlo simulation was used to examine the inherent riskiness of the three fleet options. CNG is always lower cost than hybrid diesel‐electric. Depending on assumptions regarding the underlying price distributions, the CNG option has a 51–100% chance of being lower cost than the standard diesel option.

Influence of Emulsified Palm Biodiesel as Pilot Fuel in a Biogas Run Dual Fuel Diesel Engine

This study attempts to explore the influence of emulsified palm biodiesel as a pilot fuel in a biogas run dual fuel engine. The intention is to achieve diesel-equivalent performance from a diesel engine, together with a reduction in engine emissions, with complete replacement of fossil diesel with renewable fuels. The results of this study are compared to those for a neat biodiesel (Jatropha)-biogas dual fuel engine run at identical engine settings. For baseline comparison, the results are also compared with a standard diesel run. The results show that with the presence of biogas, emulsified biodiesel as a pilot fuel can present a better dual fuel efficiency (41%) and a lower energy consumption (38%) than neat biodiesel in a piloted study. Also, the presence of a microexplosion of emulsified biodiesel was found to reduce the pilot fuel consumption with the presence of biogas, especially at lower loads, where the burning rate of biogas usually slows down due to the lean gas-air mixture and cooler charge temperature. In addition, emulsified palm biodiesel successfully brings the peak cylinder pressure (PCP) closer (8°ATDC) to top dead center (TDC). This elevates the magnitude of the PCP, which increases the expansion ratio and hence improves engine efficiency. With the presence of emulsified biodiesel, the supply of biogas is found to get reduced, especially at higher loads, which in turn reduces the hydrocarbon emission. However, other emission characteristics are not as exciting, and hence emulsified biodiesel in biogas dual fuel mode needs to be further explored at various engine-operating characteristics in order to obtain a superior emission performance.

Performance and Emission Characteristics of Low Heat Rejection Diesel Engine Fuelled with Rice Bran Oil Biodiesel

In this study, the performance and exhaust emissions of a biodiesel fuelled low heat rejection (LHR) direct injection Diesel engine have been investigated experimentally and compared with the results of standard diesel engine without any coatings. Piston, cylinder head, exhaust and inlet valve of test engine were coated with 0.5 mm thickness of zirconia through plasma spray method. Biodiesel used in the testing was prepared from rice bran oil through transesterification process.

Experimental investigation of the impact of biodiesel on the combustion and emission characteristics of a heavy duty diesel engine at various altitudes

As a widely recommended alternative fuel for diesel engines, biodiesel has been proven to be useful for the reduction of emissions from diesel engines, especially particle emissions. Equipped with an on-board engine test bench and a portable emission measurement system designed for mobile tests, this work investigated the emission of a Euro III emission standard heavy-duty diesel engine fueled with petroleum diesel and soybean-oil biodiesel at four different altitudes. Combustion data were also collected during the emission test at each altitude, which was helpful for the analysis of the emission results. These results showed that the use of biodiesel at high altitude advanced the start of ignition and reduced the proportion of the premixed combustion stage. The PM (particulate matter), THC (total hydrocarbon) and CO (carbon monoxide) emissions of the engine fueled with biodiesel were reduced at each investigated altitude, but the reduction of PM and THC emissions caused by biodiesel decreased as the altitude increased. The NOX (nitrogen oxides) emission of both fuels showed no obvious variation with altitude, and the use of biodiesel led to a slight reduction in NOX emission.

구동방식이 다른 서보유압형 인젝터의 분사응답성 연구

In this paper, high-pressure injection characteristic of servo hydraulic injector as the key component of diesel CRDi system, which is driven by solenoid and piezo-actuator were examined by experimental analysis. High-pressure injection characteristic of standard diesel fuel injected at high pressure up to 160 MPa was investigated at high-pressure chamber by using a high-speed camera for spray visualization and quantitative analysis. By this study, we found that the piezo-driven injector has better performances in controlling the fuel injection with the high pressure, including fuel quantity, spray penetration length and spray velocity, than that of a solenoid-driven injector. In particular, the needle response time for start of injection in piezo-driven injector was faster of about <TEX>$125{\mu}s$</TEX> than that of solenoid-driven injector. Consequently, it is known that the piezo-driven injector has more degrees of freedom in controlling the fuel injection with the high pressure than solenoid-driven injector.

Operating Characteristics of the A8c22 Engine in an Sm42 Locomotive Fuelled by Mixtures of Rme with Diesel Fuel

Shrnutí Vyzkum vyznamnějši rozšiřeni použiti obnovitelnych zdrojů (bio-paliv) ve spalovacich motorech trva již vice než dvacet let. Jednim z vysledků je i směrnice EU, ktera nařizuje, že v cilovem roce 2020 by mělo byt přidavano až 20 % biopaliv do ropnych paliv. Ve středni Evropě, s ohledem na plodiny rostouci v teto klimaticke zoně, je touto přiměsi zejmena řepkovy olej a jeho metyl estery. Proto se vyzkum tyka těchto paliv. Zkušebnim motorem byl vidlicovy osmivalec s objemem jednoho valce 10,2 dm3, typove značeni 8C22, největši vykon je 530 kW při jmenovitych otačkach 1000 1/min. Tento motor je mimo jine použivan v posunovacich lokomotivach SM42. Po předchozich diagnostickych průzkumech bylo použita čtyři paliva: standardni nafta (B0), to same palivo se 40 % přiměsi (B40) a 50 % RME - metyl ester řepkoveho oleje (B50). Nasledně bylo zkoušeno palivo B50+ se specialnimi aditivy. Vyzkum energetickych parametrů a toxicity vyfukovych plynů byl provaděn na motoru zabudovanem do lokomotivy SM42. Zkoušky byly provaděny podle metodiky 2004/26/WE a UIC 624 Chart. Bylo zjištěno, že narůst podilu RME (metylesteru řepkoveho oleje) až do hodnoty 50 % v naftě, zvyšuje hodnotu hodinove spotřeby až o 10 % při volnoběhu a až o 15 % při plnem zatiženi motoru oproti motorove naftě. Dale bylo zjištěno, že koncentrace CO ve vyfukovych plynech s rostouci koncentraci esteru v palivu při volnoběhu, při středni zatěži se neměni a naopak při plne zatěži motoru koncentrace CO klesaji. Pro malou a středni zatěž byl vypozorovan pokles HC. Při volnoběhu bylo zjištěno sniženi emisi NOx při narůstu koncentrace RME. To je pro posunovaci lokomitivy vyznamne, protože často pracuji při volnoběhu. Pro zkoušena paliva, byla stanoveny odolnost vůči karbonizaci vstřikovačů a některe tribologicke charakteristiky. Paliva obsahujici do 40 % RME vyhovuji kriteriu vzniku karbonizace.

Effects of Incomplete Transesterification Reaction of Palm Oil Biodiesel on Fuel Quality and Engine Performance

This study investigates how an incomplete tranesterification reaction influences the parameters of quality standards of the produced biodiesel engine performance and exhausts. The parameters evaluated include viscosity, cloud point, acid number and heating value. Biodiesels produced from palm oil were examined in terms of engine performance, where the 3-liter engine with a 4 cylinders 4 strokes, was used. The proportion of methyl ester in biodiesel was varied by adding appropriate amounts of triglyceride. Properties of biodiesel with the methyl ester between 75% and 96.8% by mass were tested against the standard diesel. The engine performance and thermal efficiency when using biodiesels of different qualities were determined under the operating engine speed range between 1,800 and 4,000 rpm. It was found that while the cloud point was raised with methyl ester content the viscosity was decreased. In terms of engine performance, greater proportion of methyl ester provides greater fuel conversion efficiency as well as specific fuel consumption rate. Incomplete conversion of triglyceride to methyl ester, which led to lower methyl ester content, significantly affected the engine performance and emissions. In overall, biodiesel with higher methyl ester content provided better engine performance and exhaust quality.

Theoretical Route toward the Estimation of Second Law Potential of an Emulsified Palm Biodiesel Run Diesel Engine

AbstractThe application of biodiesel as an alternative to diesel is well recognized. However, having a lesser calorific value than diesel, it results in a lower power and efficiency. This can suitably be improved by emulsifying biodiesel with water. However, the properties of biodiesel emulsions are not similar to that of diesel. Hence, the energy and availability distribution of a biodiesel emulsion–run engine will not be identical to that of a diesel-run engine at standard diesel settings. To enlighten this ambiguous fact of literature, an energy-exergy analysis has been performed for a water-in-biodiesel emulsion run diesel engine for a set of compression ratios (CRs) and injection timings (ITs) at full engine load. The biodiesel considered for the study is palm oil methyl ester (POME). The parameters analyzed are the energy and exergy potential of fuel input, shaft work, cooling water, exhaust gas, and exergy destruction. Side by side, the effects of the variation of CR and IT on peak pressure, peak h...

An experimental investigation of effect on diesel engine performance and exhaust emissions of addition at dual fuel mode of hydrogen

Internal combustion engines are an indispensable part of our daily life, especially in transportation and agriculture sectors. However, the reduction of petroleum resources and environmental problems are leading to an increasing trend towards alternative energy sources. In this regard, hydrogen usage is expected to be a solution for previously mentioned problems as one of the renewable energy resources. In this concept, effects of hydrogen as an additional fuel used in a compression ignition engine performance and exhaust emissions parameters different engine speeds were investigated at full load. For this purpose, a compression ignition engine (CI) with 17/1 compression ratio, four cylinders, four stroke, turbocharger and 3.908liters engine volume was used. While diesel fuel was injected directly to combustion chamber, hydrogen was added to inlet manifold at rates of 2.5%, 5% and 7.5% as volume.As a result, an increase in engine torque, power, thermal efficiency, nitrogen oxides (NOx) and exhaust gasses temperatures were acquired at every hydrogen addition ratio while a decrease in hydrocarbons (HC), carbon monoxide (CO) and oxygen (O2) emissions were attained. While engine torque exhibited an increase at a rate of 8.3% comparing with standard diesel operation at 1250min−1 and 7.5% hydrogen addition ratio, engine power increased 17% at 2250min−1 engine speed and 7.5% hydrogen addition ratio. Brake thermal efficiency of 2.5% was obtained as 40.4% comparing with 33% value of SDI at 1750min−1. The lowest CO, CO2, HC and NOx emission values were obtained at 2250min−1 engine speed and 2.5% hydrogen addition ratio as 0.013; 2500min−1 engine speed and 7.5% hydrogen addition ratio as 7.4%; 1250min−1 engine speed and 2.5% hydrogen addition ratio as 10ppm and 1000min−1 engine speed and 7.5% hydrogen addition ratio as 1092ppm respectively comparing with standard diesel operation.

Impact of Fischer–Tropsch and biodiesel fuels on trade-offs between pollutant emissions and combustion noise in diesel engines

Over recent decades, direct injection diesel engines have become the propulsion systems most commonly used in automotive vehicles in Europe. Their leading position in the European market is due to improvements in performance, driveability and their capacity for facing the increasingly restrictive standards to which are subject. Nevertheless, their main drawbacks are related to the emission levels, the use of fossil fuels and the engine noise. To mitigate the first two problems, alternative fuels are being used in these engines with encouraging results. The impact of these fuels on engine noise might therefore be analyzed in order to evaluate the feasibility of such a solution. In this work the effect of diverse alternative fuels on emissions, performance and engine noise quality was analyzed. Compared with standard diesel fuel, results show a scarce variation of combustion noise quality whereas soot level decreases, NOx emissions increase and specific consumption deteriorates.

Comparatives Study of Production Biodiesel from Soybean oil and Jatropha Curcas Seeds Oil

This study involves transesterification of soybean and Jatrophaoils with methanol, using sodium hydroxide as the catalyst to producedbiodiesel as an alternative to petroleum diesel. This work investigatesthe effects of temperature and time on the production of biodiesel fromthe feed stocks employed. Also investigated are the effects of particlesize and temperature on the production of oil from the Jatropha seed.The produced biodiesels from soybean and Jatropha oil were character-ised to determine their suitability as a replacement for the petrol diesel.Results obtained shows that both temperature and time influence theproduction of biodiesel from the soybean and Jatropha oil. Analyses ofthe produced biodiesels also indicates that the properties of the biodie-sels produced shows that the density, refractive index, moisture content,viscosity, flash point, cetane number, pour point and sulphur content ofthe biodiesel produced from soybean oil are 0.882g/cm3, 1.486, 0.018%,6.24cP, 148°C, 51.3, –8.2 and 0.004% respectively. While the correspond-ing values of these properties for the biodiesel produced from Jatrophaoil are 0.861g/cm3, 1.532, 0.013%, 2.8cP, 89°C, 49.5, –7.9 and 0.001%. Itcan be inferred from the results on the properties of biodiesel that theproperties of the produced biodiesels from soybean and Jatropha oilsfit well within the set limits for the standard biodiesel and fossil diesel,the biodiesel can therefore be used as a replacement for the petrol diesel.Results of various analyses conducted on the biodiesels produced fromsoybean and Jatropha oil shows that biodiesel of good qualities can alsobe produced from the Jatropha oil and can be used as a substitute forproduction of biodiesel from soybean which is edible oil.

Studies on a diesel engine fuelled with used transformer oil at different fuel injection nozzle opening pressures

After prolonged use of transformer oils they become waste and utilised in minor applications. Used transformer oil (UTO) possess physical properties similar to diesel fuel. Earlier investigation reveals that the UTO fuelled in a single cylinder, four stoke, direct injection diesel engine developing 4.4 kW at a rated speed of 1500 rpm at 200 bar standard nozzle opening pressure, gave lower brake thermal efficiency and nitric oxide emission and higher smoke compared to diesel fuel operation. In this investigation, the fuel injector in the same engine was subjected to five different injection nozzle opening pressures (200, 210, 220, 230, 240 and 250). The effect on the performance and emissions of a compression ignition engine were evaluated, compared with standard diesel fuel operation and presented in this paper. Results indicated that UTO at 230 bar fuel nozzle opening pressure gave a better performance with lower emissions than UTO at 200 bar.

Full-scale autothermal reforming for transport applications: The effect of diesel fuel quality

This study evaluates the feasibility of H2 production through a fuel flexible reformer, at realistic operating conditions for electricity supply by FC-APUs in the transport sector. The fuel flexibility is evaluated by comparison of autothermal reforming performance with biodiesel (RME), Fischer–Tropsch, low-sulfur diesel (MK1) and European standard diesel (DIN 590). ATR experiments with two monolithic catalysts, Rh1.0Pt1.0Ce10La10/Al2O3 (CAT 1) and Rh1.0Pt1.0Mg4.0Y5.0/CeO2–ZrO2 (CAT 2), sequentially placed in the axial direction of the reformer length were used for full-scale tests. The O2/C ratio was varied from 0.3 to 0.5 and the H2O/C ratio varied from 2 to 3.5, reaching temperatures in the interval of 700–800°C. The hydrogen production and fuel conversion showed an upward trend from RME<DIN 590<MK1<FT with maximum 42vol.% H2 and 99% fuel conversion for FT diesel.

Effect of Combustion Chamber Design on a DI Diesel Engine Fuelled with Jatropha Methyl Esters Blends with Diesel

In this paper a single cylinder constant speed air-cooled four-stroke direct injection diesel engine of 4.4kW is selected for the experimental investigations to evaluate the performance and emission characteristics fuelled with Jatropha oil (JTME), and its blends (20%, 40%, 60%, 80% and 100%). The performance parameters are analyzed include Brake thermal efficiency whereas exhaust emissions include oxides of nitrogen, HC, Smoke and CO. The results of the experiment in each case were compared with baseline data of diesel fuel. It concluded that lower blend of biodiesel 20% JTME act as best alternative fuel among all tested fuel at full load condition.The experimental investigations on the effect of 20% Jatropha methyl esters (JTME) with diesel on performance, combustion and emission characteristics of diesel engine with different combustion chamber geometries (Spherical, toroidal and Re-entrant).Brake thermal efficiency for toroidal combustion chamber was found higher than that of other two combustion chambers. Smoke density, carbon monoxide and hydrocarbons was observed slightly lower for toroidal combustion chamber compared to the other two but those are lower when compared with standard diesel (SCC). However, nitrogen oxides were slightly lower for toroidal combustion chamber compared to the other two but it is higher when compared with standard diesel (SCC).

Effects of tobacco seed oil methyl ester onperformance and exhaust emissions of dieselengine

Tobacco seed oil (TSO) was considered as a potential alternative fuel for compression ignition engines as the tobacco plant has high ecological tolerance and its farming can be realised on five different climatic regions in Turkey. In this study, the effects of TSO methyl ester (TSOME) on the performance and exhaust emissions of a single cylinder water cooled four-stroke diesel engine were experimentally investigated at full load conditions. The TSOME is mixed with diesel fuel in the mass rates of 10, 20, 50 and 100% (B10, B20, B50 and B100), and all the results tested with TSOME blends were compared with those of the standard diesel fuel. Comparing TSOME with standard diesel fuel, both the brake torque and the power of the engine were found higher 2·5% at B50. Hydrocarbon, CO and smoke emissions are measured lower, whereas the NOx emissions are found high.

Some advantages and challenges of running a Euro IV, V6 diesel engine on a gasoline fuel

Previous work has demonstrated that single-cylinder CI engines, with relatively modest changes to operating conditions over a wide operating range, can be run with both very low NOx and low smoke as well as at high efficiency on fuels with high resistance to autoignition such as gasoline. The purpose of this work was to run a multi-cylinder engine without any major changes to the engine system on a gasoline fuel at constant fuel demand to get better understanding of the possible practical advantages and challenges. A 2.7dm3 Euro IV V6 diesel engine was run on a European standard diesel fuel of 54 CN (Cetane Number) according to the engine map at 1000rpm and 1500rpm at different loads. At the same speeds and loads, it was also run on a 84 RON gasoline but with different injection strategies and operating parameters, such as EGR levels. With gasoline, NOx levels comparable to the diesel map point could be obtained but at lower EGR rates, at lower injection pressures and lower brake specific fuel consumption and with extremely low smoke; however the CO and HC emissions were higher. The engine could not be run at high speeds or at loads greater than 12bar IMEP on gasoline because, without introducing modifications, the fuel overheated and gave rise to vapour-lock problems. Also at high loads, in order to limit NOx emissions, high EGR rates were required but the CO levels were excessive, because the particular turbocharger could not deliver adequate intake pressure at such conditions and hence the intake oxygen levels were too low. Thus further modifications to the fuel system and an alternative turbocharger would be needed to extend the operating range on gasoline. There appears to be potential for simplifying future CI engines e.g. by using lower injection pressures and replacing lean NOx after-treatment by CO and HC control by using gasoline-like fuels.

A Study on Late Intake Valve Closing Miller Cycled Diesel Engine

NO x emissions released from diesel engines have much detrimental effects on the environment. Hence, these emissions must be decreased to the limited values described by regulations. One of the effective methods is to adopt Miller cycle to diesel engine in order to improve the performance and to reduce NO x emissions of a diesel engine. In this study, late inlet valve closing Miller cycle is applied to diesel engine by lowering compression ratio with respect to expansion ratio by closing intake valve 10 and 20 crank angles later than that of standard diesel engine by using zero-dimensional single zone model which was verified with experimental data. The obtained results have been compared with standard diesel engine in terms of performance and NO emissions. The results showed that Miller cycled diesel engine is found more efficient and environmentally friendly with less power output than standard diesel engine.

The Esterification of Jatropha Oil Using Different Short Chain Alcohols to Produce Esters to be Used as Biodiesel Fuel

Esters of jatropha oil with short chain alcohols were prepared and evaluated as biodiesel fuel. The alcohols used include methyl, ethyl, propyl, and butyl alcohols. The volumetric ratio of alcohol to oil was 2:1 and the esterification was carried out at the boiling point of the used alcohol. Sulfuric acid was used as a catalyst at a concentration in the reaction mixture equivalent to 0.17 molar H+. The properties of the esters relevant to its use as a fuel, such as the calorific value, flash point, and viscosity, were compared to those of standard diesel fuel. The results have shown that the calorific value of the prepared esters were very close to that of standard diesel fuel. The flash points were higher than that of diesel fuel and it increases as the chain length of the alcohol increases. Also, the pour points were lower than standard diesel fuel.

Consequences of using biodiesel on the injection and air–fuel mixing processes in diesel engines

A study of the injection process and spray behaviour was made for three different fuels. In particular, blends of rapeseed methyl ester and standard diesel fuel with 5% and 30% biodiesel were used for the current study, as well as pure rapeseed methyl ester. Hydraulic characterization of an eight-hole nozzle was carried out using these three fuels, in order to explore and analyse the influence of the fuel properties on the mass flow rate and the momentum flux at the nozzle exit. Additionally, spray visualization tests were performed in order to obtain information about the spray cone angle, which allows characterization of the air–fuel mixing process. Finally, a theoretical derivation was used to obtain further details of the microscopic characteristics of the spray and to compare the air–fuel mixing efficiencies for the different biodiesel blends.

Combined effects of thermal barrier coating and blending with diesel fuel on usability of vegetable oils in diesel engines

The possibility of using pure vegetable oils in a thermally insulated diesel engine has been experimentally investigated. Initially, the standard diesel fuel was tested in the engine, as base experiment for comparison. Then the engine was thermally insulated by coating some parts of it, such as piston, exhaust and intake valves surfaces with zirconium oxide (ZrO2). The main purpose of engine coating was to reduce heat rejection from the walls of combustion chamber and to increase thermal efficiency and thus to increase performance of the engine that using vegetable oil blends. Another aim of the study was to improve the usability of pure vegetable oils in diesel engines without performing any fuel treatments such as pyrolysis, emulsification and transesterification. Pure inedible cottonseed oil and sunflower oil were blended with diesel fuel. Blends and diesel fuel were then tested in the coated diesel engine. Experimental results proved that the main purpose of this study was achieved as the engine performance parameters such as power and torque were increased with simultaneous decrease in fuel consumption (bsfc). Furthermore, exhaust emission parameters such as CO, HC, and Smoke opacity were decreased. Also, sunflower oil blends presented better performance and emission parameters than cottonseed oil blends.