Cycle Diesel Engine Research Articles

Comparison of different procedures for the optimisation of a combined Diesel engine and organic Rankine cycle system based on ship operational profile

At a time of strong challenges for shipping in relation to economic and environmental performance, the potential of waste heat recovery has been identified as among the most important technologies to lower fuel consumption. This paper presents the comparison of four different procedures for the optimisation of a combined Diesel and organic Rankine cycle system with increasing attention to the ship operational profile and to the inclusion of engine control variables in the optimisation procedure. Measured data from two years of operations of a chemical tanker are used to test the application of the different procedures. The results indicate that for the investigated case study the application of an optimisation procedure which takes the operational profile into account can increase the savings of the installation of an organic Rankine cycle from 7.3% to 11.4% of the original yearly fuel consumption. The results of this study further show that (i) simulating the part-load behavior of the ORC is important to ensure its correct operations at low engine load and (ii) allowing the engine control strategy to be part of the optimisation procedure leads to significantly larger fuel savings than the optimisation of the waste recovery system alone.

Common Rail Diesel Fuel Injection Management based on FPGA Technology

This paper describes the development of a computer program using the programing software LabViewTM. This computer program is capable of performing real-time electronic management of a Common Rail Diesel cycle engine. This management is done openly, ie can be varied in real time execution input parameters and thus experience the engine response depending on the variation of these parameters. The computer program is focused on a real-time controller NI CRIO-9004 model available from National Instruments Co, which conditions and processes the input signals from several engine sensors and generates output signals to control the various engine actuators. The management of many engine concepts in close loop is performed with the aim of obtaining very precise control of these elements and adaptability to rapid transients.

Economic and environmental benefits of waste-to-energy technologies for debris recovery in disaster-hit Northeast Japan

Since the 3/11 disaster, Japan has doubled its fossil fuel imports to supplement the nuclear power outage. The consequences of this growing dependence on energy imports threaten economic stability and environmental sustainability. More than 28 million tons of rubble and debris have also been washed up on the coastline of the disaster-hit Northeast Japan, presenting significant logistical and environmental challenges. The Government of Japan announced the construction of biomass power plants to simultaneously increase the renewable energy mix and to dispose of the debris. This study evaluates the economic and environmental benefits (capital and lifetime operation costs, non-renewable energy consumption, greenhouse gases (GHG), particulate matter equivalent and sulphur dioxide equivalent emissions) of advanced waste-to-energy biomass technologies, comparing (i) traditional biomass direct combustion with combined heat and power system, (ii) gasification combined with diesel cycle engine, (iii) Fischer-Tropsch combined with diesel cycle engine, and (iv) biomass fermentation for ethanol fuel production. Results show that the gasification pathway is the most energy efficient and the least expensive modern alternative for energy production, but has worse environmental performance compared to higher-cost biorefineries. On the other hand, the co-production of liquid fuels and electricity results in lower local environmental impacts, but the unit cost of energy produced is more than double that of traditional technologies. Fischer-Tropsch is lower cost and cleaner than ethanol plants, making it the more desirable option of the biorefinery technologies.

Ethanol-fueled low temperature combustion: A pathway to clean and efficient diesel engine cycles

Low temperature combustion (LTC) in diesel engines offers the benefits of ultra-low NOx and smoke emissions but suffers from lowered energy efficiency due to the high reactivity and low volatility of diesel fuel. Ethanol from renewable biomass provides a viable alternate to the petroleum based transportation fuels. The high resistance to auto-ignition (low reactivity) and its high volatility make ethanol a suitable fuel for low temperature combustion (LTC) in compression-ignition engines.In this work, a Premixed Pilot Assisted Combustion (PPAC) strategy comprising of the port fuel injection of ethanol, ignited with a single diesel pilot injection near the top dead centre has been investigated on a single-cylinder high compression ratio diesel engine. The impact of the diesel pilot injection timing, ethanol to diesel quantity ratio and exhaust gas recirculation on the emissions and efficiency are studied at 10 bar IMEP. With the lessons learnt, successful ethanol–diesel PPAC has been demonstrated up to a load of 18bar IMEP with ultra-low NOx and soot emissions across the full load range. The main challenge of PPAC is the reduced combustion efficiency especially at low loads; therefore, the authors have presented a combustion control strategy to allow high efficiency, clean combustion across the load range. This work entails to provide a detailed framework for the ethanol-fueled PPAC to be successfully implemented.

Modeling the Combustion Process of a Powerful Diesel Engine

The authors develop models of the combustion process and a program for calculating the operating cycle of a powerful diesel engine with the set law of mixture formation. They also calculate how the temperature of a fresh charge after a charge air cooler impacts the operating cycle indicators of such an engine. Based on the results of the calculation, herein are constructed charts of in-cylinder pressure and heat release laws that accord with known experimental data.

The effects of steam injection on the performance and emission parameters of a Miller cycle diesel engine

The application of the Miller cycle into the internal combustion engines is proposed to decrease NOx emissions, in the recent years. Another NOx control technique is the steam injection method (SIM). In this study, the application of these methods together into a single cylinder, direct injection diesel engine is experimentally and theoretically performed. Two different Miller cycles, which provide 5 and 10 crank angle (CA) retarding compared to standard condition, are applied with two different camshafts. SIM is applied at three different injection rates which are 10%, 20% and 30% of the fuel mass. The results obtained are compared with standard conditions in terms of the performance and emissions. The simulation results are verified with experimental data with non-notable errors. In the experimental results, NO and CO2 emissions decreased up to 48% and 2.2%; HC and CO emissions increased by 46% and 34% with the penalty by 6.4% and 9.2% for the effective power and efficiency. The optimum condition has been defined as 10 CA retarding and 30% steam injection rate (C62-S30) in terms of the maximum NO reduction. The results demonstrate that the combination can be applied into the diesel engines to minimize NO and CO2 emissions.

Theoretical and experimental investigation of the Miller cycle diesel engine in terms of performance and emission parameters

Pollutant exhaust emissions, particularly NOx, produced by diesel engines must be reduced to limit values defined by the environmental regulations as the emissions have many harmful influences on the environment. Recently, the application of the Miller cycle into the internal combustion engines has been proposed to abate NOx emissions. In the present study, the Miller cycle with late intake valve closing (LIVC) version is applied into a single cylinder, four-stroke, direct injection, naturally aspirated diesel engine. Three different cam shafts have been manufactured to provide 5, 10 and 15 crank angle (CA) retarding compared to original camshaft. The optimum retarding angle has been determined as 5 CA in terms of NOx reduction. The attained results have been compared with conventional diesel engine which has standard CA (0 crank angle retarding) in point of the performance and NO, HC, CO emissions. In order to provide a model validation for engine torque, brake power, brake efficiency, specific fuel consumption (SFC) and NO, the Miller cycle diesel engine is modeled by using two-zone combustion model for 5 CA retarding at full load conditions. The simulation results have been verified with experimental data with non-considerable errors. In the experimental results, NO emissions decreased by 30% with 2.5% power loss and a remarkable change is not seen in the HC, CO emissions. The results show that the method could be easily applied into the diesel engine in order to minimize NO emissions.

Future vehicles will be driven by electricity, but not as you think [Point of View

The debate on what will be the car of the future has been ongoing for many years now and only seems to intensify. Throughout the years, there have been many views, some would say hypes, on what would be the most likely candidate technology enabling sustainable transportation. The early 1990s saw the end of the large-scale fleet trials of methanol-fueled vehicles, followed by the introduction of electric vehicles (EVs) some years later. The new millennium started off with high hopes for the hydrogen fuel cell vehicle (FCV). Homogeneous charge compression ignition (HCCI) engines were going to save the day a few years later, combining the best features of the gasoline and diesel engine cycles. In recent years, the pace seems to have picked up: around 2007, biofuels were in the picture (mainly ethanol); in 2009, EVs again came on stage, this time joined by plug-in hybrids and range extended EVs. Most recently, with increased shale gas development, natural gas vehicles (NGVs) have been on the rise.

ANALYSIS OF CALCULATED CYCLES PARAMETERS IN CASE OF NATURAL GAS SUPPLY AND DIESEL ENGINE

The paper is dedicated to comparative analysis of cycles of engines supplied with natural gas having diesel compression ratio and quality power control with the basic diesel engine cycle. Two types of gas engines were investigated: with internal mixture formation and glow plug air-gas mixture ignition; with external mixture formation and air-gas mixture ignition with the help of pilot diesel fuel injection. Calculation results by external speed characteristics demonstrated that the gas engines were at least as good as the base diesel engines as regards to power and fuel efficiency. At the same time they have lower mechanical and thermal loads and considerably lower СО2 emissions.

Biodiesel produced from crambe oil in Brazil—A study of performance and emissions in a diesel cycle engine generator

Abstract The ceaseless search for renewable sources of energy puts biodiesel as a great alternative to replace oil-based fuels. This work aimed to assess the specific consumption of fuel, thermal efficiency and emission of exhaust gases when crambe biodiesel and diesel oil are used in a diesel-cycle internal combustion engine-generator, with different levels of resistive loads. A diesel-cycle engine generator was used, with 7.36 kW (10 cv) of power and 5.5 kVA/5.0 kW of nominal power, with monophasic output tension of 120/240 V. The used fuels were crambe biodiesel (B100) and diesel oil (B0). Nominal resistive loads applied ranged between 1.0 kW and 5.0 kW. In order to quantify the emission of gases, fuel quality and emission analyzer were used. Crambe biodiesel׳s data for specific consumption and efficiency of energetic conversion proved to be statistically equal to those of diesel. With the usage of crambe biodiesel there was a significant reduction in the analyzed exhausted gases.

Alkyl polycyclic aromatic hydrocarbons emissions in diesel/biodiesel exhaust

Polycyclic aromatic hydrocarbons (PAHs) are widely studied in environmental matrices, such as air, water, soil and sediment, because of their toxicity, mutagenicity and carcinogenicity. Because of these properties, the environmental agencies of developed countries have listed sixteen PAHs as priority pollutants. Few countries have limits for these compounds for ambient air, but they only limit emissions from stationary and mobile sources and occupational areas. There are several studies to specifically address the 16 priority PAHs and very little for the alkyl PAHs. These compounds are more abundant, more persistent and frequently more toxic than the non-alkylated PAHs, and the toxicity increases with the number of alkyl substitutions on the aromatic ring. In this study, a method was developed for the analysis of PAHs and alkyl PAHs by using a GC–MS and large injection volume injection coupled with program temperature vaporisation, which allows for limits of detection below 1.0 ng μL−1. Several variables were tested, such as the injection volume, injection velocity, injector initial temperature, duration of the solvent split and others. This method was evaluated in samples from particulate matter from the emissions of engines employing standard diesel, commercial diesel and biodiesel B20. Samples were collected on a dynamometer bench for a diesel engine cycle and the results ranged from 0.5 to 96.9 ng mL−1, indicating that diesel/biodiesel makes a significant contribution to the formation of PAHs and alkyl PAHs.

Assessment of the use of oxygenated fuels on emissions and performance of a diesel engine

Requirements as torque, power, specific fuel consumption and emitted compounds are highly influenced by the chemical composition of the fuel being burned. Thus, the aim of this study was to assess the use of oxygenated fuels on emissions of NOx, CO, HC, CO2 and particle number and size distribution (11.5<Da<365.2nm). In this paper a cycle diesel engine coupled to a dynamometer bench was used, where three types of fuels were employed, B5 (diesel with 5% of biodiesel); B5E6 (ternary composition containing 89% diesel, 5% of biodiesel and 6% of ethanol); and B100 (100% of biodiesel). The performance of a diesel engine was also evaluated to see the impact of the oxygenated fuels in this kind of engine. The use of ethanol with high latent heat of vaporization and low cetane number added to the binary blend (B5) shown an increase in the HC emissions and a reduction in NOx emissions when compared to B5. The use of pure biodiesel (B100) with high oxygen content showed a reduction in the HC emissions, but presented the highest emissions for both NOx and particle number of smaller diameter among the studied fuels. The use of more oxygenated fuels reduced the power output and increased the fuel consumption, but the exergy analysis showed that the energy efficiency of these fuels could be considered similar to the B5 fuel.

10302 高速ディーゼル機関の燃焼に及ぼすエマルション燃料,EGR,燃料噴射制御の効果

The use of emulsified fuel and EGR(Exhaust gas recirculation) system are effective methods to reduce NOx emission from diesel engines. In this paper, the authors studied on combustion and emission characteristics of the high speed, naturally aspirated, 4 stroke cycle diesel engine using emulsified fuel (EF, Gas oil(GS)80% + Water20%) and EGR(30%EGR ratio). And the effect of fuel injection control on combustion was investigated. The findings are the following: (1) Advancing main fuel injection timing at EGR operation using emulsified fuel, NOx, thermal efficiency and smoke are increased but CO is low. (2) Delaying pre-injection timing at EGR operation using emulsified fuel, NOx, thermal efficiency and smoke are low but CO is high.

Thermodynamic model and optimization of a miller cycle applied on a turbocharged diesel engine

A new thermodynamic model for turbocharged diesel engines is developed for Miller cycle analysis and optimization. The effects of turbocharger efficiency, Miller degree, combustion mode, and air fuel ratio on engine efficiency, power, and NOx emissions are analyzed by the model. Engine performance is optimized by the thermodynamic model under the constraints of maximum cylinder pressure and NOx emissions. Although the Miller cycle is beneficial for NOx emission control, it has adverse effects on engine thermal efficiency and power without parameter redesign. Turbocharger efficiency is a key factor in highly boosted Miller cycle diesel engines. The trade-off relationships among thermal efficiency, break mean effective pressure, and NOx emissions can be improved remarkably by highly efficient turbochargers. Measures with high geometric compression ratio and boost pressure and intensified Miller degree must be applied to reduce NOx emissions and improve thermal efficiency simultaneously. The results provide guidance in designing a Miller cycle system for turbocharged diesel engines.

A quasi-dimensional three-zone combustion model of the Diesel engine to calculate performances and emission using the Diesel-ethanol dual fuel

In the present study, develop the multi zone thermodynamic model for the simulation of a small diesel engine operating on the mixture of diesel and ethanol and comparing results with an experiment. This paper discussed analytically and provides data of nitrogen oxide and performance parameters such as power, speci20 Paramust Juntarakod and Thanakom Soontornchainacksaeng fic fuel consumption and thermal efficiency, indicated mean effective pressure. For this purpose, quasi-dimensional phenomenological three zone combustion process (unburned, adiabatic core region and boundary layer gas) has been modeled based on equilibrium constants method with MATLAB program to calculate the mole fractions of 11 combustion products when the new equilibrium constants function developed by Gill which are lowly-highly temperature dependent. To compute diesel engine cycles, zero-dimensional compression and expansion model have given by Ferguson and developed with new assumptions. These results involve various combination sequence effects of compression ratio (23-25), equivalence ratio (0.8-0.9), burn duration angle (60-70 CA) and engine speed (1000-1500 rpm) which volume fraction of fuel compositions (10-30% ethanol) (Diesel-Ethanol blend). The results of the study as the power was calculated by this method are the error range within around 5% or 0.5 kW from the maximum experiment results. The specific fuel consumption was less than 5% or 15-20 g (Fuel)/kW-hr from experiment results. The resulted show that nitrogen oxide has changed very little, corresponding results of various sequence effects. The performance parameters were changed with varying engine computing conditions. Maximum performance parameters be raised by increases the engine speed and equivalence ratio, its can increase the thermal efficiency are approximately value 15-20%.

Influence of port-inducted ethanol or gasoline on combustion and emission of a closed cycle diesel engine

After most CO2 is removed from exhaust gas by aqueous KOH in the CO2 absorber, the exhaust gas is re-circulated and mixed with a fresh oxygen charge to constitute a CCDE (closed cycle diesel engine) system. This study then improved the combustion and emissions of the diesel engine in the CCDE system using diesel fuel as main fuel with ethanol or gasoline of various energy share ratios inducted into the inlet port. Isothermal lines and velocity distributions in the engine cylinder from the numerical results are used to explain the measured emission results from the diesel engine in the CCDE system with port-inducted fuel. The CCDE system effectively decreases smoke, NOx, and CO2 before the CO2 absorber using port-inducting ethanol or gasoline. In addition, the experimental results are consistent with the numerical results for the operating engine.

Modelling and simulation of a bio-fuelled conventional engine

In the present work, a simulation model based on two different zones of combustion in compression ignition (CI) engines has been modified to predict the performance of a four-stroke CI engine. The modified model for the calculation of closed cycle of a four-stroke diesel engine is presented and applied for its operation with vegetable oil (Jatropha), which is considered as promising bio-fuels now a days. For the local temperature and cylinder pressure calculations, the mass and state equations are applied in each zone. The effect of fuel injection pressure and advance angle of fuel injection point on the brake thermal efficiency, brake-specific fuel consumption and nitric oxide emission has been analysed. The results from a computer program are compared and verified with the corresponding measurements from an experimental investigation conducted on the test bed. A good synchronisation is observed between the model's prediction and the available theoretical and experimental results. Engineering equation solver has been used as the programming input to the model.

Research of characteristics of working cycle of high-speed diesel engine operating on biofuels RME–E and D–RME–E. Part 2. Indicators and characteristics of heat release in diesel cylinder

This paper presents material about using two-component RME–E and three-component D–RME–E biodiesels in high-speed diesel engines. The results of the analysis of fuel injection parameters described in Part I of this scientific paper –&nbsp;Research of characteristics of working cycle of high-speed diesel engine operating on biofuels RME–E and D–RME–E. Part 1. Indicators of fuel injection system and indicative process&nbsp;– allow conducting a coherent research of heat release in the cylinder of diesel engines transferred from operation on mineral diesel D to mixed biodiesels containing E. Effects of increased ethanol E in the biodiesel of 1A41 diesel engine have been analysed in a wide range of loads, ranging from 0.25 to 1.0&nbsp;Penom.&nbsp;It was found that the result of the transfer from two-phase heat release to one-phase heat release is an increase in the fuel's economy of the engine for every 10% increase of E in the fuel (increase of indicative process efficiency makes up 0.4÷0.5%). Dependency of heat release and nitrogen oxide emissions in the exhaust gases remains the same for mineral diesel, RME–E and D–RME–E. Indicators of cyclic stability of the diesel engine, operating on biodiesels containing E ≤ 30%, did not exceed those that are common for diesel engines operating on mineral diesel. First Published Online: 11 Oct 2013

A Comparative Analysis of Different Cycle Diesel Engine Based on Three-Dimensional Simulation

The thermodynamic cycle analysis of diesel engines using the engine cycle simulation programs is feasible. The comparison of dual and LIVC miller cycles engine fueled with ED10 diesel/ethanol blends on temperature and emissions are investigated by simulation. From the comparison, +0.85 EIVC miller cycle is a selection for an optimizing point of miller cycle ratio, i.e, the intake valve timing of the engine is good for NO emission, SOOT emission and the engine power output. The difference of EIVC and LIVC miller cycle was studied. The results show the tendency of performance with EIVC miller cycle is similar to that of LIVC miller cycle. But the peak cylinder combustion temperature of EIVC miller cycle become lower relative to LIVC miller cycle, which lead to slightly lower NO emission and slightly higher SOOT emission for EIVC miller cycle.

Research of characteristics of working cycle of high-speed diesel engine operating on biofuels RME–E and D–RME–E. Part 1. Indicators of fuel injection system and indicative process

Abstract The article provides the results of an analyses of the characteristics of fuel injection system as well as the processes indicated in diesel engines 1A41 and F2L511, transferred from working with mineral diesel to working with rapeseed methyl ester–ethanol (RME–E) and mineral diesel fuel–rapeseed methyl ester–ethanol (D–RME–E). In biofuel, ethanol takes a part of 10÷40%. It was found that the E part in the fuel causes a lag of fuel injection of 2÷6 CA (greater values of fuel injection lag are common for partial engine loads and greater amount of E in fuel) that does not occur with mineral diesel fuel or RME. The analysis shows how a lag of fuel ignition limits the dynamic parameters (P max, (d p/d ϕ)max) of the cycle and specific emission of nitric oxides (eNOx) in exhaust gas. It is possible to convert diesel engines, operating on D to ethanol-containing biofuels without adjusting the fuel injection system parameters. At the same time, it is necessary to increase residual pressure in high-pressu...