Application of biomethanol to advanced CI engines: a review

Author(s):  
Soo Young No
Keyword(s):  
2021 ◽  
pp. 146808742110183
Author(s):  
Jonathan Martin ◽  
André Boehman

Compression-ignition (CI) engines can produce higher thermal efficiency (TE) and thus lower carbon dioxide (CO2) emissions than spark-ignition (SI) engines. Unfortunately, the overall fuel economy of CI engine vehicles is limited by their emissions of nitrogen oxides (NOx) and soot, which must be mitigated with costly, resource- and energy-intensive aftertreatment. NOx and soot could also be mitigated by adding premixed gasoline to complement the conventional, non-premixed direct injection (DI) of diesel fuel in CI engines. Several such “dual-fuel” combustion modes have been introduced in recent years, but these modes are usually studied individually at discrete conditions. This paper introduces a mapping system for dual-fuel CI modes that links together several previously studied modes across a continuous two-dimensional diagram. This system includes the conventional diesel combustion (CDC) and conventional dual-fuel (CDF) modes; the well-explored advanced combustion modes of HCCI, RCCI, PCCI, and PPCI; and a previously discovered but relatively unexplored combustion mode that is herein titled “Piston-split Dual-Fuel Combustion” or PDFC. Tests show that dual-fuel CI engines can simultaneously increase TE and lower NOx and/or soot emissions at high loads through the use of Partial HCCI (PHCCI). At low loads, PHCCI is not possible, but either PDFC or RCCI can be used to further improve NOx and/or soot emissions, albeit at slightly lower TE. These results lead to a “partial dual-fuel” multi-mode strategy of PHCCI at high loads and CDC at low loads, linked together by PDFC. Drive cycle simulations show that this strategy, when tuned to balance NOx and soot reductions, can reduce engine-out CO2 emissions by about 1% while reducing NOx and soot by about 20% each with respect to CDC. This increases emissions of unburnt hydrocarbons (UHC), still in a treatable range (2.0 g/kWh) but five times as high as CDC, requiring changes in aftertreatment strategy.


2021 ◽  
Vol 104 (2) ◽  
pp. 003685042110209
Author(s):  
Zain Ul Hassan ◽  
Muhammad Usman ◽  
Muhammad Asim ◽  
Ali Hussain Kazim ◽  
Muhammad Farooq ◽  
...  

Despite a number of efforts to evaluate the utility of water-diesel emulsions (WED) in CI engine to improve its performance and reduce its emissions in search of alternative fuels to combat the higher prices and depleting resources of fossil fuels, no consistent results are available. Additionally, the noise emissions in the case of WED are not thoroughly discussed which motivated this research to analyze the performance and emission characteristics of WED. Brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) were calculated at 1600 rpm within 15%–75% of the load range. Similarly, the contents of NOx, CO, and HC, and level of noise and smoke were measured varying the percentage of water from 2% to 10% gradually for all values of loads. BTE in the case of water emulsified diesel was decreased gradually as the percentage of water increased accompanied by a gradual increase in BSFC. Thus, WED10 showed a maximum 13.08% lower value of BTE while BSFC was increased by 32.28%. However, NOx emissions (21.8%) and smoke (48%) were also reduced significantly in the case of WED10 along with an increase in the emissions of HC and CO and noise. The comparative analysis showed that the emulsified diesel can significantly reduce the emission of NOx and smoke, but it has a negative impact on the performance characteristics and HC, CO, and noise emissions which can be mitigated by trying more fuels variations such as biodiesel and using different water injection methods to decrease dependency on fossil fuels and improve the environmental impacts of CI engines.


2019 ◽  
Vol 141 (11) ◽  
Author(s):  
Jinlong Liu ◽  
Hemanth Kumar Bommisetty ◽  
Cosmin Emil Dumitrescu

Heavy-duty compression-ignition (CI) engines converted to natural gas (NG) operation can reduce the dependence on petroleum-based fuels and curtail greenhouse gas emissions. Such an engine was converted to premixed NG spark-ignition (SI) operation through the addition of a gas injector in the intake manifold and of a spark plug in place of the diesel injector. Engine performance and combustion characteristics were investigated at several lean-burn operating conditions that changed fuel composition, spark timing, equivalence ratio, and engine speed. While the engine operation was stable, the reentrant bowl-in-piston (a characteristic of a CI engine) influenced the combustion event such as producing a significant late combustion, particularly for advanced spark timing. This was due to an important fraction of the fuel burning late in the squish region, which affected the end of combustion, the combustion duration, and the cycle-to-cycle variation. However, the lower cycle-to-cycle variation, stable combustion event, and the lack of knocking suggest a successful conversion of conventional diesel engines to NG SI operation using the approach described here.


Author(s):  
Christopher Depcik ◽  
Sudarshan Loya ◽  
Anand Srinivasan

Future emission standards are driving the need for advanced control of both Spark (SI) and Compression Ignition (CI) engines. However, even with the implementation of cooled Exhaust Gas Recirculation and Low Temperature Combustion (LTC), it is unlikely that in-cylinder combustion strategies alone will reduce emissions to levels below the proposed standards. As a result, researchers are developing complex catalytic aftertreatment systems to meet these tailpipe regulations for both conventional and alternative combustion regimes. Simulating these exhaust systems requires fast and accurate models suitable for significant changes in inlet conditions. Most aftertreatment devices contain Platinum Group Metals because of their widely documented beneficial catalysis properties; examples include Diesel Oxidation Catalysts, Three-Way Catalysts and Lean NOx Traps. There are kinetic mechanisms available for each of these devices, but often they do not extrapolate well to other formulations. For example, Carbon Monoxide (CO) levels entering a catalyst are significantly different between an SI and CI engine. In addition, modifying engine control to utilize LTC operation can result in an increase in CO levels due to lower combustion efficiency. This adversely affects the conversion capabilities of a catalytic device through increased levels of CO inhibition. Finally, catalyst loading and metal dispersion differences between devices often prohibit a direct extension of kinetic constants. As a result, mechanisms often need recalibration for correct modeling capabilities. In order to begin creating a more predictive kinetic mechanism, this paper simulates CO oxidation as a function of different inlet concentration levels and metal loadings. While aftertreatment devices contain many reactions, modeling of one fundamental reaction is a first step to determine the feasibility of adaptive kinetics. In addition, research into the history of the CO oxidation mechanism over platinum illustrates a more accurate rate expression to utilize in deference to current modeling activities. The authors calibrate this expression to experimental data taking into account significant changes in inlet conditions, metal loading and dispersion values. Model fidelity is determined through the simulation of additional data not part of the initial calibration efforts. In addition, the paper discusses strengths and weaknesses of the model along with how other researchers can help foster adaptive kinetic development.


Energies ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 2043 ◽  
Author(s):  
Tiantian Yang ◽  
Tie Wang ◽  
Guoxing Li ◽  
Jinhong Shi ◽  
Xiuquan Sun

Fischer-Tropsch diesel fuel synthesized from coal (CFT) is an alternative fuel that gives excellent emission performance in compression ignition (CI) engines. In order to study the vibration characteristics, which are important for determining the applicability of the fuel, CFT-diesel blends were tested on a CI engine to acquire vibration signals from the engine head and block. Based on the FFT and continuous wavelet transformation (CWT) analysis, the influence of CFT on the vibration was studied. The results showed that the root mean square (RMS) values of the vibration signal decrease as the proportion of CFT in the blends increases. The CWT results indicated that the vibration energy areas motivated by the pressure shock of transient combustion were weak with increasing CFT proportion for the different frequency bands. The blend of 90% pure petro-diesel and 10% CFT registered the largest RMS value for piston side thrust response, and the RMS of high-frequency pressure oscillation response is greater than that of the main response of combustion, for FT30. Therefore, CFT has the potential to reduce the combustion vibration of the engine at all frequency bands, and there is a possibility that the proportion of blended fuel can be modified to satisfy the vibration characteristics requirements in different frequency bands.


2021 ◽  
Vol 850 (1) ◽  
pp. 012005
Author(s):  
Nikhil Muthu Kumar ◽  
Harsh Bhavsar ◽  
G Sakthivel ◽  
Mohammed Musthafa Feroskhan ◽  
K Karunamurthy

Abstract The introduction of the strict emissions norms is diverting the research for the development of new technologies which leads to the reduction of engine exhaust emissions. The usage of biodiesel in CI engine can enhance air quality index and protects the environment. Biodiesel can do an increment in the life of CI engines because it is clean-burning and a stable fuel when compared to diesel. Moreover, biogas has the potential to decrease both nitrogen oxides and smoke emissions simultaneously. Operating the engine in dual-fuel mode can provide lower emissions and a proper substitute for diesel. In this research, a modified CI Engine with single cylinder is used. Biogas is used as primary fuel and diesel, Mahua oil-diesel blend and Fish oil-diesel blend are used as secondary fuel. The effect of various secondary fuel blends on performance and emission characteristics in dual fuel engine are compared. In light of the performance and emission qualities it is reasoned that, utilization of the dual fuel mode in engine signifies the durability and lessens the harmful emissions from the engine with the exception of hydrocarbon and CO emissions. The excessive viscosity of fish oil and mahua oil prompts inconvenience in siphoning and spray attributes. The incompetent mixing of raw fish oil and raw mahua oil with diesel and biogas including air leads to incomplete combustion.


2021 ◽  
Vol 12 (4) ◽  
pp. 23-40
Author(s):  
Naresh Kumar Konada ◽  
K.N.S. Suma ◽  
B.B. Ashok Kumar

Increase in energy demand, stringent emission norms and depletion of oil resources led to the discovery of alternative fuels forinternal combustion engines. Many alternative fuels like alcohols, petroleum gas, and compressed natural gas have been alreadycommercialized in the transport sector. In the present work, Pongomia oil and Neem oil are blended with diesel and used as analternate fuel for CI engines. The Pongomia oil and Neem oil can be converted into bio diesel using a chemical process of trans- esterification.Different proportions of fuel blends have been produced by the process of blending bio diesel consisting of 10%, 15%, 20%, 25%, and 30% (B10, B15, B20, B25, B30). The fuel properties of each blend are determined. The load test along with smoke and exhaust gas analysis of 4- Stroke Diesel engine using the blends of Pongomia oil and Neem oil with diesel are done in this study. The performance parameters of an engine are calculated for different blends. The sustainability of using alternate fuels in Diesel engines, especially the potential use of Pongomia oil and Neem oil as biodiesel have been brought to the fore through this work and suitable blends of bio diesel is suggested from the results. Keywords: 4-Stroke Diesel Engine, Pongomia and Neem oil Bo diesel, Performance, Smoke and exhaust gas analysis.


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