Effects of λ on the Combustion Characteristics of HCCI Engine Fueled with N-Butanol

2015 ◽  
Vol 1092-1093 ◽  
pp. 508-511
Author(s):  
Jia Wang Zhou ◽  
Chun Hua Zhang ◽  
Gang Li ◽  
Ye Chun Shen

The combustion characteristics of an HCCI engine fueled with n-butanol were investigated on a modified two-cylinder, four stoke diesel engine. The experiments were conducted on the HCCI engine with λ of 2.0, 2.5 and 3.0, and the intake air temperature and engine speed were kept at 140 °C and 1000rpm, respectively. Effects of λ on combustion characteristics including in-cylinder pressure rise rate, heat release rate, CA05 and combustion duration of HCCI combustion engine are discussed in details based on the recorded in-cylinder pressure. The results indicate that in-cylinder pressure and the rate of pressure rise both decrease with the increase of λ, the maximum heat release rate also decreases with the increase of λ but occurs at late crank angles. In addition, as λ increases, the combustion phasing retards and combustion duration becomes longer.

2014 ◽  
Vol 700 ◽  
pp. 651-654 ◽  
Author(s):  
Gang Li ◽  
Chun Hua Zhang ◽  
Ye Chong Shen ◽  
Ya Chong Shen ◽  
Jia Wang Zhou

In order to study the influence of intake temperature on the combustion characteristics of HCCI engine fueled with n-butanol, the 2nd cylinder of a water-cooled, naturally aspirated and double-cylinders diesel engine was converted into HCCI combustion mode. The cylinder pressure (P), rate of pressure rise (dp/dφ), heat release rate (dQ/dφ) and cycle-to-cycle variations (CCV) were compared and analyzed by bench tests under the conditions with different intake temperatures at engine speed of 1000r/min, excess air coefficient of 2.5. The experiment results show that the peak pressure (Pmax), the peak rate of pressure rise and maximum heat release rate tend to rise and the peak arrives in advance with the increase of intake temperature. As the intake temperature rises, the coefficient of variation for Pmaxreduces and combustion stability increases.


2019 ◽  
Vol 969 ◽  
pp. 451-460
Author(s):  
Manpreet Singh ◽  
Mohd Yunus Sheikh ◽  
Dharmendra Singh ◽  
P. Nageswara Rao

The rapid rise in energy requirement and problem regarding atmosphere pollutions, renewable biofuels are the better alternative choice for the internal combustion engine to partially or totally replace the pollutant petroleum fuel. In the present work, thumba (Citrullus colocynthis) non-edible vegetable oil is used for the production of biodiesel and examine its possibility as diesel engine fuel. Transesterification process is used to produce biodiesel from thumba non-edible vegetable oil. Thumba biodiesel (TBD) is used to prepare five different volume concentration (blends) with neat diesel (D100), such as TBD5, TBD15, TBD25, TBD35 and TBD45 to run a single cylinder diesel engine. The diesel engine's combustion parameter such as in-cylinder pressure, rate of pressure rise, net heat release rate, cumulative heat release, mean gas temperature, and mass fraction burnt analyzed through graphs and compared all thumba biodiesel blends result with neat diesel fuel. The mass fraction burnt start earlier for thumba biodiesel blends compared to diesel fuel because of less ignition delay while peak in-cylinder pressure, maximum rate of pressure rise, maximum net heat release rate, maximum cumulative heat release, and maximum mean gas temperature has found decreased results up to 1.93%, 5.53%, 4.11%, 4.65%, and 1.73% respectively for thumba biodiesel.


Author(s):  
Avinash Kumar Agarwal ◽  
Atul Dhar

The methyl esters of vegetable oils known as biodiesel are becoming increasingly popular because of their low environmental impact and potential as a green alternative fuel for diesel engines. Methyl ester of rice-bran oil (RBOME) is prepared through the process of transesterification. In the present investigation, experiments have been carried out to examine the performance, emission, and combustion characteristics of a direct-injection transportation diesel engine running with diesel, 20% blend of rice-bran oil (RBO), and 20% blend of RBOME with mineral diesel. A four-stroke, four-cylinder, direct-injection transportation diesel engine (MDI 3000) was instrumented for the measurement of the engine performance, emissions, in-cylinder pressure-crank angle history, rate of pressure rise, and other important combustion parameters such as instantaneous heat release rate, cumulative heat release rate, mass fraction burned, etc. A careful analysis of the performance, emissions, combustion, and heat release parameters has been carried out. HC, CO, and smoke emissions for RBO and RBOME blends were lower than mineral diesel while NOx emissions were almost similar and brake specific fuel consumption (BSFC) was slightly higher than mineral diesel. Combustion characteristics were quite similar for the three fuels.


2021 ◽  
Vol 25 (Spec. issue 1) ◽  
pp. 101-110
Author(s):  
Erdinc Vural ◽  
Serkan Ozel ◽  
Salih Ozer

In this study, piston and valve surfaces of a Diesel engine to improve exhaust emis?sion and engine performance values, NiCr with bond coat and without bond coat with Cr2O3, Al2O3+13%TiO2, Cr2O3+25%Al2O3 coatings were coated using plasma spray method. By examining the micro-structures of the coating materials, it was observed that a good coating bond is formed. In this study, unlike other coating applications, two different and proportions of specific ceramic powders were coated on the combustion chamber elements, mounted on a Diesel engine, and their effects on engine performance and emissions were tested on the engine dynamometer. For this purpose, the internal combustion engine was operated at 1400, 1700, 2000, 2300, 2600, 2900, and 3200 rpm engine speeds and engine power, engine torque, in-cylinder pressure changes and heat release rate values were recorded. In this study, the that results were obtained by comparing thermal barrier coated engine with standard engine. An increase of 14.92% in maximum engine power, 12.35% in engine torque, 13% in-cylinder pressure, heat release rate by 4.5%, and brake thermal efficiency by 10.17% was detected, while brake specific fuel consumption decreased by 14.96%.


Author(s):  
Shailendra Sinha ◽  
Avinash Kumar Agarwal

The methyl esters of vegetable oils, known as biodiesel are becoming increasingly popular because of their low environmental impact and potential as a green alternative fuel for diesel engines. They do not require significant modification in existing engine hardware. Methyl ester of rice bran oil (ROME) is prepared through the process of transesterification. Previous research has shown that ROME has comparable performance, lower bsfc in comparison to diesel. There was reduction in the emissions of CO, HC, and smoke but NOx emissions increased. In the present research, experimental investigations have been carried out to examine the combustion characteristics of a direct injection transportation diesel engine running with diesel, and 20% blend of ROME with diesel. A four-stroke, four-cylinder, direct-injection transportation diesel engine (MDI 3000) was fully instrumented for the measurement of combustion pressure, rate of pressure rise and other combustion parameters such as instantaneous heat release rate, cumulative heat release rate, mass fraction burned etc. Tests were performed at different loads ranging from no load to 100%, at constant engine speed. No engine hardware modification was carried out for the present study. A careful analysis of combustion and heat release parameters has been carried out, which gives precise information about the in-cylinder combustion of rice bran oil based biodiesel vis-a`-vis mineral diesel.


2020 ◽  
pp. 146808742093460
Author(s):  
Khawar Mohiuddin ◽  
Heesun Kwon ◽  
Minhoo Choi ◽  
Sungwook Park

Particle number emissions need to be monitored and controlled in order to comply with the latest emission legislations for gasoline and diesel engines. This research focuses on performance and emission analysis of a light-duty diesel engine with various injector hole numbers. A 500cc single-cylinder diesel engine was used for this purpose, and injectors with hole numbers varying from 7 to 10 were analyzed. Different operating conditions were selected to test the engine at all types of loading conditions. Start of injection and exhaust gas recirculation swings were carried out at all the test cases to see the variation of particle number and other emissions. Increasing injector hole number from 7 to 9, in-cylinder pressure heat release rate and combustion duration increased while ignition delay was shortened. Soot-NOx and ISFC-NOx trade-offs also improved with decreasing hole diameter for these hole numbers. Particle number emissions reduced significantly with increasing hole number. However, the 10-hole injector exhibited a different behavior than the other injectors. For low loading case, cylinder pressure and heat release rate were higher than those of the 9-hole injector but for medium and high loading cases, in-cylinder pressure, heat release rate, and combustion duration of the 10-hole injector were found to be lesser than the 9-hole injector. For medium and high loading cases, particle number emissions from the 10-hole nozzle also increased as compared to the 9-hole injector. Optical engine investigation revealed a higher flame-flame interference in case of the 10-hole injector which resulted in degraded combustion performance and higher particle number emissions.


2008 ◽  
Vol 12 (1) ◽  
pp. 85-102 ◽  
Author(s):  
Miroljub Tomic ◽  
Slobodan Popovic ◽  
Nenad Miljic ◽  
Stojan Petrovic ◽  
Milos Cvetic ◽  
...  

In this paper a simplified procedure of an internal combustion engine in-cylinder pressure record analysis has been presented. The method is very easy for programming and provides quick evaluation of the gas temperature and the rate of combustion. It is based on the consideration proposed by Hohenberg and Killman, but enhances the approach by involving the rate of heat transferred to the walls that was omitted in the original approach. It enables the evaluation of the complete rate of heat released by combustion (often designated as ?gross heat release rate? or ?fuel chemical energy release rate?), not only the rate of heat transferred to the gas (which is often designated as ?net heat release rate?). The accuracy of the method has been also analyzed and it is shown that the errors caused by the simplifications in the model are very small, particularly if the crank angle step is also small. A several practical applications on recorded pressure diagrams taken from both spark ignition and compression ignition engine are presented as well.


1997 ◽  
Vol 15 (6) ◽  
pp. 481-487 ◽  
Author(s):  
J.C. Jones

A sample of Sitka Spruce litter has been examined in a microcalo rimeter at temperatures up to 58°C, and kinetic parameters deduced from the re sults in a way which is explained step by step. The kinetic parameters were then used to predict the ignition temperature of the material in a field situation. Input to this calculation includes measured heat-release rate at incipient ignition of a different litter, reported independently.


Author(s):  
Jianjun Zhu ◽  
Peng Li ◽  
Yufeng Xie ◽  
Xin Geng

The effects of compression ratio and fuel delivery advance angle on the combustion and emission characteristics of premixed methanol charge induced ignition by Fischer Tropsch diesel engine were investigated using a CY25TQ diesel engine. In the process of reducing the compression ratio from 16.9 to 15.4, the starting point of combustion is fluctuating, the peak of in-cylinder pressure and the maximum pressure increase rate decrease by 44.5% and 37.7% respectively. The peak instantaneous heat release rate increases by 54.4%. HC and CO emissions are on a rising trend. NOx and soot emissions were greatly decreased. The soot emission has the biggest drop of 50%. Reducing the fuel delivery advance angle will make the peak of in-cylinder pressure and the peak of pressure rise rate increase while the peak of heat release rate decreases. The soot emission is negatively correlated with the fuel delivery advance angle. When the fuel delivery advance angle is 16° CA, the soot emissions increased the most by 130%.


2014 ◽  
Vol 1004-1005 ◽  
pp. 77-84 ◽  
Author(s):  
Zhen Lu Zhang ◽  
Dong Li Li ◽  
Wen Cai Xu ◽  
Ya Bo Fu ◽  
Rui Juan Liao

This work reports the flammability properties of Nanocomposites reinforced with silica and PTFE nanoparticles and toughened with an elastomeric ethylene-vinyl acetate (EVA). Through trial and simulation study of the flame retardant thermoplastic polymer and melting characteristics of PP in the combustion process.The study found that modified PP composites have good flame retardancy compared to PP in case of fire relatively.In the study,the melting characteristics of the thermoplastic polymer affected the mass loss rate in the combustion stage.Nanocomposites experienced low plastic mass loss compared with PP, this has been related to pyrolysis mechanism of polymer.In general,The polymers undergoing depolymerization will lead to a rapid volatilization and therefore experienced much less melting.The results showed that:total heat release of nanocomposites was higher than polypropylene, while the average heat release rate, the maximum heat release rate, the average effective heat of combustion, the average mass loss rate, the average specific extinction area, and other indicators were lower than polypropylene.


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