scholarly journals Analysis on Pattern of Heat Release Rate in Two-Stroke Slow Speed Diesel Engine (2nd Report: Prediction of the Combustion Process)

2003 ◽  
Vol 38 (5) ◽  
pp. 303-308
Author(s):  
Takeshi Imahashi ◽  
Eiji Tomita ◽  
Sadami Yoshiyama ◽  
Kouji Moriyama
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Combustion Process ◽  
Slow Speed

scholarly journals Analysis on Pattern of Heat Release Rate in Two-Stroke Slow-Speed Diesel Engine

2003 ◽  
Vol 38 (4) ◽  
pp. 248-255
Author(s):  
T. Imahashi ◽  
E. Tomita ◽  
S. Yoshiyama ◽  
K. Moriyama
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Slow Speed

Experimental and Theoretical Optimization of Combustion Chamber and Fuel Distribution for the Low Emission DI Diesel Engine

2001 ◽  
Author(s):  
Yoshiyuki Kidoguchi ◽  
Michiko Sanda ◽  
Kei Miwa
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Combustion Chamber ◽  
Heat Release Rate ◽  
Release Rate ◽  
Combustion Process ◽  
Mixture Distribution ◽  
Initial Mixture ◽  
Injection Timing ◽  
Initial Heat

Abstract This study investigated the effect of combustion chamber geometry and initial mixture distribution on combustion process in a direct-injection diesel engine by means of experiment and CFD calculation. The high squish combustion chamber with squish lip could produce simultaneous reduction of NOx and particulate emissions with retarded injection timing in the real engine experiment. According to the CFD computation, the high squish combustion chamber with central pip is effective to continue combustion under the squish lip until the end of combustion and the combustion region forms rich and high turbulence atmosphere, which reduces NOx emissions. This chamber can also reduce initial burning because combustion continues under the squish lip. The CFD computation is also carried out in order to investigate the effect of initial mixture distribution on combustion process. The results suggest that mixture distribution affects the history of heat release rate. When fuel is distributed in the bottom or wide region in the combustion chamber, burned gas tends to spread to the cavity center and initial heat release rate becomes high. On the contrary, the high squish combustion chamber with central pip produces lower initial heat release rate because combustion with local rich condition continues long under the squish lip. Diffusion burning is promoted by high swirl motion in this chamber with keeping lower initial heat release rate.

Prediction of the effect of injection parameters on NOx emission and burning quality in the direct injection diesel engine using a modified multizone model

1998 ◽  
Vol 212 (5) ◽  
pp. 427-436 ◽  
Author(s):  
H Salem ◽  
S. H. El-Bahnasy ◽  
M Elbaz
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Combustion Process ◽  
Injection Pressure ◽  
Cylinder Pressure ◽  
Injection Parameters ◽  
Multizone Model ◽  
Engine Power

Combustion process in a quiescent chamber diesel engine is modelled using a multizone model. This model divides the cylinder charge into two zones, namely the unburnt zone (surrounding air) and the burnt zone (fuel spray with entrained air). The burnt zone is subdivided into 16 concentric sprays, instead of only eight sprays as in previous work, each one with its own temperature and composition. Liquid fuel, fuel vapour, air and products of combustion are assumed to be present in each zone. Real gas relations are used to calculate the properties of the mixture while products of combustion are assumed to be in chemical equilibrium at local temperature. The extended Zeldovich mechanism is used to predict the NO x formation. The cylinder pressure, temperature, heat release rate, NO x rate and concentration are calculated. For different injection pressures, injection advance angles and different fuel orifice hole diameters, the results show that the model can predict the measured cylinder pressure with high accuracy but it predicts the measured heat release rate and NO x emission rate with moderate accuracy. In addition, the effect of injection parameters on the NO x emission and engine power is predicted and it has been shown that NO x emission can be reduced without noticeable loss of engine power. This can be done by appropriate choice of injection pressure, injection advance angle and fuel nozzle hole diameters.

scholarly journals Combustion and Performance Study of Low-Displacement Compression Ignition Engines Operating with Diesel–Biodiesel Blends

2020 ◽  
Vol 10 (3) ◽  
pp. 907 ◽  
Author(s):  
Guillermo Valencia Ochoa ◽  
Carlos Acevedo Peñaloza ◽  
Jorge Duarte Forero
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Palm Oil ◽  
Heat Release Rate ◽  
Release Rate ◽  
Sunflower Oil ◽  
Combustion Process ◽  
Cylinder Pressure ◽  
Emission Analysis ◽  
Biodiesel Blends

This study investigated the influence of different biodiesel blends produced from residual sunflower oil and palm oil from agroindustry liquid waste on the characteristics of the combustion process, performance, and emissions in a single-cylinder diesel engine. For the analysis of the combustion process, a diagnostic model was developed based on the cylinder pressure signal, which allows the calculation of the heat release rate, the accumulated heat rate, and the temperature in the combustion chamber. This is to assess the influence of these parameters on engine emissions. The experiments on the diesel engine were carried out using five types of fuel: conventional diesel, two biodiesel blends of residual palm oil (PB5 and PB10), and two biodiesel blends formed with palm oil and sunflower oil residues (PB5SB5 and PB10SB5). The engine was running in four different modes, which covered its entire operating area. Experimental results show that the in-cylinder pressure curves decrease as the percentage of biodiesel in the fuel increases. Similarly, the results showed a decrease in the heat release rate for biodiesel blends. The diagrams of the accumulated heat release curves were larger for fuels with higher biodiesel content. This effect is reflected in the thermal efficiency of biodiesel blends since the maximum thermal efficiencies were 29.4%, 30%, 30.6%, 31.2%, and 31.8% for PB10SB5, PB5SB5, PB10, PB5, and diesel, respectively. The emission analysis showed that the blends of biodiesel PB5SB5 and PB10SB allowed a greater reduction in the emissions of CO, CO2, HC, and opacity of smoke in all the modes of operation tested, in comparison with the blends of biodiesel PB5 and PB10. However, NOx emissions increased. In general, biodiesel with the percentage of residual sunflower oil does not cause a significant change in the combustion process and engine performance, when compared to biodiesel that includes only residual palm oil.

Combustion and Emission Characteristics of Dual Fuel Engine for Different Parameters

2021 ◽  
Vol 13 (4) ◽  
Author(s):  
Jianjun Zhu ◽  
Peng Li ◽  
Yufeng Xie ◽  
Xin Geng
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Heat Release Rate ◽  
Compression Ratio ◽  
Release Rate ◽  
Emission Characteristics ◽  
Soot Emission ◽  
Cylinder Pressure ◽  
Fuel Delivery ◽  
Soot Emissions

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%.

Combustion Characteristics of Single Cylinder Diesel Engine Fueled with Blends of Thumba Biodiesel as an Alternative Fuel

2019 ◽  
Vol 969 ◽  
pp. 451-460
Author(s):  
Manpreet Singh ◽  
Mohd Yunus Sheikh ◽  
Dharmendra Singh ◽  
P. Nageswara Rao
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Heat Release Rate ◽  
Diesel Fuel ◽  
Release Rate ◽  
Mass Fraction ◽  
Pressure Rise ◽  
Cylinder Pressure ◽  
Gas Temperature ◽  
Edible Vegetable Oil

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.

Simultaneous Imaging of OH* Chemiluminescence and Flame Luminosity of Diesel and Biodiesel Spray Combustion

2011 ◽  
Author(s):  
Ji Zhang ◽  
Tiegang Fang
Keyword(s):  
Ambient Temperature ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Soot Formation ◽  
Combustion Process ◽  
Spray Combustion ◽  
Chemiluminescence Intensity ◽  
High Temperature Reaction ◽  
The Impact

The research on the spray combustion of diesel and biodiesel is vital to the understanding of emission formation and optimal utilization of fuel. This paper studies the biodiesel and diesel spray combustion in a constant volume chamber under different simulated diesel engine conditions. The ambient temperature at fuel injection varied from 800K to 1200K, while the ambient oxygen concentration was maintained at 21%. Simultaneous high speed imaging of OH* chemiluminescence and flame luminosity was employed to visualize the whole combustion process. Heat release rate was analyzed based on the measured combustion pressure. The apparent heat release rate analysis shows that biodiesel has a shorter ignition delay time than diesel, and biodiesel has a smaller cumulative heat release value due to its lower heating value. The overlaying image of OH* chemiluminescence and flame luminosity clearly identifies the high temperature reaction regions and soot formation regions. The line-of-sight images agree with the published observation that the hydroxyl radical is formed on the lean side of the flame edge. Decreasing ambient temperature greatly reduces the OH* chemiluminescence intensity of the diesel combustion, while the impact is smoother and milder for biodiesel combustion. Biodiesel shows a significantly lower level of flame luminosity than diesel under all conditions. These combined observations lead to a speculation that the soot oxidation process may serve as an important contributor to OH* chemiluminescence intensity for late stage combustion, and biodiesel shows a tendency to produce less soot than diesel under the investigated conditions.

Sign in / Sign up

Export Citation Format

Share Document