Visual Study of Influence of Combustion Chamber Configurations on Fuel-Air Mixing Process in D.I. Diesel Engine Using Liquid-Liquid Injection Technique

In order to investigate the influence of spray position on fuel air mixing quality, three-dimensional numerical simulation of the working process of a heavy-duty diesel was conducted. To quantitatively study the mechanism of the effect of spray position on fuel air mixing process, the deviation of spray centroid was introduced to describe the spray position change in combustion chamber. The results show that the gas intake swirl can affect the spatial distribution of spray in combustion chamber under three directions in cylindrical coordinate, in which the circumferential distribution is affected most. It then can be concluded that the spray can be limited to the vicinity of the combustion chamber axis. Better spray position, which is more helpful for the process of fuel air mixing and combustion, can be achieved by using optimal swirl, so that the power performance will be improved.

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Investigation on the process of injection of commercial grade and blended fuel in a diesel engine

Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu ◽

10.33271/nvngu/2021-2/040 ◽

2021 ◽

pp. 40-46

Author(s):

F.I Abramchuk ◽

A.M Avramenko ◽

A.P Kuzmenko

Keyword(s):

Diesel Engine ◽

Combustion Chamber ◽

Fuel Injection ◽

Mixing Conditions ◽

Commercial Grade ◽

Injector Nozzle ◽

Fuel Flow ◽

Air Mixing ◽

Blended Fuel ◽

The Impact

Purpose. A computational valuation of the parameters of the process of commercial grade and blended fuel flow in the injector nozzle of a locomotive diesel engine, and its impact on spraying conditions in the combustion chamber. Methodology. The scientific investigation is based on using the technique of a comparative numerical experiment. Modern numerical methods in computational fluid dynamics are used for simulating fuel flow and spraying processes in the injector nozzle and combustion chamber. Findings. It was found that when working with commercial grade fuel with maximum pressure in the area of the injector well of 85MPa, the fuel flow velocity in the fuel injection nozzle hole reaches 434 m/s, whereas when working with fuel blended with alcohol the velocity decreases to 429 m/s (at a 25% alcohol concentration). Due to the lower pressure of saturated vapours of the blended fuel, as compared to that of commercial grade fuel, the fuel-air mixing conditions degrade at the operating duty being investigated. Originality. The investigation helped to study the impact of blended fuel composition on changes in the processes of its flow in the injector nozzle, and on the injection into the combustion chamber and the fuel-air mixing conditions. The study results helped to develop recommendations on ensuring effective ICE operation with blended fuel. Practical value. A change in the conditions of blended fuel spraying and fuel-air mixing should be taken into account when choosing effective fuel injection advance angles and fueling principles in order to ensure high ICE economic and ecological performance.

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Numerical Modeling Of The Ignition Initiation In The Scramjet Combustion Chamber Via Detonation

Siberian Journal of Physics ◽

10.54362/1818-7919-2016-11-4-33-44 ◽

2016 ◽

Vol 11 (4) ◽

pp. 33-44

Author(s):

Igor Bedarev ◽

Valentin Temerbekov ◽

Aleksandr Fedorov ◽

Kristina Rylova

Keyword(s):

Numerical Modeling ◽

Detonation Wave ◽

Combustion Chamber ◽

Wave Interaction ◽

Kinetic Scheme ◽

Reacting Flow ◽

Mixing Process ◽

Detonation Tube ◽

Cellular Detonation ◽

Air Mixing

The paper studies of the cellular detonation wave interaction with supersonic reacting flow in the scramjet combustion chamber. Comparing the flow fields for the details and the reduced chemical kinetics models is allowed verifying the acceptability of the proposed simplified kinetic scheme. The possibility of using pulsating detonation for the ignition intensification in the scramjet combustion chamber is shown. Calculation of the detonation wave interaction with nonpremixed hydrogenair mixture is made. The ability to influence on the hydrogen-air mixing process by means of detonation tube is detected. The effect of tube sizes to intensification of hydrogen air mixing in the flow at channel with a cavity is calculated.

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Relationship Between Visible Spray Observations and DI Diesel Engine Performance

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.1288705 ◽

2000 ◽

Vol 122 (4) ◽

pp. 596-602

Author(s):

Takashi Watanabe ◽

Susumu Daidoji ◽

Keshav S. Varde

Keyword(s):

Diesel Engine ◽

Combustion Chamber ◽

Swirling Flow ◽

Direct Injection ◽

Engine Performance ◽

Design Parameters ◽

Bench Test ◽

Injection Technique ◽

Bench Study ◽

Di Diesel Engine

This investigation was conducted to enhance understanding of combustion in a direct injection (DI) diesel engine with square combustion chamber. The investigation included a bench study of spray and its interaction with the chamber and correlation with engine performance. The bench study was conducted by using a liquid injection technique (LIT). The technique relies on the use of instantaneous photo images of emulsified fuel spray patterns to deduce spray behavior. It captures spray images in forced swirling flow on a positive film, which was used to deduce fuel-air mixing by scattering radiation technique. Three different chamber configurations, with different ratios of arc radius (r) to inscribed circle radius (R), and several spray deflecting angles were used in the study. The best parameters were found to be a deflecting angle of about 30 deg and a ratio of r/R of about 0.65. The results of the bench test were used to compare engine performance at similar design parameters. The engine performance was found to be superior at the above values of r/R and the deflecting angle. Engine exhaust of NOx and exhaust smoke were found to be lower at these design parameters. The experimental technique of using emulsified spray with LIT can be used qualitatively to evaluate effects of combustion chamber and fuel system design variables on engine performance. [S0742-4795(00)00104-6]

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Numerical Simulation of the Effects of the Nozzle Parameters on In-Cylinder Fuel and Air Mixing Process

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.401-403.218 ◽

2013 ◽

Vol 401-403 ◽

pp. 218-221

Author(s):

Qi Liu ◽

Guang Yao Ouyang ◽

Shi Jie An ◽

Yu Peng Sun

Keyword(s):

Numerical Simulation ◽

Diesel Engine ◽

Fuel Injection ◽

Combustion Model ◽

Engine Fuel ◽

Three Dimension ◽

Mixing Process ◽

Fuel Injector ◽

Injection Process ◽

Air Mixing

In order to study the injection property of diesel engine fuel injector, the three-dimension combustion model of TBD620 diesel engine is constructed on the AVL Fire software platform. A numerical simulation of the two injectors’ fuel injection process at different load conditions has been done. The influence on fuel and air mixing process is analyzed. The results show that the special injector has a good performance at low load, but the standard injector is more favorable for fuel and air fully mixing at high load.

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