The Impact of Emissions and Fuel Economy Requirements on Fuel Injection System and Noise of HD Diesel Engines

The diesel fuel-injection system of ALCO DLW 251 engine consists of single cylinder injection pumps, delivery pipes, and fuel injector nozzles. Fuel injection into the combustion chamber through multi-hole nozzles delivers designed power and fuel efficiency. The two most important variables in a fuel injection system of a diesel engine are the injection pressure and injection timing. Proper timing of the injection process is essential for satisfactory diesel engine operation and performance. Injection timing needs to be optimised for an engine based on requirements of power, fuel economy, mechanical and thermal loading limitations, smoke and emissions etc. Since each of these requirements varies with the operating conditions, sometimes contrary to the requirements of the other parameters, the map of optimised injection timing can be very complex. The ALCO DLW 251 engine’s fuel injection pump is jerk type to permit accurate metering and timing of the fuel injected. The pump has a ported barrel and constant-stroke plunger incorporating a bottom helix for fuel delivery control with constant injection timing. From the point of view of good power and fuel economy, combustion should take place so that the peak firing pressure occurs at about 10–15° after TDC and is usually a few degrees after combustion starts. For this to happen, fuel should be injected at an appropriate time, depending on Injection delay and Ignition delay. Both these factors are dependent on the speed and load. Changing the operating point of the engine may change either one or both types of delay, altering the moment of start of combustion. Various researchers have shown that both the Injection and the Ignition delay are reduced as the engine speed is decreased resulting in advancement of injection timing at lower speeds (and loads). This condition will be corrected by varying the static injection timing, which can be achieved by providing a modified helix on the plunger to delay the start of fuel injection, for the lower speeds and loads. A new double helix (upper and lower helix) fuel injection pump for the ALCO DLW 251 16 V engine has been designed. The new fuel injection pump has been tested on the engine test cell at Research Designs & Standards Organisation and has shown an improvement of 1.2% in locomotive duty cycle fuel consumption. This paper describes the design & development of double helix fuel injection pump and discusses the engine tests completed to verify the projected improvements in fuel efficiency.

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Predicting Hydrocarbon Emissions From Direct Injection Diesel Engines

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.1456091 ◽

2002 ◽

Vol 124 (3) ◽

pp. 708-716 ◽

Cited By ~ 15

Author(s):

P. A. Lakshminarayanan ◽

N. Nayak ◽

S. V. Dingare ◽

A. D. Dani

Keyword(s):

Diesel Engines ◽

Fuel Injection ◽

Direct Injection ◽

Injection System ◽

Hydrocarbon Emissions ◽

Operating Parameters ◽

Fuel Injection System ◽

Lean Combustion ◽

Medium Speed ◽

Hc Emissions

Hydrocarbon (HC) emissions from direct injection (DI) diesel engines are mainly due to fuel injected and mixed beyond the lean combustion limit during ignition delay and fuel effusing from the nozzle sac at low pressure. In the present paper, the concept has been developed to provide an elegant model to predict the HC emissions considering slow burning. Eight medium speed engines differing widely in bores, strokes, rated speeds, and power were studied for applying the model. The engines were naturally aspirated, turbocharged, or turbocharged with intercooling. The model has been validated by collecting data on HC emission, and pressures in the cylinder and in the fuel injection system from the experimental engines. New coefficients for the correlation of HC with operating parameters were obtained and these are different from the values published earlier, based on single-engine experiments.

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Effects of Electronically Controlled Fuel Injection System (EFI) for Marine Diesel Engines

Marine Engineering ◽

10.5988/jime.45.974 ◽

2010 ◽

Vol 45 (Special) ◽

pp. 974-979 ◽

Cited By ~ 1

Author(s):

Kousuke Okazak ◽

Koji Takasaki ◽

Hiroshi Tajima ◽

Shintaro Shuto ◽

Satoshi Kawauchi ◽

...

Keyword(s):

Diesel Engines ◽

Fuel Injection ◽

Injection System ◽

Fuel Injection System ◽

Marine Diesel

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A Numerical Analysis of the Combustion and the Study of the Exhaust Gases Resulting therefrom in the Marine Engines

Revista de Chimie ◽

10.37358/rc.19.3.7033 ◽

2019 ◽

Vol 70 (3) ◽

pp. 929-933

Author(s):

Catalin Faitar ◽

Feiza Memet ◽

Nicolae Buzbuchi

Keyword(s):

Diesel Engines ◽

Internal Combustion Engines ◽

Fuel Injection ◽

Critical Factor ◽

Injection System ◽

Positive Contribution ◽

Combustion Gases ◽

Injection Process ◽

Marine Engines ◽

The Impact

Maritime University of Constanta, Faculty of Naval Electromechanics, 104 Mircea cel Batran Str., 900663, Constanta, Romania Combustion inside diesel engine cylinders is the critical factor that controls the emission and combustion gases. Fuel injection in the engine cylinder is the decisive factor in the combustion of diesel engines and, consequently, combustion can be effectively controlled if the fuel injection process is efficiently controlled. From this perspective, the simulation of the complex processes of fuel injection in diesel engines in various situations can make a positive contribution to the optimization of marine propulsion systems. Also, correct dimensioning of the injection system components and its optimization and, implicitly, the combustion parameters, can have positive results in the context of reducing the impact of combustion gases of internal combustion engines, on the greenhouse effect and global warming.

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