Method for controlling wave phenomena in highpressure line of common rail of internal combustion engines

2020 ◽  
Keyword(s):  
Internal Combustion Engines ◽  
Fuel Injection ◽  
Internal Combustion ◽  
Common Rail ◽  
Combustion Engines ◽  
Multiple Injection ◽  
Multiple Injections ◽  
Fuel Supply ◽  
Injection Line ◽  
Wave Phenomena

The article presents an assessment of the dependence of the fuel supply on the wave phenomena in the highpressure line that occur during multiple injection. After injection, fluctuations in the fuel pressure in the fuel injection line occur, which significantly affect the cycle delivery and injection behavior of subsequent multiple injections. A promising design of a fuel rail is presented and a method for controlling wave phenomena in a highpressure line of a Common Rail is proposed. Keywords wave phenomena; multiple injection; Common Rail; electrohydraulic injector; fuel rail

On-Board Fuel Property Identification Method Based on High-Pressure Common Rail Pressure Signal

2014 ◽  
Vol 136 (3) ◽  
Author(s):  
Junfeng Zhao ◽  
Junmin Wang
Keyword(s):  
High Pressure ◽  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Common Rail ◽  
Combustion Engines ◽  
Rail Pressure ◽  
Fuel Property ◽  
Pressure Signal ◽  
Common Rail Pressure ◽  
Property Identification

This paper investigates the impact of fuel property variations on the common rail pressure fluctuation in high-pressure common rail (HPCR) system and explores the possibility of identifying the fuel types based on the measurement of rail pressure for internal combustion engines. Fluid transients, particularly the water hammer effect in a HPCR system, are discussed and the 1D governing equations are given. A typical HPCR system model is developed in GT-Suite with the injectors, three-plunger high-pressure pump, and pressure control valve being modeled in a relatively high level of detail. Four different fuels including gasoline, ethanol, diesel, and biodiesel are modeled and their properties including density, bulk modulus, and acoustic wave speed are validated against data in the literature. Simulation results are obtained under different conditions with variable rail pressures and engine speeds. To reduce the excessive rail pressure oscillation caused by multiple injections, only four main-injections are enabled in each engine revolution. The results show that the natural frequency of a common rail varies with the type of fuel filled in it. By applying the fast Fourier transform (FFT) to the pressure signal, the differences of fuel properties can be revealed in the frequency domain. The experiment validation is conducted on a medium-duty diesel engine, which is equipped with a typical HPCR system and piezo-electric injectors. Tests results are given for both pure No. 2 diesel and pure soybean biodiesel at different rail pressure levels and different engine speeds. This approach is proved to be potentially useful for fuel property identification of gasoline-ethanol or diesel-biodiesel blends on internal combustion engines.

Osady w tłokowych silnikach spalinowych

2020 ◽  
Author(s):  
Zbigniew Stępień
Keyword(s):  
Internal Combustion Engines ◽  
Fuel Injection ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Fuel Injector ◽  
Combustion Chambers ◽  
Deposit Formation ◽  
The Impact ◽  
Ci Engines ◽  
Engine Deposits

The undesirable deposits forming on the surfaces of various internal parts of reciprocating internal combustion engines and the systems operating in conjunction with them worsen during the operation of the engines and threaten their proper functioning. The deposits form as a normal result of the processes of fuel injection and creating and combusting the fuel–air mixture in engines. It was not investigated until the beginning of the 21st century, when extensive multi-directional research began not only to identify the causes of these deposits, the mechanisms behind their formation, and the factors leading to deposit growth, but also to determine the chemical composition of various groups of deposits. Such research became necessary because engines must comply with gradually tightening regulations on environmental protection, necessitating the introduction of increasingly complex engine designs and strategies for controlling the processes of precise and divided fuel injection into the combustion chambers and advanced algorithms for controlling the combustion processes according to the combustion system and the purpose of the engine. However, it became apparent that the co-functioning of the increasingly complex engine technologies and solutions, particularly of fuel injection systems, may be significantly disturbed by the deposits forming inside them. More and more complicated engine designs with tighter and tighter tolerances of the working parts necessitate the multi-directional testing of harmful deposits. An increasing number of factors affecting deposit formation are being identified, which leads to the development of increasingly complex classifications and subdivisions of deposits according to their type, composition, and form. At the same time, the search for lower emissions and greater engine efficiency is driving further mechanical changes in engines and vehicles. The higher temperatures and pressures connected with these changes are likely to impact the fuel being handled within the fuel and combustion systems. Such effects will inevitably cause the deposit chemistry and morphology to change. The size of the coke deposits produced may disturb the processes of fuel atomization, of filling the engine combustion chambers and swirling the charge, and in consequence may affect the efficiency of filling and the quality of the fuel–air mixture. These problems led to the development of a number of standardized and unstandardized methods for assessing the size of deposits. It was found that in the case of SI engines, the deposits that most endanger correct engine operation are those which are formed in the combustion chambers, on the inlet valves, inlet ducts, and fuel injector tips. The most common sign of deterioration caused by deposits is the loss over time of the performance, usability, and operational value which were originally declared by the manufacturer. In the case of CI engines, the most dangerous are coke (carbon) deposits formed on the external surfaces of the fuel injector nozzle tips and inside the injector nozzle orifices. In Europe, mandatory procedures for assessing the size of different coke deposits formed on different components in both SI and CI engines are being developed by the Coordinating European Council for the Development of Performance Tests for Transportation Fuels, Lubricants, and Other Fluids (CEC). The theoretical part of this publication reports the problems of the deposits produced in reciprocating internal combustion engines and their fuel systems. It discusses standard and non-standard engine test methods for both quantitative and qualitative assessment of deposits and presents the significance of the assessment methods which are currently used for the classification of deposits. The publication also presents the scope of application and the usefulness of methods for determining the threats posed to the functioning of an engine by various types of deposits and methods for identifying the causes of deposit formation, in particular those related to the composition of the fuels and lubricating oils used. The effects which fuel composition and the engine’s construction and operating parameters have on various engine deposits, the possible causes of deposit formation, and the importance of modern deposit control additives and high-technology solutions in counteracting this detrimental phenomenon are also all discussed. The experimental part presents the results of research carried out at the Oil and Gas Institute – National Research Institute concerning: • the incomparability of measurements of fuel performance obtained from various engine tests, • studies on the influence of various deposit control additives on the formation of harmful engine deposits during engine tests, • the influence of fuel treatments on the deposit formation processes in internal combustion engines (described qualitatively or quantitatively), • determination of the impact which various chemical compounds, serving as contaminants within the fuels, have on deposit formation in internal combustion engines and fuel injection systems, • determination of the impact that various chemical structures of the compounds within the fuels and biofuel blends have on deposit formation in internal combustion engines and fuel injection systems, • studies on the influence of bio-components contained in both petrol and diesel fuels on tendency for deposits to form in internal combustion engines, and • multidirectional studies on the impact of FAME degradation processes in biodiesel fuel blends on the formation of harmful engine deposits.

INTERNAL COMBUSTION ENGINES WITH DIRECT LIGHT FUEL INJECTION: PROBLEMS AND PROSPECTS

2016 ◽  
Vol 3 (1) ◽  
pp. 37-41
Author(s):  
Никулин ◽  
M. Nikulin ◽  
Новиков ◽  
A. Novikov
Keyword(s):  
Comparative Analysis ◽  
Internal Combustion Engines ◽  
Fuel Injection ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Gasoline Engines ◽  
Direct Light ◽  
Alternative Type ◽  
Direct Fuel Injection

In this article gasoline engines of internal combustion with direct fuel injection, their advantages and shortcomings are considered, comparative analysis of two most effective systems allowing to use gas as an alternative type of fuel.

scholarly journals Performance, Efficiency and Emissions Evaluation of Gasoline Port-Fuel Injection, Natural Gas Direct Injection and Blended Operation

2016 ◽  
Author(s):  
Michael Pamminger ◽  
Thomas Wallner ◽  
James Sevik ◽  
Riccardo Scarcelli ◽  
Carrie Hall ◽  
...  
Keyword(s):  
Natural Gas ◽  
Internal Combustion Engines ◽  
Fuel Injection ◽  
Direct Injection ◽  
Combustion Process ◽  
Internal Combustion ◽  
Intake Port ◽  
Combustion Engines ◽  
Part Load ◽  
Port Fuel Injection

The need to further reduce fuel consumption and decrease the output of emissions — in order to be within future emissions legislation — is still an ongoing effort for the development of internal combustion engines. Natural gas is a fossil fuel which is comprised mostly of methane and makes it very attractive for use in internal combustion engines because of its higher knock resistance and higher molar hydrogen-to-carbon ratio compared to gasoline. The current paper compares the combustion and emissions behavior of the test engine being operated on either a representative U.S. market gasoline or natural gas. Moreover, specific in-cylinder blend ratios with gasoline and natural gas were also investigated at part-load and wide open throttle conditions. The dilution tolerance for part-load operation was investigated by adding cooled exhaust gas recirculation. The engine used for these investigations was a single cylinder research engine for light duty application which is equipped with two separate fuel systems. Gasoline was injected into the intake port; natural gas was injected directly into the cylinder to overcome the power density loss usually connected with port fuel injection of natural gas. Injecting natural gas directly into the cylinder reduced both ignition delay and combustion duration of the combustion process compared to the injection of gasoline into the intake port. Injecting natural gas and gasoline simultaneously resulted in a higher dilution tolerance compared to operation on one of the fuels alone. Significantly higher net indicated mean effective pressure and indicated thermal efficiency were achieved when natural gas was directly injected after intake valve closing at wide open throttle, compared to an injection while the intake valves were still open. In general it was shown that the blend ratio and the start of injection need to be varied depending on load and dilution level in order to operate the engine with the highest efficiency or highest load.

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