Removing carbon deposits from parts of the combustion chamber of diesel engines

Author(s):  

The Leader4M apparatus for removing carbon deposition with the help of hydrogenair mixture in internal combustion engines was developed. The efficiency of this apparatus when cleaning the engine parts from carbonand coke deposition was proved. Power indicators of diesel engines of BMW X1 2.0 td and Land Rover Discovery 3.0 td were measured before and after cleaning the combustion chamber parts of these engines using the Leader4M installation. After cleaning the parts of these engines from carbon deposits using the Leader4M unit, the maximum power of the engines increased by 2.0–2.1 %, and the maximum torque of these engines increased by 0.2–1.8 %. Keywords internal combustion engines; diesel engine; diesel fuel; carbon formation; hydrogenair mixture

Author(s):  
Randy P. Hessel ◽  
Ettore Musu ◽  
Salvador M. Aceves ◽  
Daniel L. Flowers

A computational mesh is required when performing CFD-combustion modeling of internal combustion engines. For combustion chambers with moving pistons and valves, like those in typical cars and trucks, the combustion chamber shape changes continually in response to piston and valve motion. The combustion chamber mesh must then also change at each time step to reflect that change in geometry. The method of changing the mesh from one computational time step to the next is called rezoning. This paper introduces a new method of mesh rezoning for the KIVA3V CFD-combustion program. The standard KIVA3V code from Los Alamos National Laboratory comes with standard rezoners that very nicely handle mesh motion for combustion chambers whose mesh does not include valves and for those with flat heads employing vertical valves. For pent-roof and wedge-roof designs KIVA3V offers three rezoners to choose from, the choice depending on how similar a combustion chamber is to the sample combustion chambers that come with KIVA3V. Often, the rezoners must be modified for meshes of new combustion chamber geometries to allow the mesh to successfully capture change in geometry during the full engine cycle without errors. There is no formal way to approach these modifications; typically this requires a long trial and error process to get a mesh to work for a full engine cycle. The benefit of the new rezoner is that it replaces the three existing rezoners for canted valve configurations with a single rezoner and has much greater stability, so the need for ad hoc modifications of the rezoner is greatly reduced. This paper explains how the new rezoner works and gives examples of its use.


Author(s):  
T. Shudo ◽  
H. Oka

Hydrogen is a clean alternative to fossil fuels for internal combustion engines and can be easily used in spark-ignition engines. However, the characteristics of the engines fueled with hydrogen are largely different from those with conventional hydrocarbon fuels. A higher burning velocity and a shorter quenching distance for hydrogen as compared with hydrocarbons bring a higher degree of constant volume and a larger heat transfer from the burning gas to the combustion chamber wall of the engines. Because of the large heat loss, the thermal efficiency of an engine fueled with hydrogen is sometimes lower than that with hydrocarbons. Therefore, the analysis and the reduction of the heat loss are crucial for the efficient utilization of hydrogen in internal combustion engines. The empirical correlations to describe the total heat transferred from the burning gas to the combustion chamber walls are often used to calculate the heat loss in internal combustion engines. However, the previous research by one of the authors has shown that the widely used heat transfer correlations cannot be properly applied to the hydrogen combustion even with adjusting the constants in them. For this background, this research analyzes the relationship between characteristics of thermophysical properties of working substance and heat transfer to the wall in a spark-ignition engine fueled with hydrogen.


2020 ◽  
Vol 5 (4(73)) ◽  
pp. 35-41
Author(s):  
A.G. Taranin

The present publication illuminate the tasks as follows: Electronic indicator proper usage at four–stroke internal combustion engines (diesel engines) indication; Indication results & diagram proper transfer to PC; indicator diagram top dead center TDC correction and engine performance data output values such as PMI–mean indicated pressure, PME–mean effective pressure, NIND–indicated power and NEFF–effective power proper calculations for each cylinder and engine total.


CrystEngComm ◽  
2019 ◽  
Vol 21 (30) ◽  
pp. 4427-4436
Author(s):  
X. Liu ◽  
C. L. Bull ◽  
A. K. Kleppe ◽  
P. J. Dowding ◽  
K. Lewtas ◽  
...  

The widespread use of biodiesel as a renewable fuel offers many potential advantages, but at the same time presents challenges for modern internal combustion engines, particularly for those that involve high-pressure injection of fuel into the combustion chamber.


2021 ◽  
Author(s):  
Sicong Wu ◽  
Saumil S. Patel ◽  
Muhsin M. Ameen

Abstract Modern internal combustion engines (ICE) operate at the ragged edge of stable operation characterized by high cycle-to-cycle variations (CCV). A key scientific challenge for ICE is the understanding, modeling, and control of CCV in engine performance, which can contribute to partial burns, misfire, and knock. The objective of the current study is to use high-fidelity numerical simulations to improve the understanding of the causes of CCV. Nek5000, a leading high-order spectral element, open source code, is used to simulate the turbulent flow in the engine combustion chamber. Multi-cycle, wall-resolved large-eddy simulations (LES) are performed for the General Motors (GM), Transparent Combustion Chamber (TCC-III) optical engine under motored operating conditions. The mean and root-mean-square (r.m.s.) of the in-cylinder flow fields at various piston positions are validated using PIV measurements during the intake and compression strokes. The large-scale flow structures, including the swirl and tumble flow patterns, are analyzed in detail and the causes for cyclic variabilities in these flow features are explained. The energy distribution across the different scales of the flow are quantified using one-dimensional energy spectra, and the effect of the tumble breakdown process on the energy distribution is examined. The insights from the current study can help us develop improved engine designs with reduced cyclic variabilities in the in-cylinder flow leading to enhanced engine performance.


Author(s):  
Serhii Kovalov

The expediency and advantages of using gas motor fuels, in particular, liquefied petroleum gas with respect to traditional liquid motor fuels, are shown. Technical solutions for the use of liquefied petroleum gas by diesel engines are presented and analysed. The expediency and advantages of converting diesel engines to gas spark ignition internal combustion engines with respect to conversion to gas diesel engines. Developed by the Ukrainian synthesis technology Avenir Gaz has for converting diesel engines to gas internal combustion engines with spark ignition. According to the synthesis technology of Avenir Gaz, re-equipment of diesel engines of vehicles is carried out on the basis of the universal electronic control system for gas internal combustion engines, which is based on the multifunctional electronic microprocessor control unit Avenir Gaz 37. The developed electronic microprocessor control system for gas internal combustion engines with forced ignition has a modular structure and consists of two main and a number of additional subsystems. A schematic diagram of a universal electronic control system of a gas internal combustion engine with spark ignition for operation on liquefied petroleum gas is presented. The principle of operation of the main subsystems, which include the subsystem of power management and injection of liquefied petroleum gas by gas electromagnetic injectors into the intake manifold of a gas engine, and the principle of operation of the control subsystem of the ignition with two-spark ignition coils are described. A multifunctional electronic control unit Avenir Gaz 37 has been designed and manufactured. Non-motorized tests of the electronic control unit confirmed its performance. Based on the synthesis technology of Avenir Gaz using the universal electronic control system for gas internal combustion engines with the Avenir Gaz 37 ECU, the D-240 diesel engine was converted into a gas spark ignition internal combustion engine of the D-240-LPG model. Keywords: gas internal combustion engine with forced ignition, liquefied petroleum gas (LPG), electronic microprocessor control system for gas internal combustion engines, vehicles operating on LPG.


Author(s):  
Bijan Yadollahi ◽  
Masoud Boroomand

Due to the vast resources of natural gas (NG), it has emerged as an alternative fuel for SI internal combustion engines in recent years. The need to have better fuel economy and less emission especially that of greenhouse gases has resulted in development of NG fueled engines. Direct injection of natural gas into the cylinder of SI internal combustion engines has shown great potential for improvement of performance and reduction of engine emissions especially CO2 and PM. Direct injection of NG into the cylinder of SI engines is rather new thus the flow field phenomena and suitable configuration of injector and combustion chamber geometry has not been investigated completely. In this study a numerical model has been developed in AVL FIRE software to perform investigation of direct natural gas injection into the cylinder of spark ignition internal combustion engines. In this regard, two main parts have been taken into consideration aiming to convert an MPFI gasoline engine to direct injection NG engine. In the first part of study multidimensional numerical simulation of transient injection process, mixing and flow field have been performed via different validation cases in order to assure the numerical model validity of results. Adaption of such a modeling was found to be a challenging task because of required computational effort and numerical instabilities. In all cases present results were found to have excellent agreement with experimental and numerical results from literature. In the second part, using the moving mesh capability, the validated model has been applied to methane injection into the cylinder of a direct injection engine. Five different piston head shapes have been taken into consideration in investigations. An inwardly opening multi-hole injector has been adapted to all cases. The injector location has been set to be centrally mounted. The effects of combustion chamber geometry have been studied on mixing of air-fuel inside cylinder via quantitative and qualitative representation of results. Based on the results, suitable geometrical configuration for a NG DI engine has been discussed.


2020 ◽  
Vol 5 (4(73)) ◽  
pp. 42-49
Author(s):  
A.G. Taranin

The present publication illuminate the tasks as follows: Electronic indicator proper usage at four–stroke internal combustion engines (diesel engines) indication; Indication results & diagram proper transfer to PC; indicator diagram top dead center TDC correction and engine performance data output values such as PMI–mean indicated pressure, PME–mean effective pressure, NIND–indicated power and NEFF–effective power proper calculations for each cylinder and engine total.


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