Laser Ignition, Optics and Contamination of Optics in an I.C. Engine

2004 ◽  
Author(s):  
Josef Graf ◽  
Martin Weinrotter ◽  
Herbert Kopecek ◽  
Ernst Wintner
Keyword(s):  
Combustion Chamber ◽  
Internal Combustion Engines ◽  
Laser Energy ◽  
Direct Injection ◽  
Combustion Process ◽  
Exhaust Emission ◽  
Ignition System ◽  
Term Operation ◽  
Self Cleaning ◽  
Induced Ignition

Due to the progresses in exhaust emission after-treatment systems and in the development of new combustion processes, the S.I. engine has been booming in the past few years. But the efficiency will have to be improved in the future. Because of its thermodynamic benefits, the S.I. direct injection engine of the second generation — so called air guided system — shows the highest potential for gasoline engines to reduce fuel consumption. However, there are restrictions when using conventional spark ignition system. They concern the optimum position of ignition initialization and spark-plug wear, the latter being caused by inhomogeneous mixture distribution. The laser-induced ignition enables a flexible choice of the ignition location and a wear resistant initialization of the combustion process. The most crucial component here is the optics (the combustion-chamber window), through which the laser beam passes into the combustion chamber. In this paper, laser-induced ignition is discussed and its potential compared to a conventional ignition system is presented. In addition, several optic configurations are presented as well as tests regarding the minimum required laser energy and the optic contamination and self-cleaning effect of the optics. At the Institute of Internal Combustion Engines at the Vienna University of Technology the optic contamination and self-cleaning effect, which is crucial for a long-term operation, was tested on a two-cylinder research engine.

scholarly journals Combustion Thermodynamics of Ethanol, n-Heptane, and n-Butanol in a Rapid Compression Machine with a Dual Direct Injection (DDI) Supply System

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2729
Author(s):  
Ireneusz Pielecha ◽  
Sławomir Wierzbicki ◽  
Maciej Sidorowicz ◽  
Dariusz Pietras
Keyword(s):  
Heat Release ◽  
Combustion Chamber ◽  
Internal Combustion Engines ◽  
Direct Injection ◽  
Combustion Process ◽  
Combustion Efficiency ◽  
Injection System ◽  
Rapid Compression Machine ◽  
Process Indicators ◽  
Rapid Compression

The development of internal combustion engines involves various new solutions, one of which is the use of dual-fuel systems. The diversity of technological solutions being developed determines the efficiency of such systems, as well as the possibility of reducing the emission of carbon dioxide and exhaust components into the atmosphere. An innovative double direct injection system was used as a method for forming a mixture in the combustion chamber. The tests were carried out with the use of gasoline, ethanol, n-heptane, and n-butanol during combustion in a model test engine—the rapid compression machine (RCM). The analyzed combustion process indicators included the cylinder pressure, pressure increase rate, heat release rate, and heat release value. Optical tests of the combustion process made it possible to analyze the flame development in the observed area of the combustion chamber. The conducted research and analyses resulted in the observation that it is possible to control the excess air ratio in the direct vicinity of the spark plug just before ignition. Such possibilities occur as a result of the properties of the injected fuels, which include different amounts of air required for their stoichiometric combustion. The studies of the combustion process have shown that the combustible mixtures consisting of gasoline with another fuel are characterized by greater combustion efficiency than the mixtures composed of only a single fuel type, and that the influence of the type of fuel used is significant for the combustion process and its indicator values.

scholarly journals Determination of Combustion Process Model Parameters in Diesel Engine with Variable Compression Ratio

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Saša Milojević ◽  
Radivoje Pešić
Keyword(s):  
Diesel Engine ◽  
Compression Ratio ◽  
Process Model ◽  
Internal Combustion Engines ◽  
Combustion Process ◽  
Exhaust Emission ◽  
Model Parameters ◽  
Connecting Rod ◽  
Variable Compression Ratio ◽  
Variable Compression

Compression ratio has very important influence on fuel economy, emission, and other performances of internal combustion engines. Application of variable compression ratio in diesel engines has a number of benefits, such as limiting maximal in cylinder pressure and extended field of the optimal operating regime to the prime requirements: consumption, power, emission, noise, and multifuel capability. The manuscript presents also the patented mechanism for automatic change engine compression ratio with two-piece connecting rod. Beside experimental research, modeling of combustion process of diesel engine with direct injection has been performed. The basic problem, selection of the parameters in double Vibe function used for modeling the diesel engine combustion process, also performed for different compression ratio values. The optimal compression ratio value was defined regarding minimal fuel consumption and exhaust emission. For this purpose the test bench in the Laboratory for Engines of the Faculty of Engineering, University of Kragujevac, is brought into operation.

Effect of Engine Operating Parameters on Combustion and Emission Characteristics

1992 ◽  
Author(s):  
Jiang Lu ◽  
Ashwani K. Gupta ◽  
Eugene L. Keating
Keyword(s):  
Internal Combustion Engine ◽  
Combustion Chamber ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Combustion Process ◽  
Pressure Rise ◽  
Internal Combustion ◽  
Operating Parameters ◽  
Emission Characteristics ◽  
Pollutants Emission

Abstract Numerical simulation of flow, combustion, heat release rate and pollutants emission characteristics have been obtained using a single cylinder internal combustion engine operating with propane as the fuel. The data are compared with experimental results and show excellent agreement for peak pressure and the rate of pressure rise as a function of crank angle. The results obtained for NO and CO are also found to be in good agreement and are similar to those reported in the literature for the chosen combustion chamber geometry. The results have shown that both the combustion chamber geometry and engine operating parameters affects the flame growth within the combustion chamber which subsequently affects the pollutants emission levels. The code employed the time marching procedure and solves the governing partial differential equations of multi-component chemically reacting fluid flow by finite difference method. The numerical results provide a cost effective means of developing advanced internal combustion engine chamber geometry design that provides high efficiency and low pollution levels. It is expected that increased computational tools will be used in the future for enhancing our understanding of the detailed combustion process in internal combustion engines and all other energy conversion systems. Such detailed information is critical for the development of advanced methods for energy conservation and environmental pollution control.

scholarly journals Analysis of creation and combustion process of hydrogen-air mixtures by optical method in isochoric chamber

2017 ◽  
Vol 170 (3) ◽  
pp. 121-125
Author(s):  
Marek BRZEŻAŃSKI ◽  
Tadeusz PAPUGA ◽  
Łukasz RODAK
Keyword(s):  
Combustion Chamber ◽  
Flame Front ◽  
Dose Distribution ◽  
Optical Method ◽  
Direct Injection ◽  
Combustion Process ◽  
Variable Composition ◽  
Mixture Formation ◽  
Before And After

The article considers the analysis of combustion process of hydrogen-air mixture of variable composition. Direct injection of hydrogen into the isochoric combustion chamber was applied and the mixture formation took place during the combustion process. The influence of the dose distribution of the fuel supplied before and after ignition on the formation of the flame front and the course of the pressure in the isochoric combustion chamber was discussed. The filming process and registration of pressure in the isochoric chamber during research of combustion process was applied.

A comprehensive evaluation of water injection in the diesel engine

2021 ◽  
pp. 146808742110442
Author(s):  
Sebastian Welscher ◽  
Mohammad Hossein Moradi ◽  
Antonino Vacca ◽  
Peter Bloch ◽  
Michael Grill ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Internal Combustion Engines ◽  
Comprehensive Evaluation ◽  
Combustion Engine ◽  
Water Injection ◽  
Combustion Process ◽  
Internal Combustion ◽  
Exhaust Emission ◽  
Pressure Trace ◽  
High Level

Due to increasing climate awareness and the introduction of much stricter exhaust emission legislation the internal combustion engine technology faces major challenges. Although the development and state of technology of internal combustion engines generally reached a very high level over the last years those need to be improved even more. Combining water injection with a diesel engine, therefore, seems to be the next logical step in developing a highly efficient drive train for future mobility. To investigate these potentials, a comprehensive evaluation of water injection on the diesel engine was carried out. This study covers >560 individual operating points on the test bench. The tests were carried out on a single-cylinder derived from a Euro 6d four-cylinder passenger car with the port water injection. Furthermore, a detailed pressure trace analysis (PTA) was performed to evaluate various aspects regarding combustion, emission, etc. The results show no significant effects of water injection on the combustion process, but great potential for NOx reduction. It has been shown that with the use of water injection at water-to-fuel rates of 25%, 50%, and 100%, NOx reduction without deterioration of soot levels can be achieved in 62%, 40%, and 20% of the experiments, respectively. Furthermore, water injection in combination with EGR offers additional reduction in NOx emissions.

Experimental and Theoretical Optimization of Combustion Chamber and Fuel Distribution for the Low Emission Direct-Injection Diesel Engine

2002 ◽  
Vol 125 (1) ◽  
pp. 351-357 ◽  
Author(s):  
Y. Kidoguchi ◽  
M. Sanda ◽  
K. Miwa
Keyword(s):  
Diesel Engine ◽  
Combustion Chamber ◽  
Direct Injection ◽  
Combustion Process ◽  
Mixture Distribution ◽  
Initial Mixture ◽  
Injection Timing ◽  
Particulate Emissions ◽  
Particulate Emission ◽  
Direct Injection Diesel Engine

Effects of combustion chamber geometry and initial mixture distribution on the combustion process were investigated in a direct-injection diesel engine. In the engine experiment, a high squish combustion chamber with a squish lip could reduce both NOx and particulate emissions with retarded injection timing. According to the results of CFD computation and phenomenological modeling, the high squish combustion chamber with a central pip is effective to keep the combusting mixture under the squish lip until the end of combustion and the combustion region forms rich and highly turbulent atmosphere. This kind of mixture distribution tends to reduce initial burning, resulting in restraint of NOx emission while keeping low particulate emission.

Shaping the Combustion Chamber of a Piston Engine with Direct Injection of Gasoline

2019 ◽  
pp. 67-76
Author(s):  
R.Z. Kavtaradze ◽  
A.A. Kasko ◽  
A.A. Zelentsov
Keyword(s):  
Combustion Chamber ◽  
Direct Injection ◽  
Combustion Process ◽  
Three Dimensional ◽  
Numerical Control ◽  
Engine Operation ◽  
Model Fuel ◽  
Nonstationary Equations ◽  
Current Lines ◽  
Control Volumes

The object of the study was a six-cylinder in-line engine for land transport system with direct gasoline supply and forced ignition. The problem of shaping the combustion chamber is solved using the numerical control volumes method in a three-dimensional formulation. Nonstationary equations of energy, motion, diffusion and continuity in the Reynolds form, supplemented by the k-ζ-f model of turbulence, are used as a basis for modelling the engine operation. To model fuel combustion, an extended coherent flame model (ECFM) was used. Calculations were performed using the AVL FIRE software. The processes of mixture formation were optimized by considering the current lines and velocity fields of a moving charge, taking into account the geometry of the combustion chamber and intake and exhaust ports. As a result, the efficiency of the engine increased and the combustion process became more stable in the part load modes employing different fuel supply laws.

Qualitative Estimation Criterion of Direct Injection Diesel Engines Performance Prediction for Stationary and Industrial Applications

2014 ◽  
Vol 659 ◽  
pp. 205-210
Author(s):  
Vladimir Mărdărescu ◽  
Nicolae Ispas ◽  
Mircea Nastasoiu
Keyword(s):  
Diesel Engines ◽  
Internal Combustion Engines ◽  
Direct Injection ◽  
Combustion Process ◽  
Internal Combustion ◽  
Industrial Applications ◽  
Nozzle Geometry ◽  
Technical Solution ◽  
Test Bed ◽  
Injection Pump

Our approach is to define as accurately as possible, the opportunities of forecasting the environmental and energetically qualities of direct injection Diesel engines for stationary and industrial applications. This research requires the validation of new energy solutions or injection process. Knowing that test bench research of internal combustion engines is a task that requires highly qualified personnel and very expensive equipment for investigate the combustion process, a research program to define the best technical solution involves significant costs. The energetically solution of an internal combustion engine, similar to those examined in this paper, is defined by the following guidelines and parameters: - Control of mixture formation; - Compression ratio; - Average swirl intake number channel; - Geometry of the intake and exhaust cams; - Diagram of distribution; - Drive cam type injection pump; - Geometry of the combustion chamber; - Type and nozzle geometry (sack configuration and l / d ratio ); - Needle stroke; - The diameter and length of the injection pipe; - Amount of injector opening pressure (for hydraulic injectors); - Type of delivery valve; - Time of injection. Based on experience gained during the test at the test bed, we proposed a criterion for assessing qualitative performance of Diesel class discussed above. This criterion refers to environmental and energetically performance, as a prediction of performance at nominal regime, after shorten tests with cold engine.

scholarly journals Analisa posisi derajat tonjolan magnet (trigger magnet) pada konsumsi bahan bakar

2018 ◽  
Vol 1 (1) ◽  
pp. 42
Author(s):  
Fatkur Rhohman ◽  
Susdi Subandriyo ◽  
Hesti Istiqlaliyah
Keyword(s):  
Combustion Chamber ◽  
Electric Current ◽  
High Voltage ◽  
Rotation Rate ◽  
Combustion Process ◽  
Engine Performance ◽  
Ignition System ◽  
Spark Plug ◽  
Significant Difference ◽  
Independent Variable

In automotive, many various modifications are made to improve engine performance. One that is done is to maximize the combustion that occurs in the combustion chamber. By maximizing the ignition system in the combustion process, it is expected to enlarge sparks from spark plugs. One of the components affecting the combustion process is Magnet, serves to generate electricity that will become a high voltage electric current and allow the occurrence of spark jumps on the spark plug. In this study, the independent variable is the modified tregger magnet which is reversed 0.50, to 9.50 and 90. in general there is no significant difference. Fcount value for result on magnetic trigger type = 3.00 <F (0.05; 2.24) = 3.40 (rejected H0) means reversing the 90 and 9.50 magnetic triggers does not significantly influence. In addition, Fcount for 6000, 7000, 8000 rpm engine yield = 1.00 <F (0.05; 2.24) = 3.40 (Rejected H0) means the engine's rotation rate has no significant effect. So there is no effect of fuel consumption on the modified magnetic trigger, nor at rpm 6000, rpm 7000 and rpm 8000.

scholarly journals New engine method for biodiesel cetane number testing

2008 ◽  
Vol 12 (1) ◽  
pp. 125-138 ◽  
Author(s):  
Radivoje Pesic ◽  
Aleksandar Davinic ◽  
Stevan Veinovic
Keyword(s):  
Internal Combustion Engines ◽  
Fossil Fuels ◽  
Direct Injection ◽  
Cetane Number ◽  
Combustion Process ◽  
Laboratory Equipment ◽  
Auto Ignition ◽  
Working Parameters ◽  
Biodiesel Fuels ◽  
Engine Method

Substitution of fossil fuels with fuels that come from part renewable sources has been a subject of many studies and researches in the past decade. Considering the higher cost and limits of production resources, a special attention is focused on raising the energy efficiency of biofuel usage, mainly through optimization of the combustion process. Consequently, in biofuel applications, there is a need for determination of auto-ignition quality expressed by cetane number as a dominant characteristic that influences combustion parameters. The fact that the method for cetane number determination is comparative in nature has led us to try to develop substitute engine method for cetane number determination, by the use of the available laboratory equipment and serial, mono-cylinder engine with direct injection, DMB LDA 450. Description of the method, results of optimization of engine?s working parameters for conduction of the test and method?s Accuracy estimation are given in the paper. The paper also presents the results of domestic biodiesel fuels cetane number testing with the application of described engine method, developed at the Laboratory for internal combustion engines and fuels and lubricants of the Faculty of Mechanical Engineering from Kragujevac, Serbia.

Sign in / Sign up

Export Citation Format

Share Document