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Pulse Detonation Engine has been a point of interest in the propulsion industry for some time and the interest has been rising due to its better output and results. But any system can perform its task efficiently based on the efficiency of its control system. In this paper we have presented a comparative study between multiple control systems- one based on Bluetooth technology, the other based on infrared sensor technology and one based on wired electrical system. For the wireless system, the signal received from either of the media is passed to the various sensors and systems connected through an Arduino board that further controls the solenoid valves and ignition system. Primarily, a control system circuit is developed using Arduino board and different sensors to connect the fuel supply and ignition system. In the next stage, Bluetooth sensors are connected using an android app and then an infrared sensor based system is integrated with the Arduino to control the engine and the performance of the two systems are compared. Whereas for wired system, every sub system is controlled through optical wires including the solenoid valves, the injection system and the sensors.

The medium-voltage components in the ignition installations for gasoline engines contain electroinsulating materials that lose their properties over time. The purpose of this paper is to measure and analyze the insulation resistance, dielectric absorption ratio and polarization index of the insulation of materials (three types of materials) used for medium-voltage distributors, for several operating periods, in automotive ignition installations. Experiments were conducted with old (operation tens of thousands of km, some with surfaces that have been cleaned) and new medium-voltage distributors, and a megohmmeter was used to measure, over time, the insulation resistance between the central terminal and the output terminals at different test voltages. The insulation resistance of the distributors depends on the use: in the old ones, they have values of tens of GΩ (e.g., up to 100 GΩ) and, in the new ones, of the order of TΩ (e.g., 4–7 TΩ). The more distributors are used, for the same distributor, there are greater differences between the measurements made between terminals and the average values (87% for used distributors, respectively, 2% for new ones). For new or less used distributors, higher values were obtained for the dielectric absorption ratio (1.26–1.27; for used ones, 0.91–0.95) and polarization index (1.15–1.25; for used ones, 0.96–1.15). The results show the importance of the volume insulation resistance of the electroinsulating material compared to the surface resistance and the insignificant improvement when cleaning the internal and external surfaces of the medium-voltage distributors. [ABSTRACT FROM AUTHOR]

Pulse Detonation Engine has been a point of interest in the propulsion industry for some time and the interest has been rising due to its better output and results. But any system can perform its task efficiently based on the efficiency of its control system. In this paper we have presented a comparative study between multiple control systems- one based on Bluetooth technology, the other based on infrared sensor technology and one based on wired electrical system. For the wireless system, the signal received from either of the media is passed to the various sensors and systems connected through an Arduino board that further controls the solenoid valves and ignition system. Primarily, a control system circuit is developed using Arduino board and different sensors to connect the fuel supply and ignition system. In the next stage, Bluetooth sensors are connected using an android app and then an infrared sensor based system is integrated with the Arduino to control the engine and the performance of the two systems are compared. Whereas for wired system, every sub system is controlled through optical wires including the solenoid valves, the injection system and the sensors. [ABSTRACT FROM AUTHOR]

The paper presents the results of the experimental research on the combustion process inside the cylinder of a large piston radial aircraft engine with dual spark plug ignition. The tests were carried out on the ASz-62IR-16X radial engine equipped with a double, electronically controlled ignition system with two spark plugs in each cylinder. The constant engine speed tests allowed for comparing the combustion processes with ignition carried out with different ignition advance angle offset between both spark plugs. In the test, the ignition advance angle for one spark plug was changed while leaving the ignition advance angle for the other spark plug. The tests performed for two engine operating points were to change the angle of the front spark plug and the rear spark plug. The analyses were based on the recorded pressure signal from one of the engine cylinders. It has been shown that the ignition advance angle offset significantly affects the combustion process. The obtained results indicate the leading role of the rear spark plug in initiating the combustion process. When ignition is carried out with a steady rear spark plug advance angle, the combustion process practically does not change when the ignition advance angle of the front spark plug changes. However, changing the rear spark plug advance angle at a constant front spark plug ignition advance angle significantly changes the combustion process. [ABSTRACT FROM AUTHOR]

The medium-voltage components in the ignition installations for gasoline engines contain electroinsulating materials that lose their properties over time. The purpose of this paper is to measure and analyze the insulation resistance, dielectric absorption ratio and polarization index of the insulation of materials (three types of materials) used for medium-voltage distributors, for several operating periods, in automotive ignition installations. Experiments were conducted with old (operation tens of thousands of km, some with surfaces that have been cleaned) and new medium-voltage distributors, and a megohmmeter was used to measure, over time, the insulation resistance between the central terminal and the output terminals at different test voltages. The insulation resistance of the distributors depends on the use: in the old ones, they have values of tens of GΩ (e.g., up to 100 GΩ) and, in the new ones, of the order of TΩ (e.g., 4–7 TΩ). The more distributors are used, for the same distributor, there are greater differences between the measurements made between terminals and the average values (87% for used distributors, respectively, 2% for new ones). For new or less used distributors, higher values were obtained for the dielectric absorption ratio (1.26–1.27; for used ones, 0.91–0.95) and polarization index (1.15–1.25; for used ones, 0.96–1.15). The results show the importance of the volume insulation resistance of the electroinsulating material compared to the surface resistance and the insignificant improvement when cleaning the internal and external surfaces of the medium-voltage distributors.

The main objective of the research is to assess the influence of the spark plug electrodes geometry on the structure of the electric arc. This issue is increasingly important in modern gas-fueled engines with lean and stratified air-gas mixtures. To explain the influence of electrode geometry on selected spark discharge indicators, optical tests were conducted, and the parameters of the test history, together with the movies of the discharging process, were recorded and analyzed. The tests were carried out comparatively for two types of spark plugs on the test stand: conventional spark plug and spark plug with a flat ground electrode. It has been found that using flat plug electrodes allows a larger spark area covered by the electric arc without losing the intensity of radiation. More, using an unconventional spark plug results in a shorter discharge time relative to the conventional spark plug, while the geometry of the conventional spark plug allows for maintaining a stable electric arc with a minimum tendency for creeping. [ABSTRACT FROM AUTHOR]

The article discusses the key role of the use of automation in the stands, as well as the ignition system of the stand of low-thrust engines and the features of its operation as part of the stand. The ignition system scheme was developed, assembled and worked out, on the basis of which the ignition of the components of the propulsion system mixture will be carried out. The ignition system was tested by directly connecting the power supply to the circuit, which during the tests showed its suitability for use due to the long and continuous operation of the system. The power was turned on by controlling relay switches based on the Arduino MEGA 2560. Also, an algorithm was developed for the operation of the automation system for switching on, off and checking the entire system before testing the propulsion system on the stand of low-thrust engines to ensure automation and safety of using the stand. This algorithm includes control of two channels of the oxidizer and fuel pipeline, emergency power off, opening and closing of cut-off valves, taking readings and checking pressure gauges and flow meters, as well as shutting down the system after testing low-thrust engines using an Arduino MEGA controller.

It is known that the proportion of failures of the elements of the power supply system of automobile piston engines reaches 45% of all its failures, including 9% of cases are failures of the elements of the ignition system. An analysis of this statistics shows that spark plugs are most susceptible to wear, overheating and significant loading. The range of resource parameters of spark plugs offered by manufacturers within 10-60 thousand km aggravates the situation of timely replacement. It was revealed that the period for replacing spark plugs can be adjusted, since their guaranteed resource sometimes does not correspond to the declared one. It has been determined that the means used for diagnosing the ignition system (in the classic version: a motor-tester, a gas analyzer) do not allow to accentuate the load on a separate element and bring it to an extreme operating mode, in which hidden failures appear. The sensitivity and reliability of existing methods are at a low level, because Many factors influence the shape of the oscillogram, including interference in the measuring circuit and measurement errors, the need for frequent calibration of the measuring channels, which introduces a significant error in the diagnostic process. The purpose of the research is to increase the reliability of diagnosing the elements of the ignition system of automobile engines based on the analysis of toxicity parameters during selective sampling of exhaust gases in test modes. A method for troubleshooting and assessing the technical condition of the elements of the ignition system in test modes with selective sampling of exhaust gases is proposed, for the implementation of which a software and hardware complex for test diagnostics has been developed. On the basis of the developed methods, a methodology for the comprehensive determination of the technical condition of spark plugs in the engines of VAZ and GAZ vehicles was created based on the results of the analysis of the composition of exhaust gases on comparative nomograms. Scientific novelty: a mathematical model of the change in the secondary voltage depending on the spark interelectrode gap of the spark plug has been developed; the relationship between the breakdown voltage in the interelectrode gap of the spark plug and the air density in the chamber of the test device is established, where the most significant factor is the discrepancy between the interelectrode gap of the spark plug to its nominal value: the dependence of the parameters of the composition and content of harmful substances in the exhaust gases on the technical condition of the elements of the ignition system in individual engine cylinders. The practical significance of the work lies in the possibility of continuous monitoring of the elements of the ignition system by the test method, in particular the spark plugs of the ignition system, taking into account the individual contribution of each spark plug to the exhaust process and the content of toxicity parameters in the exhaust gases. Further research on this topic should be extended to other brands of cars, as well as gas engine installations with elements of automating the diagnostic process.

Degradation of the ignition system can result in startup failure in an aircraft's auxiliary power unit. In this paper, a novel acoustics-based solution that can enable condition monitoring of an APU ignition system was proposed. In order to support the implementation of this research study, the experimental data set from Cranfield University's Boeing 737-400 aircraft was utilized. The overall execution of the approach comprised background noise suppression, estimation of the spark repetition frequency and its fluctuation, spark event segmentation, and feature extraction, in order to monitor the state of the ignition system. The methodology successfully demonstrated the usefulness of the approach in terms of detecting inconsistencies in the behavior of the ignition exciter, as well as detecting trends in the degradation of spark acoustic characteristics. The identified features proved to be robust against non-stationary background noise, and were also found to be independent of the acoustic path between the igniter and microphone locations, qualifying an acoustics-based approach to be practically viable. [ABSTRACT FROM AUTHOR]

The current work is devoted to studying combustion initiation inside the methane-oxygen torch igniter for a hybrid rocket motor. The ignition system can generate a wide range of power and oxidizer-to-fuel ratios. It has a self-cooled vortex combustion chamber with one fuel jet injector and one circumferential vortex oxidizer injector. The system adjusts the mass flow rates of the propellants through the control valves and organizes cooling of the wall and flame stabilization. Experimental analysis of the ignition limits was investigated on the laboratory test bench. The propellants' pressure and mass-flow rates, combustion temperature, ignition delay, and spark frequency were controlled during the tests. The authors executed a series of tests with different propellants' mass flow rates. As a result, the region of stable ignition was found as well as the regions of ignition failure or unreliable ignition. A previously validated numerical model was used to analyze the flow in the reliable ignition region and the ignition failures region. Several numerical simulations of the transient three-dimensional chemically reacting flow were implemented. Consequently, the ignition delay and the thermal impact on the combustion chamber wall were determined numerically. Results of the simulations were compared with theoretical and experimental data showing good correspondence. [ABSTRACT FROM AUTHOR]

Paper presents diagnostic analysis of automotive ignition system for various working and adverse conditions in laboratory. Description and importance of basic diagnostics of automotive ignition system are examined in the first part of the paper. In the second the focus is placed on the basic principles and solution of the spark plug model. The test laboratory device is proposed in the following and the specialized measurements were executed by the proposed measurement system. The faults were simulated by application of oil and gasoline between the electrodes and failing by the driver to make the ignition contact on the spark plug.

Abstract The ignition process initiates the combustion in spark-ignition engines. Therefore, understanding the ignition process is an important aspect in developing more efficient combustion engines. In this thesis, the vibrational temperature of an ignition spark in air under atmospheric pressure and room temperature is observed in spatial and temporal resolution. The temperature is determined by comparing simulated spectra with the measured spectra of the second positive system of N2 between 360 and 381 nm. Changing the dwell time had no significant effect on the vibrational temperature of the three spark phases. In the breakdown the vibrational temperature is about 3300 K. The vibrational temperature of the following arc discharge is in the range of 3750 K to 4350 K. The glow discharge is divided into the negative glow and the positive column. Both show similar vibration temperatures in the range of 3500 K to 3900 K.

This paper is concerned with a Coupled Reaction-diffusion system defined in a ball with homogeneous Dirichlet boundary conditions. Firstly, we studied the blowup set showing that, under some conditions, the blow-up in this problem occurs only at a single point. Secondly, under some restricted assumptions on the reaction terms, we established the upper (lower) blow-up rate estimates. Finally, we considered the Ignition system in general dimensional space as an application to our results. [ABSTRACT FROM AUTHOR]

Degradation of the ignition system can result in startup failure in an aircraft’s auxiliary power unit. In this paper, a novel acoustics-based solution that can enable condition monitoring of an APU ignition system was proposed. In order to support the implementation of this research study, the experimental data set from Cranfield University’s Boeing 737-400 aircraft was utilized. The overall execution of the approach comprised background noise suppression, estimation of the spark repetition frequency and its fluctuation, spark event segmentation, and feature extraction, in order to monitor the state of the ignition system. The methodology successfully demonstrated the usefulness of the approach in terms of detecting inconsistencies in the behavior of the ignition exciter, as well as detecting trends in the degradation of spark acoustic characteristics. The identified features proved to be robust against non-stationary background noise, and were also found to be independent of the acoustic path between the igniter and microphone locations, qualifying an acoustics-based approach to be practically viable.

To meet the future requirements of fuel economy and exhaust emissions, high-efficiency gasoline engines tend to employ diluted combustion concepts along with intensified charge motion and stratified mixtures. Securing the ignition of such mixtures over the full engine operation range is challenging, because of the lowered mixture reactivity and increased discrepancy of stoichiometry. In recent years, increasing research efforts have been spending on innovations of ignition technologies to tackle the challenges. In this paper, the directions of ignition improvement are highlighted based on the fundamental understanding of the ignition mechanisms. The working principles of the primary types of advanced ignition systems are introduced; and relevant engine and combustion vessel test results are reviewed. The ignition systems are categorized as: (1) high-energy spark ignition, (2) pulsed nanosecond discharge ignition, (3) radio-frequency plasma ignition, (4) laser-induced plasma ignition, and (5) pre-chamber ignition. The advanced ignition systems are commented, regarding the ignition effectiveness and the implementation challenges, according to the literatures and the extensive empirical work at the authors' laboratory. [ABSTRACT FROM AUTHOR]

Aircraft piston engines are built with compromise on performance and safety. The desire to achieve the highest power-to-weight ratio leads to the search for solutions that optimize the combustion process. On the other hand, the need for maximum reliability leads to the simplification of the design at the costs of performance. An example of such a compromise is the ignition system of the ASz-62IR engine. In this engine there is a double magneto ignition system with a fixed ignition advance angle. As part of the modernisation of this engine, an electronically controlled dual ignition system was developed, which allows for optimum control of the ignition advance angle in terms of power. This article discusses the results of bench tests of the ASZ-62IR-16X engine with fixed ignition timing and variable timing control. Functional parameters and toxicity of exhaust gases were analyzed.

Current and further developing CO2- and emission regulations worldwide and the competition to full electric mobility deliver a chal-lenge for internal combustion engines in general. A state of the art solution is the use of natural gas mainly contending methane to reduce CO2 significantly and to offer lowest emission levels. The EU-funded project GasOn developed engine concepts to fully exploit the advantages of CNG. This article describes the development of an innovative, monovalent engine dedicated to Compressed Natural Gas (CNG) and characterised by the lean burn concept and the innovative pre-chamber combustion.

The current work is devoted to studying combustion initiation inside the methane-oxygen torch igniter for a hybrid rocket motor. The ignition system can generate a wide range of power and oxidizer-to-fuel ratios. It has a self-cooled vortex combustion chamber with one fuel jet injector and one circumferential vortex oxidizer injector. The system adjusts the mass flow rates of the propellants through the control valves and organizes cooling of the wall and flame stabilization. Experimental analysis of the ignition limits was investigated on the laboratory test bench. The propellants’ pressure and mass-flow rates, combustion temperature, ignition delay, and spark frequency were controlled during the tests. The authors executed a series of tests with different propellants’ mass flow rates. As a result, the region of stable ignition was found as well as the regions of ignition failure or unreliable ignition. A previously validated numerical model was used to analyze the flow in the reliable ignition region and the ignition failures region. Several numerical simulations of the transient three-dimensional chemically reacting flow were implemented. Consequently, the ignition delay and the thermal impact on the combustion chamber wall were determined numerically. Results of the simulations were compared with theoretical and experimental data showing good correspondence.

This paper discusses the research and analysis of the dynamics of high-voltage generating systems. The test subject is an ignition system modelled by a set of two induction coils with an open ferromagnetic core that constitutes an ignition coil. The essence of the tests involved the application of magnetic coupling of the fractional order that enabled taking into account the non-idealities of the coils and the connector that implements the ignition point. The paper contains the results of a theoretical analysis, supported by digital simulations. The conducted experiments confirm the purposefulness of the conducted analyses and the possibility of modeling real objects based on circuits with fractional-order elements.

The paper presents the results of analytical and experimental studies concerning the influence of different kinds of fuel additives on the quality of the spark discharge for different configurations of the ignition system. The wear of the spark plug electrode and the value of spark discharge were determined for various impurities and configurations of the air-fuel mixture.

To meet the conditions of diesel ignition, this paper presents several structural improvements of a small missile turbojet engine for diesel fuel. The engine starts motor-assisted, and its fuel is ignited by silicon nitride ceramic ignitor. Theoretical analysis is performed by establishing a mathematical model of the combustion model and combustion conditions. The feasibility of diesel used as a small turbojet fuel is analyzed by using numerical simulation software. Research is carried out based on the following points: the improvement of combustion chamber and evaporator, selection of ignitor position and sustainability of fire. This paper proposed the method of linking the engine-assisting startup system and selected the right type of ignitor, and on the advanced experimental platform several groups ignition tests were carried out.

Paper presents diagnostic analysis of automotive ignition system for various working and adverse conditions in laboratory. Description and importance of basic diagnostics of automotive ignition system are examined in the first part of the paper. In the second the focus is placed on the basic principles and solution of the spark plug model. The test laboratory device is proposed in the following and the specialized measurements were executed by the proposed measurement system. The faults were simulated by application of oil and gasoline between the electrodes and failing by the driver to make the ignition contact on the spark plug. [ABSTRACT FROM AUTHOR]

The paper analyses the possibilities of treating the ignition cable in the internal combustion engine as a distributed parameter system. It presents the experimental verification of computer simulations of signal propagation generated by ignition systems in the ignition cables, modelled by the distributed parameter system. The tests conducted to determine the wave parameters of ignition cables, as well as the results of numerical simulations and their experimental verifications, are presented. It is concluded that the modelling of the ignition cable by means of a long line gives positive results that can be used for the design of a spark plug with impedance equal to wave impedance of the ignition cable.