Assessment of the reliability of ionization current measurement in estimating peak pressure angle in a spark ignition engine

2021 ◽  
pp. 146808742110399
Author(s):  
Veniero Giglio ◽  
Livia Della Ragione ◽  
Alessandro di Gaeta ◽  
Natale Rispoli
Keyword(s):  
Peak Pressure ◽  
Angular Position ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Mean Values ◽  
Pressure Angle ◽  
Ionization Current ◽  
Significant Difference ◽  
Second Peak

Ionization current measured at the spark plug during combustion in spark ignition engines has often been proposed to determine the crank-angle at combustion pressure peak, namely the peak pressure angle, for the purpose of regulating spark timing to attain maximum brake torque (MBT). The proposal is based on the assumption that agreement exists between peak pressure angle and the angular position of the ionization current second peak, although no one has ever proved it by an appropriate statistical analysis. The aim of this work, for the first time and by rigorous statistical methods, is to prove the agreement between Peak Pressure Angle and Ionization Current Second Peak Angle (ICSPA), without which a MBT control via ICSPA would be ineffective. Our experimental database consisted of about 9000 pairs of Peak Pressure Angle and Ionization Current Second Peak Angle values corresponding to 90 different operating conditions of a spark ignition engine. A two-sample comparison was first carried out between mean values of Peak Pressure Angle and Ionization Current Second Peak Angle, which showed a statistically significant difference between them. Then Bland-Altman analysis (Lancet, 1986), widely known and used for checking agreement between two different measurement methods, was conducted. It demonstrated that under almost all the experimental operating conditions, there was no agreement between the Ionization Current Second Peak Angle and the Peak Pressure Angle.

Combustion process in a spark ignition engine: analysis of cyclic peak pressure and peak pressure angle oscillations

Meccanica ◽  
2008 ◽  
Vol 44 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Grzegorz Litak ◽  
Tomasz Kamiński ◽  
Jacek Czarnigowski ◽  
Asok K. Sen ◽  
Mirosław Wendeker
Keyword(s):  
Peak Pressure ◽  
Combustion Process ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Pressure Angle

scholarly journals Ethanol/Gasoline Blends as Alternative Fuel in Last Generation Spark-Ignition Engines: A Review on CO and HC Engine Out Emissions

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 4034
Author(s):  
Paolo Iodice ◽  
Massimo Cardone
Keyword(s):  
Physicochemical Properties ◽  
Alternative Fuels ◽  
Experimental Studies ◽  
Alternative Fuel ◽  
Exhaust Emissions ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Spark Ignition Engines ◽  
The Impact

Among the alternative fuels existing for spark-ignition engines, ethanol is considered worldwide as an important renewable fuel when mixed with pure gasoline because of its favorable physicochemical properties. An in-depth and updated investigation on the issue of CO and HC engine out emissions related to use of ethanol/gasoline fuels in spark-ignition engines is therefore necessary. Starting from our experimental studies on engine out emissions of a last generation spark-ignition engine fueled with ethanol/gasoline fuels, the aim of this new investigation is to offer a complete literature review on the present state of ethanol combustion in last generation spark-ignition engines under real working conditions to clarify the possible change in CO and HC emissions. In the first section of this paper, a comparison between physicochemical properties of ethanol and gasoline is examined to assess the practicability of using ethanol as an alternative fuel for spark-ignition engines and to investigate the effect on engine out emissions and combustion efficiency. In the next section, this article focuses on the impact of ethanol/gasoline fuels on CO and HC formation. Many studies related to combustion characteristics and exhaust emissions in spark-ignition engines fueled with ethanol/gasoline fuels are thus discussed in detail. Most of these experimental investigations conclude that the addition of ethanol with gasoline fuel mixtures can really decrease the CO and HC exhaust emissions of last generation spark-ignition engines in several operating conditions.

Laminar flame speed correlations for methane, ethane, propane and their mixtures, and natural gas and gasoline for spark-ignition engine simulations

2017 ◽  
Vol 18 (9) ◽  
pp. 951-970 ◽  
Author(s):  
Riccardo Amirante ◽  
Elia Distaso ◽  
Paolo Tamburrano ◽  
Rolf D Reitz
Keyword(s):  
Natural Gas ◽  
Laminar Flame ◽  
Spark Ignition ◽  
Flame Speed ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Computational Time ◽  
Laminar Flame Speed ◽  
Spark Ignition Engines ◽  
Empirical Correlations

The laminar flame speed plays an important role in spark-ignition engines, as well as in many other combustion applications, such as in designing burners and predicting explosions. For this reason, it has been object of extensive research. Analytical correlations that allow it to be calculated have been developed and are used in engine simulations. They are usually preferred to detailed chemical kinetic models for saving computational time. Therefore, an accurate as possible formulation for such expressions is needed for successful simulations. However, many previous empirical correlations have been based on a limited set of experimental measurements, which have been often carried out over a limited range of operating conditions. Thus, it can result in low accuracy and usability. In this study, measurements of laminar flame speeds obtained by several workers are collected, compared and critically analyzed with the aim to develop more accurate empirical correlations for laminar flame speeds as a function of equivalence ratio and unburned mixture temperature and pressure over a wide range of operating conditions, namely [Formula: see text], [Formula: see text] and [Formula: see text]. The purpose is to provide simple and workable expressions for modeling the laminar flame speed of practical fuels used in spark-ignition engines. Pure compounds, such as methane and propane and binary mixtures of methane/ethane and methane/propane, as well as more complex fuels including natural gas and gasoline, are considered. A comparison with available empirical correlations in the literature is also provided.

Comparison Between Measured Radiance and a Radiation Model in a Spark-Ignition Engine

1990 ◽  
Vol 112 (3) ◽  
pp. 331-334 ◽  
Author(s):  
J. Yang ◽  
S. L. Plee ◽  
D. J. Remboski ◽  
J. K. Martin
Keyword(s):  
Heat Release ◽  
Release Rate ◽  
Maximum Rate ◽  
Spark Ignition ◽  
Rate Of Change ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Maximum Heat ◽  
Radiant Intensity ◽  
Maximum Heat Release

Measurements of the radiant emission in the near infrared have been obtained in a spark-ignition engine over a wide range of operating conditions. The system includes an in-cylinder optical sensor and associated detector. Prior work has shown correlations between the measured radiance and pressure quantities such as maximum cylinder pressure, crank angle of maximum pressure, and Indicated Mean Effective Pressure. Here are presented comparisons between the radiant intensity and a simplified model of the radiation emission, which demonstrate that the measured intensity is a function of the mass-burn fraction, mean burned-gas temperature, and the exposed combustion-chamber surface area. Further simplification leads to the conclusion that the time of the maximum rate of change of radiant intensity is the same as for the maximum heat-release rate, leading to the possibility of feedback control of spark timing. In addition, the magnitudes of the maximum rate of change of radiant emission and maximum heat-release rate have a linear relationship over a range of different operating conditions.

Model-Based Combustion Duration and Ignition Timing Prediction for Combustion Phasing Control of a Spark-Ignition Engine Using In-Cylinder Pressure Sensors

2019 ◽  
Author(s):  
Xin Wang ◽  
Amir Khameneian ◽  
Paul Dice ◽  
Bo Chen ◽  
Mahdi Shahbakhti ◽  
...  
Keyword(s):  
Pressure Sensors ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Combustion Model ◽  
Ignition Timing ◽  
Model Based ◽  
Crank Angle ◽  
Si Engines ◽  
Phasing Control

Abstract Combustion phasing, which can be defined as the crank angle of fifty percent mass fraction burned (CA50), is one of the most important parameters affecting engine efficiency, torque output, and emissions. In homogeneous spark-ignition (SI) engines, ignition timing control algorithms are typically map-based with several multipliers, which requires significant calibration efforts. This work presents a framework of model-based ignition timing prediction using a computationally efficient control-oriented combustion model for the purpose of real-time combustion phasing control. Burn duration from ignition timing to CA50 (ΔθIGN-CA50) on an individual cylinder cycle-by-cycle basis is predicted by the combustion model developed in this work. The model is based on the physics of turbulent flame propagation in SI engines and contains the most important control parameters, including ignition timing, variable valve timing, air-fuel ratio, and engine load mostly affected by combination of the throttle opening position and the previous three parameters. With 64 test points used for model calibration, the developed combustion model is shown to cover wide engine operating conditions, thereby significantly reducing the calibration effort. A Root Mean Square Error (RMSE) of 1.7 Crank Angle Degrees (CAD) and correlation coefficient (R2) of 0.95 illustrates the accuracy of the calibrated model. On-road vehicle testing data is used to evaluate the performance of the developed model-based burn duration and ignition timing algorithm. When comparing the model predicted burn duration and ignition timing with experimental data, 83% of the prediction error falls within ±3 CAD.

Investigating the Effects of Engine Operating Conditions on the Cyclic Variability of a Commercial Flex-Fuel Engine

2019 ◽  
Author(s):  
Fazal Um Min Allah ◽  
Caio Henrique Rufino ◽  
Waldyr Luiz Ribeiro Gallo ◽  
Clayton Barcelos Zabeu
Keyword(s):  
Spark Ignition ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Cylinder Pressure ◽  
Cyclic Variability ◽  
Indicated Mean Effective Pressure ◽  
Mass Fractions ◽  
Cyclic Variations ◽  
Flex Fuel ◽  
Hydrous Ethanol

Abstract The flex-fuel engines are quite capable of running on gasohol and hydrous ethanol. However, the in-cylinder cyclic variations, which are inherently present in spark-ignition (SI) engines, affect the performance of these engines. Therefore, a comprehensive analysis is required to evaluate the effects of in-cylinder cyclic variations of a flex-fuel engine. The experiments were carried out by using Brazilian commercial Gasohol E27 (mixture of 27% anhydrous ethanol in gasoline) and hydrous ethanol E95h (5% water by volume in ethanol) as fuels for a commercial flex-fuel spark ignition engine. A comparison between the cyclic variations of gasohol and hydrous ethanol is presented in this paper. Moreover, the effects of engine operating parameters (i.e., engine speed, engine load and relative air fuel ratio) on cyclic variations are also investigated. The acquired data of in-cylinder pressure and combustion durations are evaluated by carrying out a statistical analysis. The coefficient of variation for indicated mean effective pressure (IMEP) did not exceed the limit of 5% for all tested conditions. Higher cyclic variability of maximum in-cylinder pressure is observed for gasohol fuel and higher engine speeds. The variability of in-cylinder combustion is also evaluated with the help of different combustion stages, which are characterized by corresponding crank positions of 10%, 50% and 90% mass fractions burned.

Development of the Control and Acquisition System for a Natural-Gas Spark-Ignition Engine Test Bench

2019 ◽  
Author(s):  
Lorenzo Gasbarro ◽  
Jinlong Liu ◽  
Christopher Ulishney ◽  
Cosmin E. Dumitrescu ◽  
Luca Ambrogi ◽  
...  
Keyword(s):  
Natural Gas ◽  
Internal Combustion Engines ◽  
Test Bench ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Acquisition System ◽  
Combustion Engines ◽  
Engine Test ◽  
New Sensors

Abstract Investigations using laboratory test benches are the most common way to find the technological solutions that will increase the efficiency of internal combustion engines and curtail their emissions. In addition, the collected experimental data are used by the CFD community to develop engine models that reduce the time-to-market. This paper describes the steps made to increase the reliability of engine experiments performed in a heavy-duty natural-gas spark-ignition engine test-cell such as the design of the control and data acquisition system based on Modbus TCP communication protocol. Specifically, new sensors and a new dynamometer controller were installed. The operation of the improved test bench was investigated at several operating conditions, with data obtained at both high- and low-sampling rates. The results indicated a stable test bench operation.

scholarly journals Improving Fuel Economy of Spark Ignition Engines Applying the Combined Method of Power Regulation

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1076 ◽  
Author(s):  
Yurii Gutarevych ◽  
Vasyl Mateichyk ◽  
Jonas Matijošius ◽  
Alfredas Rimkus ◽  
Igor Gritsuk ◽  
...  
Keyword(s):  
Fuel Economy ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Spark Ignition Engines ◽  
Combined Method ◽  
Research Results ◽  
Fuel Supply ◽  
Power Regulation ◽  
Engine Power

One of the disadvantages of spark ignition engines, whose power is regulated by throttling, is the increased fuel consumption at low loads and when the engine is idle. The combined method of engine power regulation by switching off the cylinder group and throttling working cylinders is one of the effective ways to improve fuel economy in the above-mentioned modes. This article presents the research results of the combined method of engine power regulation which can be realized by minor structural changes in operating conditions. The method implies the following: at low loads and at idle speed of the engine. Fuel supply to the group of cylinders is switched off with the simultaneous increase of the cyclic fuel supply in the working cylinders. The adequacy of the calculated results has been checked by the indication of operating processes in switched off and working cylinders. The research results of a six-cylinder spark ignition engine with the distributed gasoline injection using the combined power regulation system have been shown. The angles of opening the throttle which provides a non-shock transition from the operation with all cylinders to the operation with the cylinder group switched off have been determined.

Observer-Based Cylinder Air Charge Estimation for Spark-Ignition Engines

2017 ◽  
Vol 139 (10) ◽  
Author(s):  
Zhe Wang ◽  
Qilun Zhu ◽  
Robert Prucka ◽  
Michael Prucka ◽  
Hussein Dourra
Keyword(s):  
Steady State ◽  
Rapid Prototype ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Estimation Methods ◽  
Absolute Pressure ◽  
Spark Ignition Engines ◽  
Engine Torque ◽  
Advantages And Disadvantages

Spark-ignition engine in-cylinder air charge estimation is important for air-to-fuel ratio (AFR) control, maintaining high after-treatment efficiency, and determination of current engine torque. Current cylinder air charge estimation methodologies generally depend upon either a mass air flow (MAF) sensor or a manifold absolute pressure (MAP) sensor individually. Methods based on either sensor have their own advantages and disadvantages. Some production vehicles are equipped with both MAF and MAP sensors to offer air charge estimation and other benefits. This research proposes several observer-based cylinder air charge estimation methods that take advantage of both MAF and MAP sensors to potentially reduce calibration work while providing acceptable transient and steady-state accuracy with low computational load. This research also compares several common air estimation methods with the proposed observer-based algorithms using steady-state and transient dynamometer tests and a rapid-prototype engine controller. With appropriate tuning, the proposed observer-based methods are able to estimate cylinder air charge mass under different engine operating conditions based on the manifold model and available sensors. Methods are validated and compared based on a continuous tip-in tip-out operating condition.

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