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Viewing 91 to 120 of 23234
2016-04-05
Technical Paper
2016-01-0788
Xiangyu Meng, Karthik Nithyanandan, Timothy Lee, Yuqiang Li, Wuqiang Long, Chia-Fon Lee
Abstract In order to comply with the stringent emission regulations, many researchers have been focusing on diesel-compressed natural gas (CNG) dual fuel operation in compression ignition (CI) engines. The diesel-CNG dual fuel operation mode has the potential to reduce both the soot and NOx emissions; however, the thermal efficiency is generally lower than that of the pure diesel operation, especially under the low and medium load conditions. The current experimental work investigates the potential of using diesel-1-butanol blends as the pilot fuel to improve the engine performance and emissions. Fuel blends of B0 (pure diesel), B10 (90% diesel and 10% 1-butanol by volume) and B20 (80% diesel and 20% 1-butanol) with 70% CNG substitution were compared based on an equivalent input energy at an engine speed of 1200 RPM. The results indicated that the diesel-1-butanol pilot fuel can lead to a more homogeneous mixture due to the longer ignition delay.
2016-04-05
Technical Paper
2016-01-0787
Valentin Soloiu, Martin Muinos, Spencer Harp, Tyler Naes, Remi Gaubert
Abstract In this study, Premixed Charge Compression Ignition (PCCI) was investigated with alternative fuels, S8 and n-butanol. The S8 fuel is a Fischer Tropsch (FT) synthetic paraffinic kerosene (SPK) produced from natural gas. PCCI was achieved with a dual-fuel combustion incorporating 65% (by mass) port fuel injection (PFI) of n-butanol and 35% (by mass) direct injection (DI) of S8 with 35% exhaust gas recirculation. The experiments were conducted at 1500 rpm and varied loads of 1-5 bar brake mean effective pressure (BMEP). The PCCI tests were compared to an ultra-low sulfur diesel no. 2 (ULSD#2) baseline in order to determine how the alternative fuels effects combustion, emissions, and efficiencies. At 3 and 5 bar BMEP, the heat release in the PCCI mode exhibited two regions of high temperature heat release, one occurring near top dead center (TDC) and corresponds to the ignition of S8 (CN 62), and a second stage occurring ATDC from n-butanol combustion (CN 28).
2016-04-05
Technical Paper
2016-01-0611
Dejan Kihas, Daniel Pachner, Lubomir Baramov, Michael Uchanski, Priya Naik, Nassim Khaled
Abstract The interest for NOx estimators (also known as virtual sensors or inferential sensors) has increased over the recent years due to benefits attributed to cost and performance. NOx estimators are typically installed to improve On-Board Diagnostics (OBD) monitors or to lower bill of material costs by replacing physical NOx sensors. This paper presents initial development results of a virtual engine-out NOx estimator planned for the implementation on an ECM. The presented estimator consists of an airpath observer and a NOx combustion model. The role of the airpath observer is to provide input values for the NOx combustion model such as the states of the gas at the intake and exhaust manifolds. It contains a nonlinear mean-value model of the airpath suitably transformed for an efficient and robust implementation on an ECM. The airpath model uses available sensory information in the vehicle to correct predictions of the gas states.
2016-04-05
Technical Paper
2016-01-0612
Rohit Koli, Konstantinos Siokos, Robert Prucka, Shyam Jade, Jason Schwanke
Abstract Low-pressure cooled EGR (LP-cEGR) systems can provide significant improvements in spark-ignition engine efficiency and knock resistance. However, open-loop control of these systems is challenging due to low pressure differentials and the presence of pulsating flow at the EGR valve. This research describes a control structure for Low-pressure cooled EGR systems using closed loop feedback control along with internal model control. A Smith Predictor based PID controller is utilized in combination with an intake oxygen sensor for feedback control of EGR fraction. Gas transport delays are considered as dead-time delays and a Smith Predictor is one of the conventional methods to address stability concerns of such systems. However, this approach requires a plant model of the air-path from the EGR valve to the sensor.
2016-04-05
Technical Paper
2016-01-0616
Jayant Sarlashkar, Sankar Rengarajan, Ryan Roecker
Abstract Southwest Research Institute (SwRI) has successfully demonstrated the cooled EGR concept via the High Efficiency Dilute Gasoline Engine (HEDGE) consortium. Dilution of intake charge provides three significant benefits - (1) Better Cycle Efficiency (2) Knock Resistance and (3) Lower NOx/PM Emissions. But EGR dilution also poses challenges in terms of combustion stability, condensation and power density. The Dedicated EGR (D-EGR) concept brings back some of the stability lost due to EGR dilution by introducing reformates such as CO and H2 into the intake charge. Control of air, EGR, fuel, and ignition remains a challenge to realizing the aforementioned benefits without sacrificing performance and drivability. This paper addresses the DEGR solution from a controls standpoint. SwRI has been developing a unified framework for controlling a generic combustion engine (gasoline, diesel, dual-fuel natural gas etc.).
2016-04-05
Technical Paper
2016-01-0618
Feilong Liu, Jeffrey M. Pfeiffer, Ron Caudle, Peter Marshall, Peter Olin
Abstract Low Pressure Cooled Exhaust Gas Recirculation (LP EGR) is an attractive technology to reduce fuel consumption for a spark-ignition (SI) engine, particularly at medium-to-high load conditions, due to its knock suppression and combustion cooling effects. However, the long LP EGR transport path presents a significant challenge to the transient control of LP EGR for the engine management system. With a turbocharged engine, this is especially challenging due to the much longer intake induction system path compared with a naturally aspirated engine. Characterizing and modeling the EGR, intake air mixing and transport delay behavior is important for proper control. The model of the intake air path includes the compressor, intercooler and intake plenum. It is important to estimate and track the final EGR concentration at the intake plenum location, as it plays a key role in combustion control.
2016-04-05
Technical Paper
2016-01-0631
Emilio Navarro-Peris, Estefanía Hervas-Blasco, José M. Corberan, Alex Rinaldi
Abstract The present concern in the reduction of CO2 emissions occasioned by heavy duty trucks is leading to a technological evolution, among others, in powertrain electrification. Towards this objective, the EU has funded the project GASTone targeting the development of a new powertrain concept based on the energy recovery from the exhaust gases and kinetic losses in order to make possible the electrification of the main auxiliaries. This new concept will follow a cascade approach in which the exhaust gases energy will be recovered by the integration of an advanced thermoelectric generator followed by a turbo-generator. This system will be combined with a smart kinetic energy recovery device which will recover the energy losses in the deceleration periods of the vehicle. The recovered energy will be used in the electrified auxiliaries.
2016-04-05
Technical Paper
2016-01-0691
Gurneesh S. Jatana, Brian C. Kaul, Robert Wagner
Abstract Spark-ignition (SI) engines can derive substantial efficiency gains from operation at high dilution levels, but sufficiently high-dilution operation increases the occurrence of misfires and partial burns, which induce higher levels of cyclic-variability in engine operation. This variability has been shown to have both stochastic and deterministic components, with residual fraction impacts on charge composition being the major source of the deterministic component through its non-linear effect on ignition and flame propagation characteristics. This deterministic coupling between cycles offers potential for next-cycle control approaches to allow operation near the edge of stability. This paper aims to understand the effect of spark strategies, specifically the use of a second spark (restrike) after the main spark, on the deterministic coupling between engine cycles by operating at high dilution levels using both excess air (i.e. lean combustion) and EGR.
2016-04-05
Technical Paper
2016-01-0683
Kai Morganti, Abdullah Alzubail, Marwan Abdullah, Yoann Viollet, Robert Head, Junseok Chang, Gautam Kalghatgi
Abstract This paper is the second of a two part study which investigates the use of advanced combustion modes as a means of improving the efficiency and environmental impact of conventional light-duty vehicles. This second study focuses on drive cycle simulations and Life Cycle Assessment (LCA) for vehicles equipped with Octane-on-Demand combustion. Methanol is utilized as the high octane fuel, while three alternative petroleum-derived fuels with Research octane numbers (RONs) ranging from 61 to 90 are examined as candidates for the lower octane fuel. The experimental engine calibration maps developed in the previous study are first provided as inputs to a drive cycle simulation tool. This is used to quantify the total fuel consumption, octane requirement and tank-to-wheel CO2 emissions for a light-duty vehicle equipped with two alternative powertrain configurations.
2016-04-05
Technical Paper
2016-01-0678
Haifeng Lu, Jun Deng, Zongjie Hu, Zhijun Wu, Liguang Li, Fangen Yuan, Degang Xie, Shuang Yuan, Yuan Shen
Abstract This research was concerned with the use of Exhaust Gas Recirculation (EGR) improving the fuel economy over a wide operating range in a downsized boosted gasoline engine. The experiments were performed in a 1.3-Litre turbocharged PFI gasoline engine, equipped with a Low Pressure (LP) water-cooled EGR system. The operating conditions varied from 1500rpm to 4000rpm and BMEP from 2bar to 17bar. Meanwhile, the engine’s typical operating points in NEDC cycle were tested separately. The compression ratio was also changed from 9.5 to 10.5 to pursue a higher thermal efficiency. A pre-compressor throttle was used in the experiment working together with the EGR loop to keep enough EGR rate over a large area of the engine speed and load map. The results indicated that, combined with a higher compression ratio, the LP-EGR could help to reduce the BSFC by 9∼12% at high-load region and 3∼5% at low-load region.
2016-04-05
Technical Paper
2016-01-0697
Francesco Catapano, Silvana Di Iorio, Ludovica Luise, Paolo Sementa, Bianca Maria Vaglieco
Abstract In this paper, the effect of the oxygen addition on engine performance and exhaust emissions was investigated. The experimental study was carried out in a small single-cylinder PFI SI four-stroke engine. The addition of the 5% vol and 10% vol of oxygen was performed in the intake duct. Typical urban driving operating conditions were investigated. The engine emissions were characterized by means of gaseous analyzers and a smokemeter. Particle size distribution function was measured in the size range from 5.6 to 560 nm by means of an Engine Exhaust Particle Sizer (EEPS). An improvement in terms of engine power output, without BSFC penalty, and HC emissions with oxygen addition was observed at all the investigated operating conditions. On the other hand, NOx and PM emissions increase.
2016-04-05
Technical Paper
2016-01-0698
Zheng Xu, Zhou Zhou, Tao Wu, Tong Li, Chuanhui Cheng, Haiting Yin
Abstract Engine downsizing has become a leading trend for fuel consumption reduction while maintaining the high specific power and torque output. Because of this, Turbo-charged Gasoline Direct Injection (TGDI) technology has been widely applied in passenger vehicles even though a number of technical challenges are presented during the engine development. This paper presents the investigation results of three key issues in the combustion development of a 2.0L TGDI engine at SAIC motor: fuel dilution, smoke emission and low speed stochastic pre-ignition(LSPI). The effect of the injection timing and injection strategy on fuel dilution and smoke emission, and LSPI are the focus of the experimental study.
2016-04-05
Technical Paper
2016-01-0646
Pablo Olmeda, Jaime Martin, Antonio Garcia, Diego Blanco, Alok Warey, Vicent Domenech
Abstract Regulated emissions and fuel consumption are the main constraints affecting internal combustion engine (ICE) design. Over the years, many techniques have been used with the aim of meeting these limitations. In particular, exhaust gas recirculation (EGR) has proved to be an invaluable solution to reduce NOx emissions in Diesel engines, becoming a widely used technique in production engines. However, its application has a direct effect on fuel consumption due to both the changes in the in-cylinder processes, affecting indicated efficiency, and also on the air management. An analysis, based on the engine Global Energy Balance, is presented to thoroughly assess the behavior of a HSDI Diesel engine under variable EGR conditions at different operating points. The tests have been carried out keeping constant the conditions at the IVC and the combustion centering.
2016-04-05
Technical Paper
2016-01-0676
Mohamed Shaaban Khalef, Alec Soba, John Korsgren
Abstract An experimental study of EGR and turbocharging concepts has been performed on an experimental 2.0-litre 4-cylinder turbocharged Euro6 light-duty diesel engine. The purpose of the study was to investigate the emissions and fuel consumption trade-off for different concept combinations. The impact of low-pressure and high-pressure EGR was studied in terms of engine-out emissions and fuel consumption. Moreover, the influence of single-stage and two-stage turbocharging was investigated in combination with the EGR systems, and how the engine efficiency could be further improved after engine calibration optimization. During low load engine operation where throttling may be required to achieve the desired low-pressure EGR rate, the difference in fuel consumption impact was studied for exhaust throttling and intake throttling, respectively. The cooling impact on high-pressure EGR was compared in terms of emissions and fuel consumption.
2016-04-05
Technical Paper
2016-01-0194
Yici Li, Wei Tian
Abstract The exhaust cooling is an important index which measures the performance of the flameproof diesel engine. In this paper, a modification model is built for enhancing the cooling performance of exhaust, based on the reference model of the dry cooling equipment. The annular nozzle direction, extend plate of guide, bellows and elbow are introduced and studied in the model as the modification way. Considering the Coanda and Venturi effects, the comprehensive comparison of fluid velocity, temperature, pressure and mixture coefficient is implemented, and the optimum horizontal dimension of throat is summarized. The simulation results indicate the modification model shows better performance in reducing exhaust temperature and pressure than the reference model.
2016-04-05
Journal Article
2016-01-0186
Hyunki Sul, Taehoon Han, Mitchell Bieniek, John Hoard, Chih-Kuang Kuan, Daniel Styles
Abstract Exhaust gas recirculation (EGR) coolers are used on diesel engines to reduce peak in-cylinder flame temperatures, leading to less NOx formation during the combustion process. There is an ongoing concern with soot and hydrocarbon fouling inside the cold surface of the cooler. The fouling layer reduces the heat transfer efficiency and causes pressure drop to increase across the cooler. A number of experimental studies have demonstrated that the fouling layer tends to asymptotically approach a critical height, after which the layer growth ceases. One potential explanation for this behavior is the removal mechanism derived by the shear force applied on the soot and hydrocarbon deposit surface. As the deposit layer thickens, shear force applied on the fouling surface increases due to the flow velocity growth. When a critical shear force is applied, deposit particles start to get removed.
2016-04-05
Technical Paper
2016-01-0550
Zhijia Yang, Edward Winward, Gary O'Brien, Richard Stobart, Dezong Zhao
Abstract The intrinsic model accuracy limit of a commonly used Exhaust Gas Recirculation (EGR) mass flow rate model in diesel engine air path control is discussed in this paper. This EGR mass flow rate model is based on the flow of a compressible ideal gas with unchanged specific heat ratio through a restriction cross-area within a duct. A practical identification procedure of the model parameters is proposed based on the analysis of the engine data and model structure. This procedure has several advantages which include simplicity, low computation burden and low engine test cost. It is shown that model tuning requires only an EGR valve sweep test at a few engine steady state operating points.
2016-04-05
Technical Paper
2016-01-0547
Andrea Piano, Federico Millo, Giulio Boccardo, Mahsa Rafigh, Alessandro Gallone, Marcello Rimondi
The predictive capabilities of an innovative multizone combustion model DIPulse, developed by Gamma Technologies, were assessed in this work for a last generation common rail automotive diesel engine. A detailed validation process, based on an extensive experimental data set, was carried out concerning the predicted heat release rate, the in-cylinder pressure trace, as well as NOx and soot emissions for several operating points including both part load and full load points. After a preliminary calibration of the model, the combustion model parameters were then optimized through a Latin Hypercube Design of Experiment (DoE), with the aim of minimizing the RMS error between the predicted and experimental burn rate of several engine operating points, thus achieving a satisfactory agreement between simulation and experimental engine combustion and emissions parameters.
2016-04-05
Technical Paper
2016-01-0548
Estefanía Hervas-Blasco, Emilio Navarro-Peris, José Corberan, Alex Rinaldi
Abstract Nowadays, more than 50% of the fuel energy is lost in CNG Engines. While efforts to increase their efficiency have been focused mainly on the improvement of the combustion process, the combustion chamber and the reduction of friction losses, heat losses still remain the most important inefficient factor. A global strategy in which several energy recovery strategies are implemented could lead to engine improvements up to 15%. Therefore, the development of accurate models to size and predict the performance of the integrated components as well as to define an optimized control strategy is crucial. In this contribution, a model to analyze the potential of a new powertrain based on the electrification of the main auxiliaries, the integration of a kinetic energy recovery system and the exhaust gases heat recovery through a thermoelectric generator and a turbo-component is presented.
2016-04-05
Technical Paper
2016-01-0558
Christoph Poetsch, Tomaz Katrasnik
Abstract The present work introduces an innovative mechanistically based 0D spray model which is coupled to a combustion model on the basis of an advanced mixture controlled combustion approach. The model calculates the rate of heat release based on the injection rate profile and the in-cylinder state. The air/fuel distribution in the spray is predicted based on momentum conservation by applying first principles. On the basis of the 2-zone cylinder framework, NOx emissions are calculated by the Zeldovich mechanism. The combustion and emission models are calibrated and validated with a series of dedicated test bed data specifically revealing its capability of describing the impact of variations of EGR, injection timing, and injection pressure. A model based optimization is carried out, aiming at an optimum trade-off between fuel consumption and engine-out emissions. The findings serve to estimate an economic optimum point in the NOx/BSFC trade-off.
2016-04-05
Technical Paper
2016-01-0553
Akira Miyamoto, Kenji Inaba, Yukiko Obara, Yukie Ishizawa, Emi Sato, Mai Sase, Patrick Bonnaud, Ryuji Miura, Ai Suzuki, Naoto Miyamoto, Nozomu Hatakeyama, Jun Hashimoto, Kazuhiro Akihama
Abstract Suppression or reduction of soot emissions is an important goal in the development of automotive engines for environmental and human health purposes. A better understanding at the molecular level of the formation process of soot particles resulting from collision and aggregation of smaller particles made of Polycyclic Aromatic Hydrocarbon (PAH) is needed. In addition to experiments, computational methods are efficient and valuable tools for this purpose. As a first step in our detailed computational chemistry study, we applied Ultra-Accelerated Molecular Dynamics (UAQCMD) and Canonical Monte-Carlo (CMC) methods to investigate the nucleation process. The UA-QCMD can calculate chemical reaction dynamics 107 times faster than conventional first principle molecular dynamics methods, while CMC can calculate equilibrium properties at various temperatures, pressures, and chemical compositions.
2016-04-05
Technical Paper
2016-01-0561
Seungha Lee, Youngbok Lee, Kyoungchan Han, Kyoung Min Lee, Jun Yu, Junyong Lee, Kyoungdoug Min
Abstract Currently, diesel engine-out exhaust NOx emission level prediction is a major challenge for complying with the stricter emission legislation and for control purpose of the after-treatment system. Most of the NOx prediction research is based on the Zeldovich thermal mechanism, which is reasonable from the physical point of view and for its simplicity. Nevertheless, there are some predictable range limitations, such as low temperature with high EGR rate operating conditions or high temperature with low EGR rates. In the present paper, 3 additional considerations, pilot burned gas mixing before the main injection; major NO formation area; concentration correction, were applied to the previously developed real-time NO estimation model based on in-cylinder pressure and data available from ECU. The model improvement was verified on a 1.6 liter EURO5 diesel engine in both steady and transient operation.
2016-04-05
Technical Paper
2016-01-1291
Greig Latham
Abstract Applying the Economic Input-Output Life Cycle Assessment (EIOLCA) method to the question of fielding newly manufactured or remanufactured vehicles provides an illuminating view of the economic and environmental advantages of remanufacturing. Sustained accomplishments of policy and engineering have reduced vehicle emissions such that current work has reached the point of diminishing returns. The macroeconomic, global, unprecedented, debt-supercycle-combined with increasing costs of natural resource extraction and vehicle production-demands improved asset and resource utilization. Expanding and exploiting the entire vehicle life cycle is a profitable and sustainable extension of work to date; such extension calls for remanufacturing to move from vehicle components to the entire vehicle. Stretching service lifetimes delay traditional end-of-life recovery practices while radically challenging the status quo.
2016-04-05
Technical Paper
2016-01-1290
J. Groenewald, James Marco, Nicholas Higgins, Anup Barai
Abstract While a number of publications have addressed the high-level requirements of remanufacturing to ensure its commercial and environmental sustainability, considerably less attention has been given to the technical data and associated test strategies needed for any evidence-based decision as to whether a vehicle energy storage system should be remanufactured - extending its in-vehicle life, redeployed for second-life (such as domestic or grid storage) or decommissioned for recycling. The aim of this paper is to critically review the strategic requirements for data at the different stages of the battery value-chain that is pertinent to an Electric Vehicle (EV) battery remanufacturing strategy. Discussed within the paper is the derivation of a feasible remanufacturing test strategy for the vehicle battery system.
2016-04-05
Technical Paper
2016-01-1292
Manish Dixit, V Sundaram, Sathish Kumar S
Abstract Noise pollution is a major concern for global automotive industries which propels engineers to evolve new methods to meet passenger comfort and regulatory requirements. The main purpose of an exhaust system in an automotive vehicle is to allow the passage of non-hazardous gases to the atmosphere and reduce the noise generated due to the engine pulsations. The objective of this paper is to propose a Design for Six Sigma (DFSS) approach followed to optimize the muffler for better acoustic performance without compromising on back pressure. Conventionally, muffler design has been an iterative process. It involves repetitive testing to arrive at an optimum design. Muffler has to be designed for better acoustics performance and reduced back pressure which complicates the design process even more.
2016-04-05
Technical Paper
2016-01-1286
Takuya Hara, Takahiro Shiga, Kazutaka Kimura, Akinori Sato
Abstract Introducing effective technologies to reduce carbon emissions in the transport sector is a critical issue for automotive manufacturers to contribute to sustainable development. Unlike the plug-in electric vehicles (PEVs), whose effectiveness is dependent on the carbon intensity of grid electricity, the solar hybrid vehicle (SHV) can be an alternative electric vehicle because of its off-grid, zero-emission electric technology. Its usability is also advantageous because it does not require manual charging by the users. This study aims at evaluating the economic, environmental, and usability benefits of SHV by comparing it with other types of vehicles including PEVs. By setting cost and energy efficiency on the basis of the assumed technology level in 2030, annual cost and annual CO2 emissions of each vehicle are calculated using the daily mileage pattern obtained from a user survey of 5,000 people in Japan and the daily radiation data for each corresponding user.
2016-04-05
Technical Paper
2016-01-1285
Xiang Cheng, Han Hao, Zongwei Liu, Fuquan Zhao
Abstract Compared with conventional vehicles, electric vehicles (EVs) offer the benefits of replacing petroleum consumption and reducing air pollutions. However, there have been controversies over greenhouse gas (GHG) emissions of EVs from the life-cycle perspective in China’s coal-dominated power generation context. Besides, it is in doubt whether the cost-effectiveness of EVs in China exceeds other fuel-efficient vehicles considering the high prices. In this study, we compared the life-cycle GHG emissions of existing vehicle models in the market. Afterwards, a cost model is established to compare the total costs of vehicles. Finally, the cost-effectiveness of different vehicle types are compared. It is concluded that the GHG emission intensity of EVs is lower than reference and hybrid vehicles currently and is expected to decrease with the improvement of the power grid.
2016-04-05
Technical Paper
2016-01-1287
Kazutaka Kimura, Yuki Kudo, Akinori Sato
Abstract In recent years, automakers have been developing various types of environmentally friendly vehicles such as hybrid (HV), plug-in hybrid (PHV), electric (EV), and fuel cell (FCV) vehicles to help reduce greenhouse gas (GHG) emissions. However, there are few commercial solar vehicles on the market. One of the reasons why automakers have not focused attention on this area is because the benefits of installing solar modules on vehicles under real conditions are unclear. There are two difficulties in measuring the benefits of installing solar modules on vehicles: (1) vehicles travel under various conditions of sunlight exposure and (2) sunlight exposure conditions differ in each region. To address these problems, an analysis was performed based on an internet survey of 5,000 people and publically available meteorological data from 48 observation stations in Japan.
2016-04-05
Technical Paper
2016-01-0010
Gopal Athani, Kapil Dongare, Srinivasa Raju Gavarraju, Shashi Kulkarni, Prasad Yerraguntla
Abstract Micro hybrid Systems are emerging as a promising solution to reduce the fuel consumption and greenhouse gas emissions in emerging markets, where the strict emission requirements are being enforced gradually. Micro hybrid Systems reduce the fuel consumption and greenhouse gas emissions in a conventional vehicle with 12 V electrical system, by optimizing the electrical energy generation, storage, and distribution, with functions like Intelligent Alternator Control, Engine Stop/Start, and Load Management. With the advent of Connected Car Systems, information about the vehicle is seamlessly provided to the customer not just through the Human Machine Interface systems within the vehicle, but to other mobile devices used by the customers.
2016-04-05
Technical Paper
2016-01-0044
Sung Yul Chu, Sung Eun Jo, Kyoungbok Lee, Kwang Chul Oh, Jong Rim Lee
Abstract On-board diagnostics (OBD) of diesel vehicles require various sensors to detect system malfunctions. The Particulate Matter (PM) sensor is one of OBD devices which gather information which could be critical in determining a crack in the diesel particulate filters (DPFs). The PM sensor detects PM which penetrates cracked DPFs and converts the amount of PM into electrical values. The PM sensor control unit (SCU) receives those analog signals and converts them to digital values through hardware and software solutions. A capacitive sensing method would be a stable solution because it detects not raw analog signals but electrical charges or a time constant going through the capacitive load. Therefore, amount of PM would be converted reasonable value of capacitance even though there is a little amount of PM.
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