Cost implications of various Euro 4 and 5 after treatment solutions for heavy duty diesel vehicles

This study is firstly a short review of the types of exhaust systems predicted for Euro 4 (2005) and Euro 5 (2008), particularly focussed on the effects of combined NOx (nitrogen oxides) and PM (particulate matter) aftertreatment systems. Secondly, it explores in detail the implications of using a liquid secondary water-based fuel of urea on board heavy duty diesel vehicles in Europe as a basis for NOx reduction via selective catalytic reduction (SCR). Some of the main points that become apparent when using integrated SCR systems are: the potential costs of increased urea production in Europe (including possible fuel taxation), refuelling issues, secondary fuel cost, logistics of urea supply, and cost of implementation of the urea fuel delivery method. From the original equipment manufacturers view, the hardware cost will be increased substantially when compared to current silencer systems. From the vehicle owner’s point of view, the possibility of large running cost increases is not desired, and the system solution cost and its benefits must ultimately be acceptable. This paper will attempt to put the life-time costs of various systems within perspective in order to assess the feasibility of implementing selective catalytic reduction systems (SCR) Europe wide for the near future

Development of an Ammonia Reduction After-Treatment Systems for Stoichiometric Natural Gas Engines

Three-way catalyst (TWC) equipped stoichiometric natural gas vehicles have proven to be an effective alternative fuel strategy that shows significant low NOx emissions characteristics. However, recent studies have shown the TWC activity to contribute to elevated levels of tailpipe ammonia (NH 3) emissions. Although a non-regulated pollutant, ammonia is a potent pre-cursor to ambient secondary PM formation. Ammonia is an inevitable byproduct of fuel rich operation that results in lowest NOx slip through the TWC after-treatment system.;The main objective of the study is to develop a passive Ammonia Reduction Catalyst (passive-ARC) based NH3 reduction strategy that results in an overall reduction of ammonia as well as NOx emissions. The study investigated the characteristics of Fe-based and Cu-based zeolites SCR catalysts in storage and desorption of ammonia at high exhaust temperature conditions, that are typical of stoichiometric natural gas engines. Continuous measurements of NOx and NH3 before and after the SCR systems were conducted using a Fourier Transform Infrared Spectrometry (FTIR) gas analyzer. Results of the investigation showed that both, the Fe- and Cu zeolite SCRs adsorbed above 90% of TWC generated NH3 emissions below 350--375 °C SCR temperatures. Desorption or slipping of NH3 was observed at exhaust gas temperatures exceeding 400 °C. In terms of NOx conversions, Fe-zeolite showed efficiency between 50--80% above temperatures of 300--350 °C while Cu-zeolite performed well at lower SCR temperature from 250 °C and above with a conversion efficiency of greater than 50%.;In order to efficiently reduce both NOx and NH3 simultaneously over longer durations it was found that an engine-based air fuel ratio operation strategy for the passive-ARC system must be developed. To this extent, the study extended its objectives to develop an engine-based control strategy that results in stoichiometric ammonia production operation followed by brief lean operation to regenerate the saturated ammonia reduction catalyst using high NOx slip through TWC. The study presents comprehensive results of ammonia storage characteristics of SCRs pertaining to stoichiometric natural gas engine exhaust as well as an advanced engine control strategy approach to simultaneously reduce both NOx and NH3 using an alternating air -fuel ratio approach

Control-oriented modelling and diagnostics of diesel after-treatment catalysts

[ES] Esta tesis doctoral abarca el desarrollo de algoritmos orientados a mejorar el sistema de control de emisiones en motores Diesel. Para este propósito, la inclusión en el vehículo de sensores embarcados como los de temperatura, los de NOx o el de NH3 permite realizar diagnóstico a bordo de los sistemas de post-tratamiento foco de este trabajo, los cuales son el DOC y el SCR. Así pues, el objetivo es el de satisfacer las normativas de diagnóstico a bordo para mantener las emisiones por debajo del umbral permitido por la normativa a lo largo del tiempo. Los tests experimentales, incluyendo las medidas con analizador de gases, permiten tener una visión más amplia de las especies en la línea de escape. Complementariamente, se utilizan unidades nuevas y envejecidas para tener el efecto experimental del envejecimiento en los catalizadores. De esta manera, se analiza el efecto de la temperatura, el gasto de escape, las concentraciones de las especies y el envejecimiento en el DOC y en el SCR, así como la evaluación de algunas de las medidas relevantes realizadas por los sensores. Las temperaturas tienen una influencia destacada en el funcionamiento de los catalizadores, por lo que se requiere la evaluación de las medidas de los sensores de temperatura, junto con el desarrollo de modelos de transmisión de calor, para alimentar las funciones a continuación desarrolladas. En este sentido, la medida lenta del sensor aguas arriba del DOC se mejora en condiciones transitorias mediante una técnica de fusión de la información basada en un filtro de Kalman. Luego, se presenta un modelo de transmisión de calor 1D y un modelo agrupado 0D, en los cuales se evalúan las entradas aguas arriba según el uso del modelo. Por otra parte, se presenta una técnica para estimar el incremento de temperatura debido a la oxidación de los pulsos de post-inyección en el DOC. Se proponen modelos para ambos DOC y SCR para estimar el efecto del envejecimiento en las emisiones, en los cuales el factor de envejecimiento es modelado como un parámetro sintonizable que permite variar desde estados nuevos a envejecidos. Por una parte, un modelo agrupado 0D es desarrollado para el DOC con el propósito de estimar el desliz de HC y CO, el cual es validado en un WLTC para después ser usado en simulación. Por otra parte, un modelo 1D y un modelo 0D se desarrollan para el SCR, los cuales se usan a continuación para alimentar la estrategia de diagnóstico y para simulación. Finalmente, las estrategias de diagnóstico se presentan para fallo total o retirada de DOC, así como para la estimación de la eficiencia en DOC y SCR. Por una parte, la primera estrategia se divide en pasiva y activa, en la que se usan post-inyecciones en la activa para excitar el sistema y confirmar el fallo total si es el caso. A continuación, la eficiencia del DOC se estima a través de una técnica indirecta en la que la temperatura de activación se detecta y se relaciona con el incremento de emisiones a través del modelo. Por otra parte, se desarrolla un observador para estimar el estado de envejecimiento del SCR, el cual está basado en un filtro de Kalman extendido. Sin embargo, para evitar asociar baja eficiencia del catalizador debido a pobre calidad de la urea inyectada, a envejecimiento del SCR, un indicador de la calidad de la urea se ejecuta en paralelo.[CA] Esta tesi doctoral abasta el desenvolupament d'algoritmes orientats a millor el sistema de control d'emissions en motors Diesel. Per a este propòsit, la inclusió en el vehicle de sensor embarcats com els de temperatura, els de NOx o el d'NH3 permet realitzar el diagnòstic a bord dels sistemes de post-tractament focus d'este treball, els quals són el DOC i el SCR. Així doncs, l'objectiu és el de satisfer les normatives de diagnòstic a bord per a mantindre les emissions per baix de l'umbral permés per la normativa al llarg del temps. Els tests experimentals, incloent les mesures amb analitzador de gasos, permeten obtindre una visió més àmplia de les espècies en la línia d'escapament. Complementàriament, s'utilitzen unitats noves i envellides per tal de tindre l'efecte experimental de l'envelliment en els catalitzadors. D'aquesta manera, s'analitza l'efecte de la temperatura, la despesa d'escapament, les concentracions de les espècies i l'envelliment en el DOC i en el SCR, així com l'avaluació d'algunes mesures rellevants realitzades pels sensors. Les temperatures tenen una influència destacada en el funcionament dels catalitzadors, pel que es requerix l'avaluació de les mesures dels sensors de temperatura, junt amb el desenvolupament de models de transmissió de calor, per a alimentar les funcions a continuació desenvolupades. En este sentit, la mesura lenta del sensor a l'entrada del DOC es millora en condicions transitòries mitjançant una tècnica de fusió de la informació basada en un filtre de Kalman. Després, es presenta un model de transmissió de calor 1D i un model agrupat 0D, en els quals s'avaluen les entrades a l'entrada segons l'ús del model. Per altra banda, es presenta una tècnica per a estimar l'increment de temperatura degut a l'oxidació dels polsos de post-injecció en el DOC. Es proposen models per a DOC i SCR per a estimar l'efecte de l'envelliment en les emissions, en els quals es modela el factor d'envelliment com un paràmetre sintonitzable, que permet variar des d'estats nous a envellits. Per altra banda, un model agrupat 0D _es desenvolupat per al DOC amb el propòsit d'estimar la relliscada de HC i CO, el qual és validat en un WLTC per a després ser usat en simulació. Per altra banda, un model 1D i un model 0D es desenvolupen per al SCR, els quals s'usen a continuació per a alimentar l'estratègia de diagnòstic i per a simulació. Finalment, les estratègies de diagnòstic es presenten per a la fallada total o retirada del DOC, així com per a l'estimació de l'eficiència en DOC i SCR. Per altra banda, la primera estratègia es divideix en passiva i activa, en la que s'utilitzen post-injeccions en la activa per a excitar el sistema i confirmar la fallada total si es dona el cas. A continuació, l'eficiència del DOC s'estima a través d'una tècnica indirecta en la que la temperatura d'activació es detecta i es relaciona amb l'increment d'emissions a través del model. Per altra banda, es desenvolupa un observador per a estimar l'estat d'envelliment del SCR, el qual està basat en un filtre de Kalman extés. No obstant això, per a evitar associar baixa eficiència degut a pobre qualitat de l'urea injectada a l'envelliment del SCR, un indicador de la qualitat de l'urea s'executa en paral·lel.[EN] This dissertation covers the development of algorithms oriented to improve the emission control system of Diesel engines. For this purpose, the inclusion of on-board sensors like temperature, NOx and NH3 sensors allows performing on-board diagnostics to the after-treatment systems focus of this work, which are the DOC and the SCR system. Then, the target is to meet on-board diagnostics regulations in order to keep emissions below a regulation threshold over time. Experimental tests, including gas analyzer measurements, allow having a wider view of the species in the exhaust line. Complementary, new and aged units are used in order to have the experimental effect of ageing on the catalysts. Then, the effect of temperature, exhaust mass flow, species concentrations and ageing is analyzed for DOC and SCR, in combination with the assessment of some relevant sensors measurements. As a result, the characteristics, opportunities and limitations extracted from experimental data are used as the basis for the development of models and diagnostics techniques. The assessment of temperature sensors measurements, along with the development of heat transfer models is required to feed temperature dependent functions. In this sense, the slow measurement of the DOC upstream temperature sensor is improved in transient conditions by means of a data fusion technique, based on a fast model and a Kalman filter. Then, a 1D and a 0D lumped heat transfer models are presented, in which the upstream inputs are assessed in relation to its use. On the other hand, a technique to estimate the temperature increase due to post-injection pulses oxidation is also presented. Both DOC and SCR models are proposed in order to estimate the effect of ageing on emissions, in which an ageing factor is modelled as a tunable parameter that allows varying from new to aged states. On the one hand, a 0D lumped model is developed for DOC in order to estimate the HC and CO species slip, which is validated in a WLTC and is then used for simulation. On the other hand, a 1D and a 0D models are developed for SCR, which are then used to feed the diagnostics strategy and for simulation. Finally, diagnostics strategies are presented for total failure or removal of DOC, as well as for efficiency estimation of DOC and SCR. On the one hand, the former strategy is separated into passive and active diagnostics, in which post-injections are used in active diagnostics in order to excite the system and confirm a total failure, in case. Then, the DOC efficiency estimation is done by means of an indirect technique in which the light-off temperature is detected and an emissions increase is related by means of the DOC ageing model. On the other hand, an observer to estimate the SCR ageing state is developed, which is based on an extended Kalman filter. However, in order to avoid associating low SCR efficiency to ageing, an indicator of the injected urea quality is developed to run in parallel.Mora Pérez, J. (2018). Control-oriented modelling and diagnostics of diesel after-treatment catalysts [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/115937TESI

Sensing, Actuation, and Embedded Control for a Custom SCR Nitrogen Oxides Emissions Reduction System

Diesel engines are the main power source for medium and heavy duty on road vehicles. With the rising standards for mileage of vehicles set by the Corporate Average Fuel Economy and the Environmental Protection Agency, diesel engines should soon be considered in lieu of gas engines. Despite advantages of diesel engines, diesel emissions include harmful gasses like carbon monoxide, nitrogen oxides and particulate matter. Selective Catalytic Reduction (SCR) systems have long been used to reduce diesel emissions from medium to heavy-duty diesel engines. Primary focus of this research effort is the implementation and improvement of a SCR system on light diesel engines. To improve efficiency we implemented a control law to limit the emissions within bounds ensuring low emissions for varied drive cycles. We developed a controller network using user datagram protocol to collect engine data using Arduino. The controller network establishes communication link between sensor data collection and a raspberry pi controller to enable full control over the test station

Experimental investigation of emission from a light duty diesel engine utilizing urea spray SCR system

Stringent pollutant regulations on diesel-powered vehicles have resulted in the development of new technologies to reduce emission of nitrogen oxides (NOx). The urea Selective Catalyst Reduction (SCR) system and Lean NOx Trap (LNT) have become the two promising solutions to this problem. Whilst the LNT results in a fuel penalty due to periodic regeneration, the SCR system with aqueous urea solution or ammonia gas reductants could provide a better solution with higher NOx reduction efficiency. This thesis describes an experimental investigation which has been designed for comparing the effect NOx abatement of a SCR system with AdBlue urea spray and ammonia gas at 5% and 4% concentration. For this study, a SCR exhaust system comprising of a diesel particulate filter (DPF), a diesel oxidation catalyst (DOC) and SCR catalysts was tested on a steady state, direct injection 1998 cc diesel engine. It featured an expansion can, nozzle and diffuser arrangement for a controlled flow profile for CFD model validation. Four different lengths of SCR catalyst were tested for a space velocity study. Chemiluminescence (CLD) based ammonia analysers have been used to provide high resolution NO, NO2 and NH3 measurements across the SCR exhaust system. By measuring at the exit of the SCR bricks, the NO and NO2 profiles within the bricks were found. Comparison of the measurements between spray and gas lead to insights of the behaviour of the droplets upstream and within the SCR bricks. From the analysis, it was deduced that around half to three quarters of the droplets from the urea spray remain unconverted at the entry of the first SCR brick. Approximately 200 ppm of potential ammonia was released from the urea spray in the first SCR brick to react with NOx. The analysis also shows between 10 to 100 ppm of potential ammonia survived through the first brick in droplet form for cases from NOx-matched spray input to excess spray. Measurements show NOx reduction was complete after the second SCR bricks. Experimental and CFD prediction showed breakthrough of all species for the short brick with gas injection due to the high space velocity. The long brick gas cases predictions gave reasonable agreement with experimental results. NO2 conversion efficiency was found higher than NO which contradicts with the fast SCR reaction kinetics. Transient response was observed in both cases during the NOx reduction, ammonia absorption and desorption process. From the transient analysis an estimate of the ammonia storage capacity of the bricks was derived. The amount of ammonia slippage was obtained through numerical integration of the ammonia slippage curve using an excel spreadsheet. Comparing the time constant for the spray and gas cases, showed a slightly faster time response from the gas for both NOx reduction and ammonia slippage

디젤 엔진에서 가상 질소산화물 센서에 관한 연구

학위논문 (박사)-- 서울대학교 대학원 : 기계항공공학부, 2013. 8. 민경덕.thus, this model can be applied to engines and after-treatment systems as a useful tool to control the engine-out NO without the use of a NOx sensor. In addition to being a virtual NO sensor, the estimation model can be applied to 1-D simulations, such as GT-SUITE and AMESIM, and demonstrate improved NO estimation results as the model is able to predict the NO level as same standard as the 3-D CFD simulation. Then, a newly developed NO estimation model was implemented on the embedded system bypassed from a conventional engine control unit for real-time estimation of NO during steady-states and transient engine operations. The results of the model were compared to real-time measurement of engine-out NO of a conventional Diesel engine at representative steady state operating points which cover the entire NEDC region. Also, EGR rate and main injection timing were varied to verify the predictability of the model under various conditions. The results showed that the model predicts steady state results well with R2 value of 0.96 for 76 HP-EGR cases. In addition, to verify transient estimation of NO, the engine-out NO was measured by a fast NO analyzer and compared with the results of the model during simple ramp transition conditions. Additionally, the engine-out NO emissions measured by a fast NOx analyzer and the estimated NO emissions were compared during ECE-15 and EUDC cycles. Furthermore, to extend the NO model to a complete NOx estimation model, an empirical NO2 estimation model was proposed based on the experiments under steady-state conditions. The in-house EGR estimation model was also applied in the NOx estimation model for accurate cycle-by-cycle estimation and used as an input during transient engine operations. This systematic research on the development of a virtual NOx sensor contributes to real-time NOx monitoring for transient NOx control and after-treatment system control.however, there were several limiting factors, such as complexity of the model for a real-time application, the necessity of various calibration constants, fitting processes for empirical equations and the demand for training for numerical models. In this study, to overcome the limits of previous studies, a real-time nitric oxide estimation model was developed based on the in-cylinder pressure and on data available from the ECU. As computational fluid dynamics can describe the process of NO formation which is not directly obtainable from experiments on a physical basis, the NO formation model was developed based on both the analysis of CFD results as well as on a physical model. Furthermore, the in-cylinder pressure is used to predict the amount of NO formation under various engine operating conditions as the pressure reflects the change in the combustion characteristics. The estimation model consisted of a simple calculation processTo meet the stringent emission regulations on diesel engines, engine-out emissions have been lowered by adapting new combustion concepts such as low-temperature combustion and after-treatment systems have also been used to reduce tailpipe emissions. To optimize the control of both in-cylinder combustion and the efficiency of an after treatment system to reduce NOx, the amount of real-time NOx emissions should be determined. Thus, many studies on a virtual NOx sensor using physical and phenomenological models have been reported. Previous studies have shown reliable NOx estimationstherefore, the model could predict the cycle-by-cycle NO in real-time. The validation results show that the model presented can predict engine-out NO well디젤 엔진에 대한 배기 규제가 강화됨에 따라 새로운 연소 기법을 이용하여 엔진 자체의 배출물을 줄이거나 후처리 장치 등을 이용하여 최종 배출물을 줄이는 등의 노력이 이루어지고 있다. 특히, 질소 산화물 (NOx) 감소를 위한 실린더 내 연소제어, 동시에 후처리 장치의 효율을 최적화하기 위해서는 실시간으로 배출되는NOx 배출량에 대한 정보가 필요하다. 따라서 물리적, 현상학적 모델을 사용한 가상 NOx 센서에 대한 많은 연구가 보고되고 있다. 기존 연구들은 비교적 정확하게 NOx 배출량을 예측하고 있지만 실시간 애플리케이션으로써 활용하기에는 현재 차량에 장착 중인 엔진 제어 장치의 계산 능력에 비해 모델이 너무 복잡하거나, 경험식을 피팅하기 위해 많은 보정 상수가 사용되고, 통계적 수학적 모델 등의 경우에는 많은 트레이닝이 필요한 등의 여러 가지 제한 요인이 있었다. 본 연구에서는 선행 연구의 한계를 극복하기 위해 실시간 실린더 압력과 ECU에서 얻을 수 있는 데이터에 기반한 실시간 NOx 예측 모델을 개발하였다. CFD 는 실험 과정에서 직접 얻을 수 없는 NO의 형성 과정을 자세히 설명 할 수 있기 때문에, 물리적 분석과 함께 CFD 결과의 분석을 통해 모델을 개발하였다. 또한 실린더 내 압력이 엔진 연소특성의 변화를 잘 반영하기 때문에, 다양한 엔진의 작동 조건에서 NO의 배출량을 예측할 수 있도록 연소압력이 사용되었다. 개발된 NO 예측 모델은 간단한 계산 과정으로 이루어졌기 때문에 실시간으로 사이클 별 NO를 예측할 수 있었다. 검증 결과는 제안된 모델이 엔진에서 배출되는 NO 를 잘 예측하는 것을 보여주었고, 따라서 개발된 모델이 NO센서 대용으로써 엔진과 후처리 장치의 제어를 위한 유용한 도구로써 시스템에 적용될 수 있음을 확인하였다. 가상 NO 센서로 사용될 수 있는 것 이외에도, 개발된 NO 예측 모델은 GT-SUITE와 AMESim 과 같은 1 차원 시뮬레이션에 적용되어CFD 모델과 동일한 수준으로 NO 수준을 예측할 수 있는 가능성을 가지고 있다. 이후, 개발 된 NO예측 모델은 정상 상태와 과도 엔진 작동 상태에서 NO의 실시간 추정을 위한 기존의 엔진 제어 장치를 우회한 임베디드 시스템에 구현되었다. 모델의 결과는 NEDC 전 영역을 커버하는 대표적인 정상 상태의 동작 점에서 엔진에서 배출되는 실시간 NO 측정값과 비교되었다. 또한 다양한 조건에서 모델의 예측성을 검증하기 위해 배기가스 재순환율과 주분사시기를 베이스 조건 대비 변화시켰다. 정상상태 검증 결과 HP-EGR 76 케이스에서 실험 결과와 R2=0.96 의 높은 예측 정도를 확인할 수 있었다. 또한 과도상태에서의 NO 예측 정도를 검증하기 위해 고속 NOx 분석기를 사용하여 엔진 속도, 부하 변경 등의 간단한 램프 조건에서 모델 결과와 비교하였다. 또한 유럽의 배출가스 측정 모드인 ECE-15 와 EUDC 사이클에서 고속 NOx 분석기 결과를 사용하여 모델을 검증하였다. 추가적으로, NO 만이 아닌 전체 NOx를 예측할 수 있도록 정상상태 실험 결과 기반의 경험식을 사용한 NO2 예측 모델을 제안하였다. 실시간 NOx 예측 모델에 정확한 과도상태 EGR 값을 제공하기 위해 실험실에서 개발된 EGR 예측 모델 또한 적용 되었다.Acknowledgements iii Abstract iv Contents vii List of Tables x List of Figures xi Acronym xiv Chapter 1. Introduction 1 1.1 Background and Motivation 1 1.1.1 Nitrogen oxides formation 1 1.1.2 The effect of nitrogen oxides on health and environment 2 1.1.3 Nitrogen oxides emission from diesel engines 3 1.1.4 Emission regulations for NOx from diesel engines 4 1.1.5 NOx reduction technologies and challenges in diesel engines 6 1.2 Literature Review on virtual NOx sensors 23 1.3 Objectives 28 Chapter 2. Development of NO estimation model with in-cylinder pressure measurement 29 2.1 Computational model and validation 30 2.1.1 Computational model for the CFD simulation 30 2.1.2 Validation of the computational models 30 2.2 NO estimation model 36 2.2.1 Basic assumptions for the NO estimation model 36 2.2.2 Physical model for NO formation 36 2.2.3 Determination of the duration of NO formation 39 2.2.4 Determination of averaged NO formation rate 39 2.2.5 Calculation of the maximum NO formation rate 40 2.2.6 Summary of the NO estimation model 43 2.3 Model validation with CFD results 53 Chapter 3. Experimental Apparatus 55 3.1 Engine setup 55 3.2 In-cylinder pressure measurement 61 3.3 EGR measurement 63 3.4 NO and NOx measurement 65 3.5 Real-time calculation of NO 68 Chapter 4. The effect of EGR rate on NO estimation model 72 4.1 Sensitivity analysis 72 4.2 Cylinder-to-cylinder measurement of EGR 74 4.3 EGR estimation model 76 Chapter 5. NO estimation during steady state and simple ramp transition using a real-time virtual NO sensor 82 5.1 Experimental cases 83 5.1.1 Steady state cases 83 5.1.2 Simple ramp transition cases 83 5.2 Experimental results 85 5.2.1 Steady state results 85 5.2.2 Simple ramp transition results 85 5.2.2.1 EGR rate change 85 5.2.2.2 Engine speed change 86 5.2.2.3 Simultaneous engine speed and load change 86 5.2.3 Source of error 86 5.2.4 Improvement of model accuracy using modified R and k 87 5.2.5 Cycle-by-cycle & cylinder-by-cylinder NO estimation 89 Chapter 6. NOx estimation during transient state using a real-time virtual NOx sensor 99 6.1 Extend to NOx (NO2) estimation model 100 6.2 Experimental conditions 105 6.3 Results and discussions 107 Chapter 7. Conclusion 113Docto

Dual-layered Multi-Objective Genetic Algorithms (D-MOGA): A Robust Solution for Modern Engine Development and Calibrations

Heavy-duty (HD) diesel engines are the primary propulsion systems used within the freight transportation sector and are subjected to stringent emissions regulations. The primary objective of this study is to develop a robust calibration technique for HD engine optimization in order to meet current and future regulated emissions standards during certification cycles and off-cycle vocation activities. Recently, California - Air Resources Board (C-ARB) has also shown interests in controlling off-cycle emissions from vehicles operating in California by funding projects such as the Ultra-Low NOx study by Sharp et. al [1]. Moreover, there is a major push for the complex real-world driving emissions testing protocol as the confirmatory and certification testing procedure in Europe and Asia through the United Nations - Economic Commission for Europe (UN-ECE) and International Organization for Standardization (ISO). This calls for more advanced and innovative approaches to optimize engine operation to meet the regulated certification levels.;A robust engine calibration technique was developed using dual-layered multi-objective genetic algorithms (D-MOGA) to determine necessary engine control parameter settings. The study focused on reducing fuel consumption and lowering oxides of nitrogen (NOx) emissions, while simultaneously increasing exhaust temperatures for thermal management of exhaust after-treatment system. The study also focused on using D-MOGA to develop a calibration routine that simultaneously calibrates engine control parameters for transient certification cycles and vocational drayage operation. Several objective functions and alternate selection techniques for D-MOGA were analyzed to improve the optimality of the D-MOGA results.;The Low-NOx calibration for the Federal Test Procedure (FTP) which was obtained using the simple desirability approach was validated in the engine dynamometer test cell over the FTP and near-dock test cycles. In addition, the 2010 emissions compliant calibration was baselined for performance and emissions over the FTP and custom developed low-load Near-Dock engine dynamometer test cycles. Performance and emissions of the baseline calibrations showed a 63% increase in engine-out brake-specific NOx emissions and a proportionate 77% decrease in engine-out soot emissions over the Near-Dock cycle as compared to the FTP cycle. Engine dynamometer validation results of the Low-NOx FTP cycle calibration developed using D-MOGA, showed a 17% increase brake-specific NOx emissions over the FTP cycle, compared to the baseline calibrations. However, a 50% decrease in engine-out soot emissions and substantial increase in exhaust temperature were observed with no penalties on fuel consumption.;The tools developed in this study can play a role in meeting current and future regulations as well as bridging the gap between emissions during certification and real-world engine operations and eventually could play a vital role in meeting the National Ambient Air Quality Standards (NAAQS) in areas such as the port of Los Angeles, California in the South Coast Air Basin

Automotive Powertrain Control — A Survey

This paper surveys recent and historical publications on automotive powertrain control. Control-oriented models of gasoline and diesel engines and their aftertreatment systems are reviewed, and challenging control problems for conventional engines, hybrid vehicles and fuel cell powertrains are discussed. Fundamentals are revisited and advancements are highlighted. A comprehensive list of references is provided.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72023/1/j.1934-6093.2006.tb00275.x.pd

Training Based Testing Of Temperature Sensors In Diesel Engine Aftertreatment System

The goal of this thesis is to research the possibility for creating an automated test for verifying the correct installation of temperature sensors in a diesel exhaust aftertreatment system. Both model and training based solutions are discussed. The implementation is done by training multiple machine learning models and comparing their results. Data was specifically collected for this research. Data collection consisted of taking measurements from a test engine using different sensor combinations. In total there were four different sensor combinations and for each combination 25 recordings were taken. The recordings had variating starting temperatures. The data was then labeled accordingly for supervised learning. Results show that classification of sensor installations can be achieved with high accuracy. All the used models provide promising results while logistic regression model seems perform the best. More important and limiting issue is the data gathering process for training and testing the models