Heavy-duty Application Research Articles

(Invited) Importance of Accelerated Stress Tests in Accelerated Discovery of Energy Materials

Accelerated Stress Tests (ASTs) are critical to the rapid discovery and deployment of new stable materials in electrochemical energy conversion technologies. The widespread use of validated ASTs can spur materials development efforts that address the key shortcomings of today’s materials. An excellent example of the use of ASTs has been in polymer electrolyte membrane fuel cells (PEMFCs). This talk will describe the various ASTs that have been utilized to evaluate oxygen reduction reaction (ORR) catalysts, catalyst supports and membranes in fuel cells. As better materials get developed, the ASTs have evolved over time to provide quick feedback on the degradation rates of these materials. Finally, the ASTs can also provide insights into the tradeoffs between cost, performance and durability of these electrochemical systems. Results from the Million Mile Fuel Cell Truck Consortium (M2FCT) will be presented with particular emphasis on heavy duty application of fuel cells. This talk will also address the ASTs that are currently under development for polymer electrolyte membrane water electrolyzers (PEMWEs). The Department of Energy (DOE) has recently set performance and durability targets for PEMWEs. The Hydrogen from Next generation Electrolyzers of Water (H2NEW) consortium is currently engaged in developing ASTs for PEMWEs and these results will be presented and discussed. By providing these two specific examples, the importance of ASTs in materials discovery will be highlighted. Acknowledgement: This work was supported by the Hydrogen and Fuel Cell Technologies Office (HFTO), Office of Energy Efficiency and Renewable Energy, US Department of Energy (DOE). Funding is through the Million Mile Fuel Cell Truck (M2FCT) consortia, technology managers G. Kleen and D. Papageorgopoulos and Hydrogen from Next generation of Electrolyzers of Water (H2NEW) consortia, technology manager Dave Peterson.REFERENCES: https://www.energy.gov/eere/fuelcells/technical-targets-proton-exchange-membrane-electrolysis

(Invited) Membrane Degradation in Polymer Electrolyte Membrane Fuel Cells for Heavy Duty Applications

Polymer electrolyte membrane fuel cells (PEMFCs) are being considered for heavy duty applications, and the DOE has established various performance and durability targets to enable their adoption.1. The key differences between light and heavy-duty application of fuel cells is their increased durability and operating efficiency requirements for heavy duty applications when compared to the lower cost requirement for light duty applications. While higher catalyst loadings can be utilized to increase the fuel cell performance and catalyst lifetime, membrane durability could be a significant outstanding challenge. Membranes are expected to last 25,000 hours to 30,000 hours for heavy duty applications and the Million Mile Fuel Cell Truck Consortium (M2FCT) is evaluating various membrane technologies for use in heavy duty drive cycles. Current state of the art membranes with both mechanical and chemical stabilization have already met light-duty durability requirement of 5000+ hours and have the potential to meet 25,000+ hour lifetimes. This talk will describe the various membrane related accelerated stress tests (ASTs) developed by the consortium and will present membrane durability results obtained from long-term (500 hours) fuel cell operation at elevated temperature (90 oC). Both the mechanical and chemical durability of membranes will be discussed with particular emphasis and fluoride emission rates (FERs) and lifetime predictions. Acknowledgement: This work was supported by the Hydrogen and Fuel Cell Technologies Office (HFTO), Office of Energy Efficiency and Renewable Energy, US Department of Energy (DOE) through the Million Mile Fuel Cell Truck (M2FCT) consortia, technology managers G. Kleen and D. Papageorgopoulos.

Analysis of the Vibrational Behavior of dual-fuel RCCI combustion in a Heavy-Duty Compression Ignited Engine fueled with Diesel-NG at Low Load

In the field of internal combustion engines, the Low Temperature Combustions (LTC) appear to have the potential to reduce the formation of both soot and nitrogen oxides. One of the most promising LTC is Reactivity Controlled Compression Ignition (RCCI) which is based on the combustion of a lean low reactivity fuel-air mixture generated in the intake manifold and autoignited by small injections of high reactivity fuel introduced at high pressure in the combustion chamber. By the combination of net-zero natural gas and biodiesel, such LTC methodology might represent a suitable solution moving toward zero-emissions in transportation sector.Despite the potential to reduce pollutant emissions, Low Temperature Combustion strategies face a challenge in controlling the angular position where the combustion takes place which can be overcome by a proper management of the high-pressure injections.One potentially interesting application is related to trucks, mainly because they have long periods of idling, since emissions can be drastically reduced by means LTC. A single cylinder research engine for heavy duty application is operated under steady state conditions at low load and speed to analyze the possibility of controlling the engine behavior in dual fuel RCCI mode. The results indicate that the combustion mode switches from the dual-stage to gaussian within a narrow angular range. A further advance of the start of injection can generate misfires and significant variations in typical combustion indexes, while a delayed start of injection can cause impulsive combustion that rises the cylinder temperature and results in high-frequency pressure oscillations inside the combustion chamber. These oscillations are related to the combustion chamber typical resonance frequency, and if relevant in amplitude and persist for a long time, they might generate a potential source of failures.

Porous Carbon Fiber Flow Fields for Heavy-Duty Polymer Electrolyte Fuel Cell (PEFC) Applications

The US Department of Energy (DOE) interim (2030) targets for polymer electrolyte fuel cells (PEFCs) in heavy duty vehicle applications accentuate reduced system cost (US $80/kW), increased peak efficiency (68%), and longer system lifetime (25,000 hrs) [1]. The bipolar plate in a PEFC has to serve several functions such as uniform reactant distribution with minimum pressure loss, efficient product water removal, and maintain high electronic and thermal conductivity. Multiple studies [e.g., 2-4] describe novel materials and engineered designs potentially meet these performance and durability requirements; however, cost is the limiting factor in most cases. For example, the cost of a state-of-the art stainless steel (SS 316L) plate, already approaching minimum feasible plate thickness, is estimated to be (US $3.5/kWnet), which is 17% higher than current DOE target [1]. Thus, low-cost substrate alternatives are required to reduce the cost and facilitate commercialization in heavy-duty applications. One such alternative is a novel PEFC architecture [5] utilizing a laminated structure consisting of flat thin metal foils that separate flow fields with channels formed into the porous gas diffusion layer (GDL). This architecture enables the use of much thinner metal plates compared to stamped ones, reducing the overall system mass and cost. The current study explores the performance of a wide aspect ratio (200 mm x 30 mm) PEFC test fixture with porous carbon fiber flow field compared to conventional solid flow field over a wide range of operating conditions. The wide aspect ratio and channel/rib dimensions for both the porous and the conventional solid flow field are chosen to provide a reasonable pressure loss relevant to heavy-duty PEFC stack application. This new architecture is expected to enable comparable system performance while reducing plate weight and cost.

Effect of differential control and sizing on multi-FCS architectures for heavy-duty fuel cell vehicles

The current trend towards a zero-emission transport sector has increased the interest of the scientific community and the industry in fuel cell (FC) technologies in the past few years. Previous studies have focused on passenger car analyses to differentiate them from the current battery electric vehicle (BEV) alternative. However, deploying these technologies may be even more critical for the transportation-produced global emissions if they are used in different applications, such as heavy-duty commercial vehicles. This study uses a differential control strategy to find the best fuel-cell performance for a heavy-duty vehicle application. In addition, and as a differentiation point from other studies in the literature, this article exploits the modularity of the heavy-duty truck sector to implement a design with optimal fuel cell system (FCS) sizing and control dynamics distribution in terms of durability and H2 consumption. Low dynamics could increase 471% in durability just for a 3.8% increase in H2 consumption. When using a multi-FCS with non-equal power FCS, a high dynamics behavior of the small FCS significantly improves the durability for a small consumption penalty (less than 0.7%). The obtained data has proven that the combination of these two design strategies shows an improved vehicle performance that could lead to environmental impact and cost reduction, which is significant in the current development stage of fuel cell vehicle (FCV) technologies.

Numerical Validation and Optical Study of Injection of Different Oxymethylene Ether Fuels for Heavy-Duty Application

<div>A reliable toolchain for the validation and evaluation of numerical spray break-up simulation for the potentially carbon-neutral fuels polyoxymethylene dimethylether (POMDME, or short OME) is developed and presented. The numerical investigation is based on three-dimensional computational fluid dynamics (3D-CFD) with the commercial code STAR-CD v2019.1 using a Reynolds-averaged Navier-Stokes (RANS) equations approach. Fuel properties of the representatives OME<sub>1</sub> and OME<sub>3</sub> are implemented into the software and with that the fuels are investigated numerically.</div> <div>For validation purposes, optical experimental results in a heated spray chamber with inert nitrogen-pressurized atmosphere are presented. The measurement data are based on Mie scattering of the liquid phase and Schlieren imaging of the vapor phase. Solely experimental results are shown for OME<sub>1b</sub> and OME<sub>3–6</sub> to assess if the knowledge from the numerical modeling with OME<sub>1</sub> and OME<sub>3</sub> can also be transferred to the corresponding multicomponent fuels. While the results for a match between OME<sub>3</sub> and OME<sub>3–6</sub> are close, the measurement for OME<sub>1b</sub> exceeds the result of OME<sub>1</sub> in the liquid penetration significantly. This is explained by the molecular structure of the low-volatile additive in OME<sub>1b</sub> based on long-chained polyglycol ethers. For the numerically modeled operating conditions, the fuel injection rate with the corresponding fuel is measured. Two atomization and spray break-up approaches are investigated in simulation, based on Reitz-Diwakar (RD) models and a combination using Huh’s atomization and the Kelvin-Helmholtz Rayleigh-Taylor (KHRT) spray break-up models. A holistic parameter study in a single operating point with the fuel OME<sub>1</sub> helps to determine the sensitivities of the models. Adjustments to the spray momentum by a variation of the parameter for the nozzle hole diameter are used to get results closely aligned with measurement data. The transfer of the calibrated RD model to a validation study with OME<sub>3</sub> at different operating conditions matches well to measurement with no further adjustments necessary.</div>

Sensorless force estimation on fingertip with gravitational compensation for heavy-duty pneumatic tri-grasper robot

The paper presents the proposed sensorless force estimator design for pneumatic robot fingertip by using gravitational compensation and pressure changed in pneumatic cylinder piston. The approach is done to replace the commercial force sensor that may be expensive for heavy-duty configuration. The formulation was done by considering the torque of robot's finger joint, finger dimension as well as its actuator and the different pressures in cylinder piston. The gravitational force is calculated from the geometry of the robot's finger as dynamic gain for the force of pneumatic cylinder. The proposed method is validated on a heay-duty pneumatic Tri-grasper Robot with the simple basic movement and blocked randomly by human barehand. The results show that the force output by the estimator is almost identical to the loadcell sensor that attached on the fingertip at about 2% error in average. The sensitivity is a bit low for small and fragile material but enough for heavy-duty application that generally with hard and rough surfaces.

Operando X-Ray Absorption Spectroscopy of Pt Catalyst in Polymer Electrolyte Fuel Cell Under High Temperature and Low Humidification

For the widespread use of fuel cell vehicles, it is necessary to improve the performance and durability of the cathode catalyst of polymer electrolyte fuel cells (PEFCs). In particular, high-temperature operation of PEFCs is attracting attention for application to commercial vehicles for heavy-duty application. Operation at higher temperatures than the conventional one (60-80°C) is expected to enhance oxygen reduction kinetics and mass transfer and reduce specific adsorption of ionomers. Despite such advantages, due to the thermal effect, the oxide formation on Pt surface is expected to be enhanced and decrease the activity of the catalyst. However, the quantitative relationship between catalyst behavior and the electronic structure of Pt under high temperature operation has not yet been elucidated. Here, we developed an MEA cell for high temperature and high pressure conditions and analyzed the oxidation state and local structure of Pt on Pt/C catalysts at different temperatures by operando XAS measurements.MEAs were prepared with Pd/C as anode catalyst, Pt/C as cathode catalyst. XAS measurements of the Pt LIII absorption edge were made at 80°C, 105°C, and 120°C with 100% H2 flowing to the anode and Air flowing to the cathode, and spectra were collected by the transmission mode. The area values of the XANES spectra were calculated to compare the relationship of Pt oxide formation with operating temperature and the local structural model of Pt oxide at high temperature by EXAFS.Comparison of operando XANES results of cathode catalyst Pt/C under conventional operating temperature (80°C), 105°C, and 120°C showed a marked difference, especially at 80°C and 120°C. In addition, the XANES area values increased as the operating temperature was increased. This is thought to be due to the fact that Pt oxide formation is accelerated at higher temperatures. Next, comparing the EXAFS analysis results at each temperature, the Pt-O bond peak is stronger at 120°C, indicating that Pt oxidation is more advanced than at 80°C. The 120°C results can be explained by a mixed model of β-PtO2 and Pt metal. Pt-O bond coordination number analysis shows that β-PtO2, in which oxygen is latent inside Pt, is formed more frequently at high temperatures. From this result, it was found that the structure of Pt oxide is different in high-temperature systems, and that catalyst design must take this into account. Fig ure 1. Pt LIII-edge XANES spectra Area vs. Applied voltage for pure H2 at the cathode of Pt/C. MEA temperature: blue circle is 80°C, black circle is 105°C, red circle is 120°C. Fig ure 2. Pt LIII-edge EXAFS Pt-O bond coordination Number vs. Applied voltage for pure H2 at the cathode of Pt/C. MEA temperature: blue triangle is 80°C, black triangle is 105°C, red triangle is 120°C. Acknowledgement This work was supported by a NEDO FC-Platform project commissioned by the New Energy and Industrial Technology Development Organization (NEDO) Reference s : [1] Hideto I.; Koichi I.; Masashi M.; Yoshimi K.; Kazuo K.; Yasuhiko I., J . Am . Chem . Soc ., 2009, 131 (17), 6293-6300. Figure 1

Impacts of Limestone Exploitation on the Socio-economic Development of Okpella, Nigeria

Limestone and other solid minerals exploitation have been a major activity at Okpella and its environs. This has tremendously contributed to the economic development of the host community, and on the other side poses a great danger to the health and the well-being of Okpella due to the continuous release of carbon emission, suspended particulate matter, and defying noise pollution from the mining and hauling equipment. However, long extraction of limestone has been attributed to land degradation as responded by 43.6% of the sampled population, whereas 19.2%, 14.6%, and 12.7% agreed to the use of heavy-duty equipment, land clearing, tailing dams, and application of toxic materials as responsible for land degradation and devaluation. Conversely, 39.4% of the respondents indicated that the exploration of limestone and other solid minerals could be attributed to cough, 22.5% to catarrh, and 13.2% to malaria. In conclusion, it is obvious that limestone exploration is beneficial to the socio-economic development of the host community but detrimental to their human and environmental health.

Fuzzy Algorithms for Diagnosis of Furnace Transformer Insulation Condition

Implementation of the smart transformer concept is critical for the deployment of IIoT-based smart grids. Top manufacturers of power electrics develop and adopt online monitoring systems. Such systems become part of high-voltage grid and unit transformers. However, furnace transformers are a broad category that this change does not affect yet. At the same time, adoption of diagnostic systems for furnace transformers is relevant because they are a heavy-duty application with no redundancy. Creating any such system requires a well-founded mathematical analysis of the facility’s condition, carefully selected diagnostic parameters, and setpoints thereof, which serve as the condition categories. The goal hereof was to create an expert system to detect insulation breach and its expansion as well as to evaluate the risk it poses to the system; the core mechanism is mathematical processing of trends in partial discharge (PD). We ran tests on a 26-MVA transformer installed on a ladle furnace at a steelworks facility. The transformer is equipped with a versatile condition monitoring system that continually measures apparent charge and PD intensity. The objective is to identify the condition of the transformer and label it with one of the generally recognized categories: Normal, Poor, Critical. The contribution of this paper consists of the first ever validation of a single generalized metric that describes the condition of transformer insulation based on the online monitoring of the PD parameters. Fuzzy logic algorithms are used in mathematical processing. The proposal is to generalize the set of diagnostic variables to a single deterministic parameter: insulation state indicator. The paper provides an example of calculating it from the apparent charge and PD power readings. To measure the indicativeness of individual parameters for predicting further development of a defect, the authors developed a method for testing the diagnostic sensitivity of these parameters to changes in the condition. The method was tested using trends in readings sampled whilst the status was degrading from Normal to Critical. The paper also shows a practical example of defect localization. The recommendation is to broadly use the method in expert systems for high-voltage equipment monitoring.

Waste Material via Geopolymerization for Heavy-Duty Application: A Review.

Due to the extraordinary properties for heavy-duty applications, there has been a great deal of interest in the utilization of waste material via geopolymerization technology. There are various advantages offered by this geopolymer-based material, such as excellent stability, exceptional impermeability, self-refluxing ability, resistant thermal energy from explosive detonation, and excellent mechanical performance. An overview of the work with the details of key factors affecting the heavy-duty performance of geopolymer-based material such as type of binder, alkali agent dosage, mixing design, and curing condition are reviewed in this paper. Interestingly, the review exhibited that different types of waste material containing a large number of chemical elements had an impact on mechanical performance in military, civil engineering, and road application. Finally, this work suggests some future research directions for the the remarkable of waste material through geopolymerization to be employed in heavy-duty application.

48V EGR Pump System Development and Fuel Benefit Evaluation

Upcoming global emission regulations include considerable reduction in emission of nitrogen oxides (NOx) and greenhouse gases (GHGs) for vehicles with heavy-duty (HD) diesel application. These regulations will phase between 2024 and 2030 in the United States and the European Union. CARB Regulations include up to 90% reduction in NOx levels along with ∼25% reduction in CO2. One of the primary technologies used to reduce engine out NOx emission is the use of cooled exhaust gas recirculation (EGR). Research studies carried out across multiple domains by engine/vehicle original equipment manufacturers (OEMs) and others have identified air handling as one of the technologies to help meet next-generation regulations (Joshi, 2020; Dreisbach et al. 2021). This includes more efficient turbomachinery which helps improve engine efficiency and thus reduce GHGs. This has an adverse effect on driving EGR which affects engine out NOx. In this study, the development and performance impact of the EGR pump is investigated, which allows improved engine fuel efficiency without the corresponding penalty to engine out NOx. Computational fluid dynamics (CFD) is used to optimize the EGR pump design, which leads to reduction in fluid-borne noise of the pump, which is then evaluated for fuel benefits using a calibrated GT-POWER engine model.

Evaluation of High-Temperature Martensitic Steels for Heavy-Duty Diesel Piston Applications

<div class="section abstract"><div class="htmlview paragraph">Five different commercially available high-temperature martensitic steels were evaluated for use in a heavy-duty diesel engine piston application and compared to existing piston alloys 4140 and microalloyed steel 38MnSiVS5 (MAS). Finite element analyses (FEA) were performed to predict the temperature and stress distributions for severe engine operating conditions of interest, and thus aid in the selection of the candidate steels. Complementary material testing was conducted to evaluate the properties relevant to the material performance in a piston. The elevated temperature strength, strength evolution during thermal aging, and thermal property data were used as inputs into the FEA piston models. Additionally, the long-term oxidation performance was assessed relative to the predicted maximum operating temperature for each material using coupon samples in a controlled-atmosphere cyclic-oxidation test rig. A current commercial steel piston alloy, quenched and tempered martensitic steel 4140, was tested in a single-cylinder research engine for a baseline oxidation and mechanical performance assessment using an abbreviated (50h) durability test plan. The predicted suitability of a candidate piston material in an engine is primarily based on its elevated temperature strength, oxidation resistance, and the complex influence of thermal conductivity, the latter of which is substantially lower for the candidate materials considered in this research relative to the traditional alloys. Although the lower thermal conductivity causes the candidate alloys to operate in higher temperature ranges under identical engine operating conditions and piston geometries, increasing the likelihood of partially or completely negating their strength and oxidation resistance advantages relative to 4140 and MAS steels, this evaluation indicates that several of the candidate piston alloys are predicted to enable improved oxidation resistance under more severe engine operating conditions relative to the current piston materials. However, further evaluation is required to determine if the elevated temperature fatigue strength and durability of these alloys are suitable for more severe engine conditions.</div></div>

Theoretical and finite element analysis (FEA) of coated composite leaf spring for heavy-duty truck application

There is always increase in demand of extended application of automobile parts due to long spanning life, weight reduction and high performance. Conventional steel leaf is lagging behind in automobile industries due to replacement by composite materials as a result of weight reduction and excellent mechanical properties. The research aim is to compare the theoretical and finite element analysis of coated composite materials for heavy duty application by giving enhanced von misses stress and better deflection. CATIAVR9 and ANSYS software were both used for the model and the numerical analyses of both the coated composite materials and the conventional steel leaf.Weight reduction and strength enhancement were experienced by composite leaf spring with E-glass/epoxy showing 7.95% weight reduction, carbon epoxy 8.50%, bamboo polyester 8.8% and graphite epoxy 8.5%. when compared with conventional steel leaf spring. Maximum displacement shown by E-glass/epoxy was 0.65088 mm, graphite epoxy with displacement of 0.66416 mm, carbon epoxy with displacement of 0.6677 mm and bamboo polyester displacement with 0.67647 mm when the composite leaf springs were coated with molybdenum. The conventional leaf spring showed von mises stress of 508.33 MPa via the static analysis results. While von mises stresses shown by the composite materials were 459.16 MPa for bamboo polyester, 423.3 MPa for graphite epoxy, 463.5 MPa for carbon epoxy and the lowest stress of 406.6 MPa came from E-glass/epoxy material. Lower stresses and displacements were shown by composite leaf springs four models as compared to conventional steel leaf spring. With coated composite leaf spring, weight reduction of 5.55% was shown for bamboo polyester, carbon epoxy with 4.97%, graphite epoxy with 4.87 wt reduction and E-glass/epoxy with 4.585% weight reduction.

Feasibility assessment of hydrogen-rich syngas spark-ignition engine for heavy-duty long-distance vehicle application

The feasibility of syngas-fueled engine was assessed in numerical simulation using the single-cylinder engine experiment and on-road driving data. A 6-cylinder, 1841-cm3, spark-ignition engine was designed for a highway express bus in South Korea. Firstly, a one-dimensional engine model was constructed on a basis of the single-cylinder engine experimental data. The valve timings were optimized for maximizing the intake air flow at each engine speed. Then, the vehicle simulation model was built for the highway express bus equipped with the syngas engine and 10-speed automatic transmission. A parametric investigation was performed to optimize the gear shift schedule for the best fuel economy under on-road driving condition. The driving data was acquired from an actual highway express bus traveled from Daejeon to Seoul in South Korea. The syngas engine bus exhibited the trip fuel economy of 412 g/km in the driving simulation. The estimated travel distance was 194 km using the stock fuel tank employed for 20-MPa compressed natural gas.

Challenges Overwhelmed to Meet BSVI Emissions with SPFI Fuel System for Heavy-Duty CNG Engine Application

<div class="section abstract"><div class="htmlview paragraph">As competent and low-pollution alternative fuel, CNG has revealed its excellence over engine performance and emissions. In recent years, CNG is considered as the diesel engine alternative fuel for heavy-duty engine applications due to its lower emissions and cost effective after-treatment systems. Due to the implementation of stricter emission norms over the years, the evolution of the fuel supply system has become more robust and electronically controlled.</div><div class="htmlview paragraph">In the case of CNG engines, most of the engines were equipped with MPFI fuel system, for its precise fuel control abilities and controlling emission parameters. However, this MPFI system encompasses severe design changes in the intake manifold and is cost worthy to OEMs over the SPFI fuel system. MPFI system adds on the overall cost of the engine unit and its maintenance when compared to SPFI system. SPFI fuel system had proved its robustness to achieve BSIV emission norms but, due to challenging test methods and stringent emission limits, BSVI development with this fuel system seems cumbersome with limited control parameters. This paper presents the research work conducted on a heavy-duty CNG engine with a SPFI fuel system. The challenges involved for achieving the BSVI emissions through engine calibration, without major engine hardware change along with engine performance is incorporated in this work.</div></div>

Ultra-Low NOx Emissions with a Close-Coupled Emission Control System on a Heavy-Duty Truck Application

<div class="section abstract"><div class="htmlview paragraph">Heavy-duty vehicles represent a significant portion of road transport and they need to operate in a clean and efficient manner. Their emission control systems need to be enhanced to sustain the high conversion efficiencies seen during motorway conditions inother operating conditions. The European Commission is developing legislative proposals for Euro 7 emissions regulations for light- and heavy-duty vehicles. The new Euro 7regulation will likely focus on ensuring the emissions from heavy-duty vehicles are minimized over extensive on-road operating conditions and specifically on operating conditions such as urban driving and cold-start operation. These challenges are increased by the need to ensure low secondary emissions like NH<sub>3</sub> and N<sub>2</sub>O, as well as a low impact on CO<sub>2</sub> emissions. The paper outlines the low pollutant emissions achieved by a heavy-duty Diesel demonstrator vehicle. The vehicle is equipped with an innovative layout of state-of-the-art emission control technologies, combined with an advanced controlstrategy on an existing Euro VI long-haul truck. The new emissions control system integrates a close-coupled DOC, a catalyzed DPF, dual-SCR system -one in a close-coupled position-, with twin AdBlue® dosing controlled withFEV developed software. Both SCR catalysts contain an ammonia slip catalyst. The innovative system layout allows ultra-low NOx emissions and well controlled secondary emissions in even the most challenging conditions with minimal impact on CO<sub>2</sub> emissions. Pollutant emissions were evaluated over a broad range of operating conditions, including different payloads to show the emissions reduction potential. This paper also includes results obtained from the on-road Portable Emissions Measurement System (PEMS) testing.</div></div>

Advanced Design and Optimal Sizing of Hydrostatic Transmission Systems

This paper presents a novel method for designing and sizing high-efficient hydrostatic transmissions (HTs) for heavy duty propulsion applications such as agricultural and construction machinery. The proposed method consists in providing cost effective HT architectures that maximizes efficiency at the most frequent operating conditions of the transmission, as opposed to the traditional HT design methods based on the most demanding requirements of the system. The sizing method is based on a genetic optimization algorithm for calculating the optimal displacement of the main units of the HT to maximizes the efficiency in the most frequent operating conditions of the vehicle. A simulation model for HTs is built in MATLAB/Simulink® environment to test three different circuit alternatives for basic HTs. Considering a particular 250 kW heavy-duty application for which drive cycle data were available, this study shows great improvement in energy efficiency (14%) and power saving (20.1%) at frequent operating conditions while still achieving the corner power condition.

Improving performance specifications of internal combustion engine dedicated to plug-in hybrid electric vehicles based on coupled optimization methodology

In the context of heavy-duty application, this paper introduces a novel methodology for better defining the specifications of the internal combustion engine (ICE) in plug-in hybrid electric vehicles (pHEVs) with energy management-based evaluation. From mathematical modelling of reference engine static efficiency and maximum torque, parametric transformations are performed to explore alternative engine designs. A coupled optimization problem is formulated as a bi-level form with powertrain optimal energy management based on a combinatorial problem formulation solved by Branch&Bound algorithm in the inner loop and exhaustive evaluation of ICE designs in the outer loop. A detailed transmission losses model and limitations on engine torque response dynamics are included in the optimization problem. The number of engine ignition and shutdown phases are also considered in order to better simulate the powertrain. The results show potential fuel reduction of 2.4% on a regional delivery cycle with zero-emission zones, and are intended to be used as specifications to guide further detailed engine development dedicated to hybrid powertrains.

Effect of 6 Wt.% Particle (B4C + SiC) Reinforcement on Mechanical Properties of AA6061 Aluminum Hybrid MMC

Aluminum based hybrid metal matrix composite with more than two particle reinforcement is very much popular for heavy duty application, and the proportion of these particle reinforcement can be controlled to achieve desired mechanical properties (strength and wear resistance). AA 6061 alloys popularly used in aircraft and automobile applications, tends to have inferior tribological property and therefore particle reinforcements are being made to strengthen the matrix. The prime objective of this investigation is to study the effect of varying wt.% of proportionate individual reinforcement (SiC and B4C) on the mechanical properties of a particular composition (6 wt.%) of AA 6061 hybrid composite. The present investigation is done to evaluate the dependance of hard particle reinforcements on the strength and elongation behaviour of hybrid composite. Hardness measurement and uniaxial loading techniques were used to characterize the mechanical properties of the as-cast hybrid composites, whereas OM, XRD and SEM analysis was done to study the distribution of reinforcement within the base (AA 6061) metal matrix phase. The improvement in mechanical properties, such as Vickers hardness, UTS, yield strength and elongation were presented and explained using various hypothesis proposed by previous studies. The role of clustering theory and effect of binary eutectic Mg2Si phase found to be key the enhanced mechanical properties of the hybrid composites. Addition of Alkaline Earth Metal (Mg) during the synthesis process have led to an increase in the elongation of hybrid composite with the increase in wt.% of reinforcement which is analogous to the effect of alkali metals (‘Na’ and ‘Li’) addition that helps in refining the Mg2Si Eutectic phase.