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Newly designed gears are subject to higher loads that demand a steel that is capable of greater pitting resistance. The application of shot peening to gears has been increasing to improve tooth root strength, but pitting resistance had not been necessarily high. This study examines the effect of alloying additions mainly on tempering resistance and the formation of a non-martensitic layer. The developed high Si-Mo type steel shows excellent pitting resistance, even in shot peened gears, as compared to that of conventional steels due to high tempering resistance and the thin, uniform non-martensitic layer. This new steel is of practical use in some multi-speed automatic transmission gears.

This paper introduces a novel design of an internal combustion engine heat transfer model within a comprehensive simulation environment. The modelling is based on a lumped mass parameters approach. The paper discusses an approach for a heat transfer model, implemented in MATLAB/SIMULINK, the coupling process and the physical interface. The methodology of implementing this model in a comprehensive simulation environment is presented. The calculation of the combustion process and the inner circuits for the water and oil loops, considered as boundary conditions for the Heat Transfer Model are performed using the 1D engine cycle simulation program BOOST i.e. the 1D cooling simulation program KULI. This results in a scalable and modular structure of the model, which in turn permits a flexible design of different engine types. In order to carry out a comprehensive thermal calculation, a coupled simulation with these three different models is performed.

Two soot-containing turbulent non-premixed flames burning gaseous acetylene in atmospheric-pressure air were investigated by conducting non-intrusive optical experiments at various flame locations. The differences in burner exit Reynolds numbers of these flames were large enough to examine the influence of flow dynamics on soot formation and evolution processes in heavily-sooting flames. By accounting for the fractal nature of aggregated primary particles (spherules), the proper interpretation of the laser scattering and extinction measurements yielded all the soot parameters of principal interest. With the separation of spherule and aggregate sizes, the axial zones of the prevailing turbulent soot mechanisms were accurately identified. With the high propensity of acetylene fuel to soot, relatively fast particle nucleation process led to high concentrations immediately above the burner exit.

Changing and more stringent emissions norms and fuel economy requirements often call for modifications in the fuel injection system of a Diesel engine. There exists a strong interaction between the injection system hydraulics and the dynamics of mechanical components within the unit injector and the camshaft-driven mechanical system used to pressurize it. Hence, accurate predictive analysis of design issues or evaluation of design changes requires highly coupled and integrated hydro-mechanical simulations, combining analysis of fuel injection hydraulics and the dynamics of all mechanical parts, including the cam-drive system. This paper presents an application of such an integrated model to the study and alleviation of an observed increase in mechanical vibration and related noise levels associated with a proposed design change in unit injectors and valve-train of a 6-cylinder truck diesel engine.

Study and modeling of transient operation is an important scientific objective. This is due to the fact that the majority of daily vehicle driving conditions involve transient operation, with non-linear situations experienced during engine transients. Thus, proper interconnection is needed between engine, governor, fuel pump, turbocharger and load. This paper surveys the publications available in the open literature concerning diesel engine simulations under transient operating conditions. Only those models that include both full engine thermodynamic calculations and dynamic powertrain modeling are taken into account, excluding those that focus on control design and optimization. Most of the attention is concentrated to the simulations that follow the filling and emptying modeling approach. A historical overview is given covering, in more detail, research groups with continuous and consistent study of transient operation.

Sodium borohydride hydrogen storage systems offer great promise in meeting the challenges of hydrogen storage for automotive applications. The physical processes inside a NaBH4 packed-bed reactor are complicated, involving multi-component, multi-phase, multi-mode heat and mass transfer. All of these processes are closely coupled with chemical reaction kinetics. To design and optimize the reactor, a detailed reactor model is needed. This study addressed this problem using a one-dimensional homogeneous model. The diffusion coefficient inside the catalyst and the water vapor mass transfer coefficient were obtained by fitting experimental data at a moderate flow rate and were used to predict reactor behaviors at other flow rates. The predicted temperature, conversion and relative humidity profiles match experimental data well although the pressure drops are underpredicted.

In this paper a fast DPF screening procedure is proposed using small-scale filter samples of different technologies in a well-controlled environment but under realistic engine exhaust conditions. The DPF samples are evaluated in a specially built Multi-Reactor Assembly (MRA) with respect to their flow resistance, filtration efficiency, soot loading behavior, soot oxidation behavior, as well as their ash induced ageing behavior.

Autoignition of a homogeneous mixture is very sensitive to operating conditions, therefore fast control is necessary for reliable operation. There exists several means to control the combustion phasing of an Homogeneous Charge Compression Ignition (HCCI) engine, but most of the presented controlled HCCI result has been performed with single-input single-output controllers. In order to fully operate an HCCI engine several output variables need to be controlled simultaneously, for example, load, combustion phasing, cylinder pressure and emissions. As these output variables have an effect on each other, the controller should be of a structure which includes the cross-couplings between the output variables. A Model Predictive Control (MPC) controller is proposed as a solution to the problem of load-torque control with simultaneous minimization of the fuel consumption and emissions, while satisfying the constraints on cylinder pressure.

Widespread implementation of homogeneous charge compression ignition (HCCI) engines is presently hindered by stability, control, and load range issues. Although the operable HCCI speed/load range is expanding, it is likely that the initial HCCI engines will rely on conventional combustion for part of the operating cycle. In the present study, we have investigated the role of fuel properties and chemistry on the operation of a spark-assisted gasoline HCCI engine. The engine employed is a single cylinder, 500 cc, port fuel injected research engine, operating near lambda = 1.0 and equipped with hydraulic variable valve actuation. HCCI is initiated by early exhaust valve closing to retain exhaust in the cylinder, thereby increasing the cylinder gas temperature. This is also referred to as a ‘negative overlap’ strategy.

Early direct injection with HCCI like properties is characterized by the presence of an ignition dwell - the interval between end of fuel injection and start of combustion, during which fuel-air mixing occurs. Previous work by Jhavar and Rutland (2005) has focused on investigating different methods to affect fuel-air mixing during the ignition dwell. That study helped to evaluate the relative influence of various mixing control strategies to achieve ignition control. In this study, we attempt to look into the mixture preparation process in more detail. Therefore, turbulence is studied using Large Eddy Simulation (LES) models in place of Reynolds Averaged Navier Stokes (RANS) models. While LES is computationally more expensive than RANS, it depicts the flow structure more accurately. Therefore, it can be applied to engines in order to gain a better representation of local mixing as well as accurately simulate unsteady flow behavior in engines.

The tightening of diesel emissions legislation throughout the EU and US is leading to the development of emission control devices to enable diesel engines to meet the standards. One system which has shown great promise in controlling PM emissions is Diesel Particulate Filter (DPF). Even DPF has showed good filtering efficiency, it has also lots of challenge for serial applications. One of the challenges is regeneration of filtered PM at urban driving condition. Since the temperatures are much lower than those of PM oxidation by itself. Active systems are proposed to ensure the regeneration along variable driving conditions. In this study, Photocatalyst-Plasma and Honeycomb (PPH) is proposed as an active and continuous regeneration system of DPF on the road. The results show a good feasibility of PPH system for PM regeneration with lower power consumption without an increasing pressure on the DPF.

The objective of this research was to study the effects of a CCRT®, henceforth called Diesel Oxidation Catalyst - Catalyzed Particulate Filter (DOC-CPF) system on particulate and gaseous emissions from a heavy-duty diesel engine (HDDE) operated at Modes 11 and 9 of the old Environmental Protection Agency (EPA) 13-mode test cycle Emissions characterized included: total particulate matter (TPM) and components of carbonaceous solids (SOL), soluble organic fraction (SOF) and sulfates (SO4); vapor phase organics (XOC); gaseous emissions of total hydrocarbons (HC), carbon monoxide (CO), oxides of nitrogen (NOx), nitric oxide (NO) and nitrogen dioxide (NO2), oxygen (O2) and carbon dioxide (CO2); and particle size distributions at normal dilution ratio (NDR) and higher dilution ratio (HDR). Significant reductions were observed for TPM and SOL (>90%), SOF (>80%) and XOC (>70%) across the DOC-CPF at both modes.

Since 2003, a concerted effort between Alcan Inc. (ARDC: Arvida Research and Development Centre) and the Aluminium Technology Centre (ATC) of the National Research Council of Canada is underway to develop a technology, dubbed SEED (Swirled Enthalpy Equilibration Device), to produce semi-solid aluminium feedstock. This technology, patented by Alcan Inc., is a simple process offering many advantages over thixocasting, especially for reducing the cost of feedstock. The process involves two main steps: 1) heat extraction to achieve a desired liquid/solid mixture, and 2) drainage of an excess liquid to produce a self-supporting semi-solid slug that is cast in a high pressure press. This paper reports that the SEED technology is applicable to a number of aluminium alloys and can be easily adapted to produce a wide range of slug dimensions. Furthermore, since the heat transfer plays a predominant role during the manufacture of the semi-solid slurry, its analysis is also presented.

Computer aided design (CAD) and computer aided engineering (CAE) have made great progress in the past two decades. Casting simulation software has become an important tool for foundry engineers to produce good castings and CAD-software is used by all modern designers. Time-to-market and quality could be further improved if designer and foundry man would work closer together, more specific if CAD and CAE software would be integrated. Therefore, software has been developed to integrate design optimization and casting process simulation with finite element software for stress calculations. This software can be used as a complete virtual design and production algorithm, which consists of three steps. First, design optimization is used to create an optimal geometry. Subsequently, casting simulation software is applied to calculate a proper gating and riser system to produce a sound casting.

For upcoming applications in the automotive domain, such as safety-critical applications, high dependable communication systems are needed. FlexRay already provides high transmission speeds and a set of fault-tolerance functions. In several non-automotive industries, the Time-Triggered Architecture (TTA) has already been established as means to implement safety-critical systems. The TTA has properties that have been proven theoretically, making development of safety-critical systems easier. FlexRay can be used as communication protocol in the TTA. This paper shows how to implement additional safety functions on top of FlexRay, which provide consistent communication for use in critical hard real-time applications. The COM-Accelerator is designed to relieve the host CPU by implementing the fault-tolerant communication layer in hardware. Therefore, the host does not need to handle the data exchange itself and is able to provide higher performance to the applications.

Open tanks and exterior surfaces of process heating equipment lose heat to the surroundings via convection, radiation, and/or evaporation. A practical way of reducing heat loss is by insulating or covering the surfaces. This paper presents methods to quantify heat loss and energy savings from insulating hot surfaces and open tanks. The methods include radiation and evaporation losses, which are ignored by simplified methods. In addition, thermal mass, such as refractory, conveyor and racking equipment, acts as a heat sink and increases heating energy use in process heating applications. This paper presents lumped capacitance and finite-difference methods for estimating heat loss to thermal mass, and savings from reducing this loss. The methods described above have been incorporated in free software, and are demonstrated using case study examples. The examples demonstrate the magnitude of the potential error from using simplified methods.

Materials with Oxygen Storage Capacity (OSC) are key components in the formulation of Three Way Catalysts (TWC) for more than 2 decades. To get advanced TWC catalysts complying with the coming more severe regulations, one needs among others to increase both the thermal stability and the redox properties of OSC materials. In terms of thermal stability, Rhodia obtained in the recent years significant improvements by developing a new wet process yielding pure phase and high surface area OSC materials even after harsh ageing conditions at temperatures higher than 1100°C [1, 2]. These materials are preferred precious metals carriers [3]. This paper deals with recent progress achieved in terms of redox properties of CeO2/ZrO2 mixed oxides. Increasing the bulk oxygen mobility of the CeZr mixed oxides is of great interest specifically to increase the conversion of the pollutants under transient modes. Already described materials [4, 5 and 6] show very high oxygen availability and mobility.

We describe a Joint Boost Power Converter and Injector Valve Model that we used to help develop and optimize the Woodward ECM3, 24 channel EFI driver system. Using the joint model, we found that the adaptive algorithm used to drive the injectors would not suffer from a non-stiff bus voltage as long as we could achieve the required valve closure time. The joint model then helped us find the optimum combination of IL, L, Vbus, Cbus, Coil Current Profile and the Average Power with respect to the valve closure time constraint. In addition, we used the model to gain insight into the effect of Pull-In Current levels on the Valve Closure Locus and the valve position response when a Pre-injection pulse is added to the Main-Injection cycle.

A new exhaust system has been developed to cope with post-SULEV (Super Ultra-Low Emissions Vehicle) regulation by newly designed hardware of exhaust system. This paper will describe the various new technologies used for achieving the post-SULEV standards, such as Conicat (cone-type metal catalyst), dual-wall pipe, pipe-type metal catalyst, ultra thin wall monolith and HC trap system for the improvement of catalyst light-off time. The tested data on 2.0L SULEV vehicle indicate that Conicat(cone-type metal catalyst) and HC trap (hydrocarbon absorbing catalyst) have more positive characteristics, and are expected to show the enhanced HC reduction performance with the optimization of emission system.

We have developed a Pd-intelligent catalyst with a self-regenerative function that is realized by the passage of Pd through consecutive solid solution and segregation states in and out of a perovskite crystal, and commercialized it for the first time in the world [1, 2, 3, 4, 5, 6, 7, 8 and 9]. In this study, we investigated the self-regenerative function of Rh as an alternative for Pd, in two types of Rh-perovskite (LaFeRhO3 and CaTiRhO3), and found that a CaTiRhO3 perovskite has an excellent capacity for the self-regenerative function of Rh. In a LaFeRhO3 perovskite with a composition similar to the Pd-perovskite (LaFePdO3), Rh was fixed so stably in the perovskite structure that it hardly segregated from the perovskite even in high temperature reduction atmospheres. However, in the CaTiRhO3 perovskite, with its A2+B4+O3 formula, the amount of Rh that actually segregated increased greatly in reduction atmospheres.