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Renewed interest in a gas turbine as an alternative driveline for heavy trucks within Volvo, driven by the demands for lower emissions, resulted in a pre-study during 1990-1992 and the development and testing of a demonstrator engine between 1993 and 2000. To achieve the demanding goals for efficiency and emissions, the engine was designed as a recuperated and intercooled two shaft powerplant with a low-emission combustor. Following a comprehensive aerodynamic and concept study, engine components were rig tested and the engine mechanical design was finalized. Two engines were built and tested in a rig and in a truck. Very low exhaust emissions were demonstrated during rig testing, with NOx as low as 0,22 g/kWh in a 13-mode test. The efficiency goal of 42 % was not reached, but given more development time the measured efficiency of 38,6 % can most certainly be improved. Still, it will be the fuel consumption that is the major disadvantage compared to a diesel engine.

Overturning on a road turn has always been a problem in vehicles. Based on a half- vehicle model, the results of vehicle stability after incorporating a hydraulic-actuator system is analyzed. It has been shown in the paper that the stability of a vehicle on a road turn can be increased promisingly by tilting its body towards the inner direction. The results are compared with the corresponding results of a conventional vehicle. Because of the feasibility and effectiveness of the proposed algorithm, the above system shows a definite improvement in vehicle stability.

The handling quality of a car is one of the most crucial parameters in the evaluation of the vehicle's overall performance. This quality is noticeably influenced by the structural and functional characteristics of the various components of the vehicle. The vehicle platform subsystems (i.e. steering, suspension, and braking) have major role in altering and tuning handling quality. It brings up special concerns in designing each of these mechanisms and need of having a comprehend understanding of their role in the handling characteristics of a vehicle. In this article, a general method for the optimization of steering system is presented. The investigation is focused on the geometrical parameters of a rack and pinion steering system, and their contribution on the handling characteristics. This kind of steering is common in medium class vehicles.

Hardware-in-the-Loop (HWIL) testing is a means for validating and verifying component designs in a system context. Most current HWIL work with electrochemical systems for automotive applications has focused on the pack level, providing valuable feedback to system designers. Further benefits are realized by implementing this concept earlier in the development process; applying test vectors to an individual cell, but attenuating the stimulus and feedback to pack levels. This paper reports on a cell-level HWIL system designed to evaluate electrochemical cells and associated subsystems for advanced hybrid-electric vehicles (HEVs). The architecture of the system is described along with an example of its application applied to a commercially available supercapacitor and a state-of-charge algorithm in an HEV-based configuration.

The development of Steer-by-Wire (SbW) systems for on-road use is a challenging task. In a joint industry effort several companies have teamed up in the TTA-Group SbW Working Group to develop an architectural cookbook for SbW. The working group started with the development of a concept document. It adopts IEC 61508 for the development of a reference SbW architecture for on-road use. The main focus of the working group will be achieved in a second step where common parts of the electronic architecture will be developed.

For the purposes of on-line control, e.g., in an automatic driving system, or of closed-loop directional control simulation, an optimal preview artificial neural network (ANN) driver model based on error elimination algorithm(EEA) is built. Then the optimal preview times are discussed in high frequency range in this system. The simulation results of optimal preview ANN driver model and Error Elimination Algorithm driver model are compared under the condition of different vehicle speeds and paths, which shows that the proposed approach is efficient and reliable enough, particularly for driver-vehicle closed-loop system.

The National Research Council of Canada (NRC) is commencing a new round of aerodynamic development of heavy trucks in partnership with Natural Resources Canada (NRCan), the Canadian Trucking Alliance (CTA) and the US Department of Energy (DOE). The program is meant to take second-generation, add-on technology from the wind tunnel to the fleet. The purpose is to reduce fuel consumption and greenhouse gas emissions. The benefit is that the fuel reductions pay the operators to improve their vehicle emissions. 1:10-scale model tests in the NRC 2m × 3m wind tunnel, followed by full-scale tests on a Navistar 9200 Day Cab with 40-foot trailer in the NRC 9m × 9m wind tunnel, were employed to develop the add-on devices of interest. The results demonstrated significant fuel savings from a combination of longer cab extenders, trailer skirts and trailer boat-tails that reduced fuel consumption as much as the contemporary aerodynamic cab packages.

With rising oil prices, the issue of energy economy in transportation is getting much attention. At the same time, new emissions standards for tractor-trailer vehicles introduce additional challenges for the manufacturers to achieve improvements in vehicle fuel economy. As part of the U.S. Department of Energy Office of FreedomCAR and Vehicle Technologies' Heavy Vehicle Aerodynamic Drag Consortium, Argonne National Laboratory is currently developing guidelines for the use of commercial computational fluid dynamics (CFD) software to facilitate energy efficiency improvements through improved aerodynamic design of tractor-trailer vehicles. The development of these guidelines requires the consideration of the sensitivity of the accuracy of the analysis to the various modeling choices available to the end user.

At 70 miles per hour, overcoming aerodynamic drag represents about 65% of the total energy expenditure for a typical heavy truck vehicle. The goal of this US Department of Energy supported consortium is to establish a clear understanding of the drag producing flow phenomena. This is being accomplished through joint experiments and computations, leading to the intelligent design of drag reducing devices. This paper will describe our objective and approach, provide an overview of our efforts and accomplishments related to drag reduction devices, and offer a brief discussion of our future direction.

A Diesel Particulate Filter (DPF) is needed to meet the Particulate Matter (PM) requirements of US EPA 2007 regulations for diesel engines. A catalyzed diesel particulate filter (cDPF or CSF) in combination with a diesel oxidation catalyst (DOC) is effective if the DOC has achieved light-off. However, for some applications, exhaust temperature will be too low to achieve DOC light-off. Therefore a reliable active regeneration means will be required. This paper presents a diesel-fired filter regenerator that works with an uncoated DPF. During regeneration, the thermal regenerator raises the exhaust temperature to 650 °C at the filter face at any engine condition, including idle. The thermal regenerator was tested on a cordierite filter placed on a heavy-duty diesel engine with cooled-EGR (2007 calibrations). THC, CO and NOx emissions, as well as opacity, in the tailpipe were measured at both steady state and transient engine conditions.

Due to the large size, high bulk density and high thermal expansion coefficient of the diesel particulate filter substrate; the conventional mounting system cannot provide the necessary radial mounting pressure. Mathematical and experimental results give the vibration and the back pressure force needed to mount the diesel particulate filter in the exhaust system. L-seal mounting support used in diesel particulate filter provides cushion to accommodate the linear tolerance of the substrate and the cone and also the necessary axial and radial mounting forces. L-seal axial and radial mounting forces are altered by type of material, surface characteristics, heat treatment and wire geometry. The proportional increase in compression force per unit weight during cycling shows dimensional consistency of the L-seal. The compression characteristics of A286 tremendously increase (>20%) during heat treatment as precipitation and hardening occurs.

Knitted wiremesh along with radial gas tight seals provide reliable mounting system for low temperature underbody converters. The compression characteristics of the wiremesh is modified by wire material, wire diameter, wire geometry, mesh crimp heights; wire density, wiremesh courses per inch, needle count, number of strands, wiremesh temper, wiremesh surface profile and surface characteristics. The radial mounting pressure provided by the wiremesh is matched with the mounting pressure requirement. Wiremesh systems can be tailored to any required radial mounting pressure from conventional to ultra thin-wall substrates. The wiremesh mounting system is proven durable, without any failure on more than 25 million underbody converters in light duty vehicles. Cp and Cpk show the capability of the manufacturing process. Thus the wiremesh mounting support is a viable alternate for low temperature gasoline and diesel applications.

The purpose of this paper is to examine the use of a surface mineralization process for general corrosion protection. More specifically, this paper describes the use of surface mineralization (SM) as a non-hazardous and environmentally benign alternative to cadmium plating and hexavalent chromate treatment for protecting fasteners from corrosion in off highway applications. An engineered surface is founded on a mineral-based product that forms a thin metal silicate surface fully involving the substrate metal. Completed laboratory cyclic testing of SM treated fasteners compared with cadmium plated and hexavalent-chromate treated fasteners to 180 cycles using the GM 9540P protocol have demonstrated a significant increase in corrosion resistance of components protected by the SM process.

Most pieces of mobile equipment (machines) produce an audible signal to indicate movement in the rearward direction. This signal is intended to alert nearby personnel of the potential danger associated with the machine moving in a direction where the operator may not be able to see people or objects in the machine path. Anyone who has been on or near a construction site recognizes the familiar “beep…beep…beep…” of this signal as the backup alarm. To be effective, the backup alarm must be discernible, timely, and relevant to those people where a reaction is intended. As machine designers respond to various sound directives for reducing sound emissions (including the backup alarm), the performance of the backup alarm is receiving special attention. An emerging solution is an alarm capable of sensing ambient sounds and producing an audible signal proportional to the sensed sound levels-a self-adjusting backup alarm.

E-spring is an optimized trend of springs for vehicle suspension systems. Experimental and transmissibility analyses of laminated fibrous composite E-springs are conducted. The mechanical and frequency-response-based properties of these springs are investigated experimentally at both of the structural and constitutional levels. Thermoplastic-based and thermoset-based fibrous composite structures of the E-springs are modified at micro-scale with various additives and consequently they are compared. The experimental results reveal that additives of micrometer-sized particles of E-glass fibers as well as mineral clay to an ISO-phthalic polyester resin of the composite E-spring can demonstrate superior characteristics. The transmissibility analysis of laminated fibrous composite E-springs reveals superior frequency ratio.

Suspension systems are designed by considering comfort and durability issues. If suspension systems are analyzed from the view point of acceleration and force transmission, two design criteria are obtained that can be used in optimum design of these suspension systems. For individual links of these suspension systems, these criteria are minimum transmissibility condition and percussion center of the links, which are derived through kinematical analysis. While minimum transmissibility condition can be imposed geometrically, location of percussion center of a link can be optimized by using finite element model of the link. It is shown that accelerations and reaction forces that are transmitted to the chassis of the vehicle can be reduced by considering these issues.

Measurements of soot and SOF emitting from automobile engines by conventional gravimetric method and soxhlet extraction method are difficult and time-consuming processes. The composition in the filter substrate may change during time-consuming analysis. Therefore an accurate and real time measurement method for particulate matter is the key demand for automobile industry. This paper describes a new concept for analyzing PM, which includes measurement of soot and SOF separately, as well as the total PM emission from automobile engine continuously. The concept comprises of the real-time measurement of soot emission with a diffusion charger (DC) combined with a specific dilution system. A differential flame ionization detector with separate sample line temperatures (47°C and 191°C), have been applied for the SOF measurement. The total PM is then expressed as the sum of soot and SOF mass.

In support of NHTSA's studies of heavy truck brake types and their effects on vehicle stopping performance and stability, the NHTSA Vehicle Research and Test Center (VRTC) has evaluated four foundation brake types on their Greening Brake Dynamometer. Several sample assemblies of each type of brake were tested to better understand variability. Braking tests were run under the “Laboratory Test Procedure for FMVSS 121D Air Brake Systems - Dynamometer” (TP- 121D-01) procedures. Afterward, the test scope was expanded to include higher speeds and higher severity conditions than those specified Test Procedure. This paper reports on the differences in braking effectiveness between two traditional S-Cam air brake types and two recently introduced Air Disc brake types. Burnish procedure trends are briefly discussed and compared. Responses of the pneumatic brakes to both constant-pressure and dynamic inputs are also compared and discussed.

In response to the appearance of formal regulations, CFR part 1065 subpart J, a new in-use emission measurement system was developed, the OBS 2000. The OBS 2200 uses partial-vacuum analyzers. The heated flame ionization detector (HFID), heated chemiluminescence detector (HCLD) and heated non-dispersive infrared analyzer (HNDIR) are all upstream of the sample pump. This design decreases the response time of the analyzers, lowers power consumption and minimizes the overall dimensions of the system by avoiding the use of a heated sample pump. The size of the heated zones is also minimized to reduce power usage. Typical power consumption of analyzer unit is less than 500 W. The overall dimension of the main unit is 350mm (W) × 330mm (H) × 500mm (D). Analyzer linearity checks as required by new regulations [1] for all available ranges will be presented along with cut point accuracies relative to full scale and percentage of point.

Axiomatic Design is a principal based method to help reduce or eliminate conceptual vulnerabilities early in the design process by clearly linking function requirements to design parameters creating a hierarchy of Design Matrices which are then evaluated relative to two axioms. This paper illustrates the use of Axiomatic Design methods to design a Smart Inlet Control Valve for heavy-duty air brake compressors operating with highly turbocharged inlet air. The example application shows how Axiomatic Design links with two other Product Development tools - Failure Modes and Effects Analysis and Taguchi methods.