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The use of methanol as a fuel in transit buses is being demonstrated through the use of diesel engine retrofits and an ignition improver to methanol. This project is aimed at retrofitting the Detroit Diesel Corporation (DDC) 6V-92TAC diesel engine in a GM RTSII bus to operate on methanol. The engine is modified by installing higher compression ratio pistons, higher flowrate mechanical fuel injectors, and a different blower. The bus fuel system is also modified to accommodate the properties of methanol. New fuel lines are installed, and the diesel fuel tank is replaced with two stainless steel tanks. A high-pressure electric fuel pump and a fuel cooler are used to prevent methanol from boiling in the engine. Currently, three buses have been retrofitted. The buses operate at the Southern California Rapid Transit District (SCRTD) in Los Angeles, California.

Due to the special requirements of the transit bus operator's function, the environment can be a very difficult place to work, especially for large males and small females. This paper addresses the design of bus operator work stations to accommodate people from the 5th percentile female to the 95th percentile male. Results from a bus operator survey, task analysis and an evaluation of a proposed bus operator work station are presented. While attempting to maintain the amount of adjustment to a minimum, adjustment greater than present practice was included in components like the instrument panels, seat and steering column. The controls were grouped in the instrument panels by their function. Controls dealing with passenger pick-up and delivery are located in a right-hand instrument panel. A jury of over one hundred subjects evaluated the proposed work station. The jury evaluation showed that the work station will accommodate the above population extremes.

Bus remanufacturing has grown into a nationally recognized field in transit industry. Complete restoration of critical structural components is very important for its sound growth. Structural parts are examined to reveal their deterioration in unexposed areas. Road call data is compared to analyze the performance of remanufactured buses. Development of a positive scope of work and quantification of contractor evaluation criteria are discussed.

Furnishing transit service to smaller urban communities in a way that is workable physically and economically is the main point of discussion in this paper. The important issues relating to public transportation in small urban areas include financing, community service, institutional considerations, and image. Finding the best system for each respective community is the relevant problem, the systems must be planned to enable each community to grow and prosper.

Existing transit services in the Washington, D.C. area are faced with increasing costs and diminishing patronage, resulting in declining service. Top priority tasks are to provide for the improvement of existing bus services, planning for integrated and efficient bus operation before, during and after construction of the rail rapid transit system; and initiation of new and expanded passenger and service improvements. Future transit planning must recognize, however, that land use and travel patterns dictate the choice of travel mode. In fact, highway improvements will also be required in order to serve the land development and travel generated by the transit lines themselves.

Transition materials which are used to join dissimilar metals such as steel and aluminum on automobiles are described in this paper. The problems associated with conventional methods of joining these two metals include galvanic corrosion, brittle welds, reduced mechanical properties and reduced design flexibility. These problems are solved through the use of clad transition materials at the joints. Transition materials are fabricated by roll bonding dissimilar metals to form the clad materials and subsequently forming the materials to the desired configurations. The clad material allows the actual transition from one metal to the other to occur at the clad bond interface and thus only similar metal joints exist in the assembly. Welding studies describe the high strength and ductility of steel to aluminum joints through the use of steel clad aluminum transition materials.

A research and development program is being conducted at the Saft Advanced Technologies Division in Hunt Valley, Maryland, to double the energy density of a thermal battery. A baseline battery has been developed with lithium/iron disulfide chemistry to meet a set of military requirements. A study of transition metal fluoride cathodes to replace iron disulfide is in progress for an improved battery. Development of a lithium/copper(II) fluoride (CUF2) couple is proceeding by iterative testing of single cells. LiAl/CuF2 cells have produced 227 Wh/kg. This exceeds the specific energy of state-of-the-art cells with iron disulfide by nearly 40%. The copper fluoride cells average 2.44 volts when discharged at a current density of 200 mA/cm2.

This paper presents a methodology for tool-assisted development of software for electronic control units in cars. Because of increasing complexity the developer requires a set of tools that cover the whole development process. In this paper the process is separated into several phases. Ideally after analysis there is a specification phase, where executable but hardware independent models are created. After that in the Design phase the hardware architecture is designed and partitioning of the models onto the network of ECUs is performed. Here the appropriate architecture is chosen. This paper shows the seamless methodology from the Specification phase tool ‘ASCET-SD’ to the Design phase tool ‘Virtual Component Co-Design’ (VCC) with respect to the overall design flow. Several ways of doing the transition considering intellectual property protection, target dependency accordingly independency, and model semantics are considered.

Supersonic wind tunnels with much lower stream disturbance levels than in conventional tunnels are required to advance transition research. The ultimate objectives of this research are to provide reliable predictions of transition from laminar to turbulent flow on supersonic flight vehicles and to develop techniques for the control and reduction of viscous drag and heat transfer. The experimental and theoretical methods used at NASA Langley to develop a low-disturbance pilot tunnel are described. Typical transition data obtained in this tunnel are compared with flight and previous wind-tunnel data and with predictions from linear stability theory,

Recent work at the University of Waterloo addressed the hot stamping of a lab-scale B-pillar using a heated and cooled die to produce a tailored part with a soft and hard region for which the microstructure was predominantly bainitic and martensitic, respectively. This paper addresses the tensile properties of the transition zone (hard to soft region) within this tailored hot stamping using experimental and numerical methods. Vickers hardness measurement showed that the fully softened and hardened material conditions were achieved across a 25 mm transition zone. Sub-size ASTM uniaxial tensile specimens were cut from the transition zone and pulled to failure. Due to the large variation in material properties within the gauge length of the specimens, apparent uniform elongations measured across the gauge length ranged from 0.02 to 0.04 engineering strain, while the calculated engineering ultimate tensile strength (UTS) varied from 798 to 913 MPa.

Commercial Heavy vehicles (CHVs) are an efficient and reliable link between marine, railroad, and air transportation nodes. The vehicle braking power imposes an important constraint in the allowable vehicle speed. The compression brake augments the vehicle retarding power and is currently typically used as an on-off device by experienced drivers. Hardware and software advances allow modulation of the compression brake power through variable valve timing, and thus, enable integration of the compression brake with service brakes. To analyze how much the compression brake affects vehicle speed during braking, we develop a crank angle engine model that describes the intrinsic transient interactions between individual cylinder intake and exhaust gas process, turbocharger dynamics, and vehicle dynamics during combustion and variable brake valve timing. The model is validated using experimental data.

Partially premixed combustion (PPC) is a promising way to achieve high efficiency and low engine-out emissions simultaneously in a heavy-duty engine. Compared to Homogeneous Charge Compression Ignition (HCCI), it can be controlled by injection events and much lower HC and CO emissions can be achieved. This work focuses on the transition from HCCI to PPC and combustion and emissions characteristics during the process are investigated. Injection strategies, EGR and boost pressure were the main parameters used to present the corresponding effect during the transition.

In a previous study, in order to investigate the effect of charge stratification on combustion behavior such as combustion efficiency and combustion phasing which also largely affects the emissions, an experiment was conducted in a heavy-duty compression ignition (CI) metal engine. The engine behavior and emission characteristics were studied in the transition from HCCI mode to PPC mode by varying the start of injection (SOI) timing. To gain more detailed information of the mixing process, in-cylinder laser diagnostic measurements, namely fuel-tracer planar laser induced fluorescence (PLIF) imaging, were conducted in an optical version of the heavy-duty CI engine mentioned above. To the authors’ best knowledge, this is the first time to perform fuel-tracer PLIF measurements in an optical engine with a close to production bowl in piston combustion chamber, under transition conditions from HCCI to PPC mode.

The partially premixed combustion (PPC) concept is regarded as an intermediate process between the thoroughly mixed Homogeneous charge compression ignition (HCCI) combustion and compression ignition (CI) combustion. It’s a combination of auto-ignition mode, a fuel-rich premixed combustion mode, and a diffusion combustion mode. The concept has both high efficiency and low soot emission due to low heat losses and less stratified fuel and air mixtures compared to conventional diesel CI. The mechanisms behind the combustion process are not yet very well known. This work focuses on the efficiency and the in-cylinder process in terms of fuel distribution and the initial phase of the combustion. More specifically, double injection strategies are compared with single injection strategies to achieve different levels of stratification, ranging from HCCI to PPC like combustion as well as poor (43%) to good (49%) of gross indicated efficiency.

An experiment was conducted to investigate the effect of charge stratification on the combustion phasing in a single cylinder, heavy duty (HD) compression ignition (CI) engine. To do this the start of injection (SOI) was changed from -180° after top dead centre (ATDC) to near top dead centre (TDC) during which CA50 (the crank angle at which 50% of the fuel energy is released) was kept constant by changing the intake temperature. At each SOI, the response of CA50 to a slight increase or decrease of either intake temperature or SOI were also investigated. Afterwards, the experiment was repeated with a different intake oxygen concentration. The results show that, for the whole SOI period, the required intake temperature to keep constant CA50 has a “spoon” shape with the handle on the -180° side.

The Quality Control function in the domestic automobile industry is in transition. The changing role is predicated on the question “who will be responsible for Quality?”. Traditional approaches had a separate quality control organization using “On-Line” inspection techniques. A better method it seems would assign quality responsibility to the production activity. “Real-Time” data would be supplied on a regular basis to enhance the decision making process. This presentation will describe a method utilized by Ford Body and Assembly Stamping Operations for the transition from the traditional quality control organization to the quality assurance concept.

IN discussing the transition from torque converter to fluid coupling operation. the author explains that the point where the transition should be made and the performance range that should be favored depends on the type of service required of the vehicle. For example, he says that a good coupling range is important in passenger cars, where a good deal of the operation is at part load, whereas in city buses, maximum torque multiplication is more important to give the high acceleration expected of these heavy vehicles.

Perhaps no other single development has given so much impetus to the single-hand held power tool field as has the lightweight, compact, gasoline-powered engine. This paper describes the many innovations required to develop the three models of the Ohlsson & Rice Compact engine. This versatile power package, weighing less than 4 lb, has opened up new markets for the imaginative tool and equipment design engineer. To date it has been adapted to such widely diversified equipment as motor bikes, cultivators, saws, generators, and similar units. Even wider application is inevitable because of its ruggedness, portability, and easy starting.

An empirical model for transition to turbulence in oscillatory flows in straight tubes is proposed. The model, fashioned after a correlation for transition of a boundary layer on a flat plate, yields the laminar flow momentum thickness Reynolds number that must be met before transition to turbulence will occur. The transition point is located by comparing this to the actual momentum thickness Reynolds number. Since in one-dimensional computation, as is typically employed in engine simulation codes, the momentum thickness Reynolds number cannot be computed, a scheme is proposed for estimating it in terms of the position within the cycle, the maximum value of the diameter Reynolds number within the cycle, Remax, and the dimensionless frequency, Valensi number, Va. Another parameter required in the calculation of the point of transition is the turbulence intensity value within the core flow and external to the boundary layer.

In motorcycles, the materials of frame have been switched from steel to aluminum for the purpose of reducing weight while improving the rigidity of chassis. It was made possible to use aluminum frames for a number of commodity categories, by the development of technology through new structural designs to make the most of the characteristics of aluminum, the advancement of computer simulation system and the progress in material and production engineering. As the result of adopting aluminum for the frame, much higher performance has been realized by achieving a 40% reduction in the developed frames consisting of extrusions and castings for sports-oriented motorcycles and by suppressing the increase in fuel consumption. For low-priced utility vehicles such as scooters, the manufacturing process has been simplified by the development of the die cast two-split module frame.