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While many composite monocoque and semi-monocoque chassis have been built there is very little open literature on how to design one. This paper considers a variety of issues related to composite monocoque design of an automotive chassis with particular emphasis on designing a Formula SAE or other race car monocoque chassis. The main deformation modes and loads considered are longitudinal torsion, local bending around mounting points, and vertical bending. The paper first considers the design of elements of an isotropic material monocoque that has satisfactory torsional, hardpoint, and vertical bending stiffness. The isotropic analysis is used to gain insight and acquire knowledge about the behavior of shells and monocoque structures when subjected to a vehicle's applied loads. The isotropic modeling is then used to set initial design targets for a full anisotropic composite analysis.

Current projections for the crop mix in the Bio-Plex and the future Lunar bioregenerative life support system indicate that without supplemental oil production, the crew's diet will be extremely low in fat, with little refined oil available for food processing or preparation. Although soybeans, peanuts and dwarf brassica (similar to canola) have been suggested as oil crops, each one poses significant problems either in horticulture, harvesting, productivity or byproduct utilization. An alternative to plant oils is “single-cell oil” or SCO. Lipid-accumulating “oleaginous” micro-organisms may accumulate up to 60% of their dry weight as triglycerides. Their high growth rates enable them to synthesize lipids with far greater productivity than higher plant systems. The current top candidate species for use in a bioregenerative system is a yeast, Cryptococcus curvatus.

The food processing and preparation subsystem for bioregenerative lifesupport must combine food produced in-situ with resupplied food ingredients to provide a nutritionally balanced, palatable and varied diet for the station crew. We have approached these goals by developing a database of individual foods including recipe and processing information, panel acceptance data, nutritional analyses and cost estimates. Subsequently a linear programming optimization is used to select from among these foods a low-cost diet subject to constraints on nutrient content, overall acceptability, variety, and crew labor input. The database design, preliminary sensory testing results, and an optimized 1-day food list are presented..

Using synchrotron x-radiography and mass deconvolution techniques, this work reveals strikingly interesting structural and dynamic characteristics of the direct injection (DI) gasoline hollow-cone sprays in the near-nozzle region. Employed to measure the sprays, x-radiography allows quantitative determination of the fuel distribution in this optically impenetrable region with a time resolution of better than 1 μs, revealing the most detailed near-nozzle mass distribution of a DI gasoline fuel spray ever detected. Based on the x-radiographs of the spray collected from four different perspectives, enhanced mathematical and numerical analyses were developed to deconvolute the mass density of the gasoline hollow-cone spray. This leads to efficient and accurate regression curve fitting of the measured experimental data to obtain essential parameters of the density distribution that are then used in reconstructing the cross-sectional density distribution at various times and locations.

The effect of rear splitter plates and base cavities on the near wake behind a ground vehicle body above a moving ground plane were studied. Static pressure taps on the base of the body were used to measure both the mean and fluctuating pressures acting on the model base. Hot wire anemometry and flow visualization were used to study the effect of splitter plates and cavities on the near wake velocity field. The effects of varying ground clearance and of the moving ground on the base pressure were also studied. It was determined that some splitter plate configurations affect the base pressure distribution by forming a low pressure vortex on one side of the plate with high pressure fluctuations and altering the flow on the opposite side of the plate to raise the mean pressure. The suction region could be eliminated by moving the splitter plate to the model edge to form a side of a cavity. A full four sided cavity was able to increase the overall base pressure by 11% on the model.

An advanced multi-domain CFD analysis approach is proposed to calculate the scavenging flow process in motored two-stroke engines. An implicit and conservative treatment at the domain interface is developed which offers significant speedup in convergence. An arbitrary Lagrangian-Eulerian approach for moving grid and a grid remeshing technique for grid sliding at engine cylinder/transfer ports interfaces are used for efficiency and accuracy. A three-dimensional simulation of the Mercury Marine research two-stroke engine is carried out to demonstrate the approach. Six computational domains are used which naturally represent the geometries of the cylinder, engine dome, exhaust and transfer ports. The influence of boost port inclination angle on the scavenging process of the two-stroke engine is also studied numerically. The computation is supplemented with a standard two-equation turbulence model with compressibility correction.

The technologies of recycling Reaction Injection Molded (RIM) polyurethane polymers have been refined to the stage of commercial reality. Chrysler Corporation is in the process of qualifying the use of automotive fascia containing recycled RIM thermoset polymers. This will mark the first use, in North America, of a recycled RIM thermoset polymer into a class A surface exterior automotive part. This was made possible through a close working relationship with Polyrim Green Lane, a division of Decoma International, and Dow Plastics. The described process technology allows the recycle of painted and unpainted process scrap, and potentially post consumer scrap, into the same application without the loss of surface quality or polymer performance. This will divert these materials from the waste stream that is currently being landfilled.

The transmission of sound through automotive glazing materials was investigated. The sound transmission loss in one-third octave bands of several different automobile windows was measured at a testing laboratory. The materials tested included monolithic (single-layer) glass, monolithic polycarbonate, and a double glazing with an air gap in between the two panes. The experimental data are given in the paper. Subsequently, a computer spreadsheet program was written and developed to predict the sound transmission loss of single-layer glazing materials, using empirical equations found in the literature. The predicted sound transmission loss values showed good agreement with the experimental values. The sound transmission loss spreadsheet is a useful, easy-to-use tool to predict the acoustic performance of automobile window glazing materials.

Several different automobile windows were tested for transmission of noise Bench-scale flow noise tests, full-scale wind tunnel flow noise tests, and acoustic tests were performed The windows tested were the front side windows of a Chrysler sedan The transmission of external airborne noise was measured in a hemianechoic chamber at the Chrysler Technical Center A loudspeaker was used as a white noise source The transmission of the white noise into the vehicle interior was measured Aeroacoustic or flow noise tests were performed in the Chrysler Wind Tunnel in Chelsea, Michigan The test car was placed in a 112 km/hour flow and the resulting flow-induced noise was measured in the vehicle interior Bench-scale flow noise tests were performed at the Cornell University Low Noise Wind Tunnel, using the same set of window constructions The paper describes the results of all three types of tests The bench-scale test data from the Cornell University Wind Tunnel correlated well with the corresponding data measured in the Chrysler wind tunnel

This paper demonstrates the methods used to design an automobile engine cooling system. Basic terminology associated with the cooling system is defined. Topics covered include the radiator, fan, and coolant. The radiator is described in detail. The advantages of aluminum over copper/brass radiators are discussed, as well as the numerous tube, fin, and core designs of automobile radiators. Finally, experimental methods used in radiator and cooling fan selection are discussed. The experimental methods include dynamometer testing and the development of radiator/fan pressure drop vs. volumetric flow rate curves. Experimental data for radiator/fan curves of a typical racing car cooling system are presented. In addition, analytical techniques used to determine the maximum cooling capacity of radiators used for the Comell University Formula SAE Racing Car Team 1996 are described.

Both conventional and newly developed materials used in unique applications have played an important role in making the Chrysler gas turbine engine a practical powerplant. The new low-cost materials developed by Chrysler Metallurgical Research include, (a) a series of iron-base super alloys having equivalent or superior life to aircraft type alloys, (b) heat resisting iron aluminum alloys for elevated temperature service under low stress application, and (c) long life rubbing seal materials that operate satisfactorily from ambient temperature up to 1200°F and above. These materials appear to meet all present or immediate high temperature alloy requirements for a competitive mass produced automotive turbine.

General laboratory and testing procedures employed by the Chrysler Corporation in the development of its automotive gas turbine powerplant are discussed, with particular emphasis on facilities, instrumentation requirements, component fixtures, and complete powerplant tests. Some specific development problems and their solutions are presented along with some performance test results.

Paper is concerned with continuous data analysis using analog computer techniques. The author discusses briefly some of the possible techniques available. There are many variations or, and ramifications to, the circuits discussed. The type of analysis, the author points out, is an integral and important part of the design of any experiment.

A chemical approach and simple test apparatus are combined to study engine distributor cap deterioration. This paper describes a convenient test which correlates qualitatively with other tests and field experience. The apparatus produces an environment which is similar to that found in use under severe conditions. With this apparatus, critical experiments were performed. Moisture and electrical stress appear to be the major factors in cap deterioration.

A recently developed technique, crossed-plane imaging, is extended to measure instantaneous flamelet surface normals in a single-cylinder, optical SI engine. Two simultaneous, orthogonal acetone PLIF images are used to measure the instantaneous flamelet orientation in three dimensions. The images are also used to measure contours of constant mean reaction progress variable < c> and the mean flamelet crossing density. Statistics of the flamelet surface normal are presented in spherical coordinates in terms of a polar angle, f, and an azimuthal angle,q; the pole is aligned with the normal to a constant surface. The data are used to estimate marginal probability density functions (PDF's) in f and q. The estimated marginal PDF's are found to be well represented by the same functional forms applied previously to turbulent V-flames. The flamelet surface density and the mean fractional increase in flamelet surface area due to turbulence are also estimated.

Nitrate concentration in spinach and lettuce is known to be influenced by light quantity. The enzyme nitrate reductase is regulated by phytochrome in some species, and in the presence of light, electrons that reduce nitrite to ammonium come from photosynthetic electron transport. It was hypothesized that light quality as well as light quantity may be used to manipulate nitrate concentration in spinach. To test this, narrow-band wavelength light-emitting diode (LED) sources (670 nm and 735 nm peak emission) were utilized in combination with cool white fluorescent (CWF) lamps. Nitrate concentration was compared in spinach seedlings grown for four weeks under CWF, followed by one of three 5-day pre-harvest light treatments. The three different light quality regimes were 1) CWF, 2) CWF + RED (670 nm) LED, and 3) CWF + FR (735 nm LED).

In bioregenerative life support systems, crop residues represent a source of biochemical energy for production of chemicals, pulp products and secondary foods. Hydrolysis of the structural carbohydrates in biomass produces edible glucose as well as various 5-carbon sugars usable by microorganisms. However, the biomass must be pretreated before hydrolysis to remove minerals useful as plant nutrients, break down lignin, and improve access of the enzymes to the carbohydrates. Some pre-treatments also hydrolyze part or all of the hemicellulose, leaving purified cellulose. For use in space, pretreatments must be safe, rapid and as complete as practicable. This paper will present a process comparison of three “space-compatible” pretreatment methods for lignocellu-losic crop residues from bioregenerative life support systems. Ozonation, alkaline hydrogen peroxide, and strong alkali treatment use only regenerable materials and mild processing conditions.

Synchrotron x-radiography and a novel fast x-ray detector are used to visualize the detailed, time-resolved structure of the fluid jets generated by a high pressure diesel-fuel injection. An understanding of the structure of the high-pressure spray is important in optimizing the injection process to increase fuel efficiency and reduce pollutants. It is shown that x-radiography can provide a quantitative measure of the mass distribution of the fuel. Such analysis has been impossible with optical imaging due to the multiple-scattering of visible light by small atomized fuel droplets surrounding the jet. In addition, direct visualization of the jet-induced shock wave proves that the fuel jets become supersonic under appropriate injection conditions. The radiographic images also allow quantitative analysis of the thermodynamic properties of the shock wave.