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The location of the pelvis in the seated automobile operator is critical for proper packaging and seat comfort design. The pelvis is the skeletal structure which contains the hip joint (H-point) and ischial tuberosity (D-point). The orientation of the pelvis largely determines the curvature in the low back which is supported by lumbar supports in the seat back. A methodology has been developed that uses onboard video and pressure measurement systems to locate the pelvis. This system has been used in a mid-sized vehicle on seated operators driving the vehicle on the highway. This paper describes the methodology and the location of the pelvis in seated automobile operators.

A vehicle laboratory has been developed in which the vehicle operator's posture, pressure distribution, muscle activity, and comfort can be measured while driving on the highway. This instrumented vehicle uses video camera, pressure mats, electromyography, and questionnaires to make these measurements. There is an on-board PC486 to record the data fro later off-line analysis. These data are useful for developing design criteria for seating comfort as well as investigating the real-life position that the operator sits in the vehicle package while driving the vehicle on the highway.

This paper reports the development of vapor/liquid visualization systems based on an exciplex (excited state complex) formed between dimethyl- or diethyl-substituted aniline and trimethyl-substituted naphthalenes. Quantum yields of individual monomers were measured and the exciplex emission spectra as well as fluorescence quenching mechanisms were analyzed. Among the many systems and formulations investigated in this study, an exciplex consisting of 7% 1,4,6-trimethylnaphthalene (TMN) and 5% N,N-dimethylaniline (DMA) in 88% isooctane was found to be the best system for the laser-induced exciplex fluorescence (LIEF) technique, which is used to observe mixture formation in diesel or spark ignition (SI) engines. Observation of spectrally separated fluorescence from monomer in the gas phase and from exciplex in the gasoline fuel [1] requires that the exciplex forming dopants have boiling points within the distillation range of gasoline (20 to 215°C).

Our research contributes to the overall attempt to gain knowledge of the fluid dynamical processes in engines by applying a new measurement technique called LIPA (Laser Induced Photochemical Anemometry). It concentrates on detecting fundamental flow and mixing mechanisms by performing experiments on the induction stroke in an axisymmetric motored water analog model of a four stroke IC engine. We present results of the investigations done at an engine speed of 20 RPM in water (corresponding to 340 RPM in air) at three different valve lifts (3, 6, and 9 mm). Maps containing velocity vectors depict in 2D a toroidal recirculation pattern that scales with cylinder volume and they suggest that the recirculation pattern possesses the highest degree of order -- thus least mixing -- for 9 mm valve lift and the lowest for 3 mm valve lift. A fluid dynamic model on the basis of freestream jet characteristics has been proposed to account for this phenomenon.

The effect of compaction and fiber volume fraction on the transverse permeability of a fluid flowing through stacked layers of fiber mats has been experimentally studied. A Unifilo-101 random mat of continuous glass strands, held together with a binder soluble in styrene was used. The stacked layers were compacted using a Wabash instrumented press. Changing the maximum load, resulted in different fiber volume fractions. Mixtures of glycerol and water with viscosities between 85 and 100 mPa-s were used. This fluid is passed in a rectangular cell, through the fibers arranged transverse to the direction of flow. The pressure drop across the mat and the flow rate were monitored. The study was carried out at different flow rates of the fluid and was repeated for other fiber volume fractions. A power-law relation was observed between the permeability and the fiber volume fraction.

This paper presents a study of the effects of a resin soluble thermoplastic preform binder on the Resin Transfer Molding (RTM) process. The focus of the study is the rate of dissolution of the binder in the resin and the associated viscosity changes in the resin. Tests on the rate of binder dissolution from continuous strand glass mats show that after one minute of exposure to styrene, roughly half of the medium solubility binder from Unifilo 750 will dissolve and all of the high solubility binder from Unifilo 101 will dissolve. As the concentration of binder in the resin increases from 0 to 5 wt. percent, the viscosity of a vinyl ester resin increases from 125 cps to 280 cps. The viscosity of the resin has also been monitored in continuous flow experiments through the mats placed in a rectangular plague mold, at different flowrates. In these runs, the viscosity varied from 245 mPa-s to 145 mPa-s when the fill time was 2.2 minutes.

As environmental regulations become more stringent, manufacturers are confronted with the task of product-design considering environmental impacts. Life Cycle Analysis (LCA) is a developing technique that attacks this problem. LCAs provide environmental information for decision making by consumers, manufacturers, and governments. These decisions significantly affect the ability to maximize source reduction, re-use, recyclability, and recycled content. LCAs can aid in diminishing the negative impact a product has on the environment and can be utilized as a partial solution of our nations' (worlds') growing waste management problem. To date, the application of LCAs has varied from product comparison to process development and improvement. The results from these analyses have differed because of differing assumptions and differing choices of boundary conditions. An appropriate Life Cycle Analysis should be consistent across products, locations, and especially across experimenters.