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This study relates the structural stiffness and kinetic energy of impact to the dynamic response of a belted vehicle occupant. Acceleration time histories of impact for structures with different stiffnesses were obtained by performing a finite element analysis using the LS-DYNA3D finite element program and a model representing a structural member made of AISI 4340 steel. For the human body dynamics analysis, the Articulated Total Body (ATB) computer program was used to perform six simulations of a 50 percentile male restrained by a 3-point seatbelt system for a co-linear -Gx impact.

A new statistical procedure to use with the Engine Manufacturers Association 200 hour duraability test for alternate fuels evaluation has been proposed. Data from a laboratory endurance test is used to illustrate the proposed statistical procedures. The assumptions for each statistical test are given. Further, problems encountered during the endurance test which affected the validity of the statistical tests are discussed.

Multivariate statistical procedure has been used to compare various alternate fuels based on the residue formation on selected engine parts. The results from the Multivariate Analysis of Variance procedure which does the simultaneous comparison of the chosen response variables are presented. The assumptions for this test procedure are given. Problems which could affect the validity of the statistical procedures for the endurance test are discussed. Data from a 200-hour EHA laboratory screening endurance test is used to illustrate the statistical methods. Results from the statistical analysis of the experimental data were in close agreement with the engineering interpretation of the observed differences between fuels. Critical engineering interpretation of the statistical results is still required due to the high sensitivity of the statistical analysis.

The multivariate statistical procedure has been used to compare various alternate fuels based on the long term engine performance. The results from the multivariate analysis of covariance procedure, which does the simultaneous comparison of the chosen response variables, were adjusted for time of engine operation since the time factor was found to be significant. The assumptions for this test procedure are presented. Problems which could affect the validity of the statistical procedures for the laboratory endurance test are discussed. To illustrate the statistical method, data from a laboratory screening endurance test was used. Results of the analysis were in close agreement with the engineering interpretation of the observed differences between fuels.

The application of a multiple polynomial regression procedure for optimization of design and performance parameters has been presented. To illustrate the statistical method, data from a laboratory test of an exhaust emission reduction device was used. There were four factor variables for which the response was constructed. Among the factor variables two were design parameters; the remaining two were the operating parameters. The selected response variables were CO, NO, and HC's. The assumptions for the analysis procedure are presented. Problems which could affect the validity of the statistical procedures for the design optimization are discussed. Experimental verification of the optimization results was performed. Overall agreement between the predicted level of pollutants reduction and measured values did not differ by more than ten percent.

The crush behaviors of hollow square columns made of 45 different materials with emphasis on aluminum alloys and at two impact energy levels were simulated with FEA software DYNA3D. The force response curves based on the FEA simulation results were studied. Analysis of variance, cluster analysis, and principal component (PC) analysis were employed to analyze the data with SAS programs. The regression equations for calculating the peak force and time duration are given. The significance of the material properties and the impact energy levels to the peak force and the time duration are discussed. Finally, a procedure to predict the force response characteristics for a new material was suggested based on the current established database.

The objective of this study is to relate energy absorption characteristics to selected material properties and to establish a methodology that allows one to determine some of the material properties for maximum energy absorption. The finite element program DYNA-3D and its associated pre and post processors were used. The model used is a hollow square column. Five properties of the materials were included in the analysis: (i) Density (ii) Elastic Modulus (iii) Tangent Modulus (iv) Yield Strength, and (v) Poisson Ratio. The Response Surface Method in conjunction with the canonical analysis were employed to locate the optimum or near optimum levels of the properties and then to determine the equation of the response surface in an area near the vector of optimum levels. For the given levels of three out of five material properties used in the study, one can calculate the remaining two material property levels to achieve the near-optimal energy absorption.

The flow of diesel fuel through multi-hole injection nozzles is well understood. There are, however, no comprehensive experimental results for the design of injection nozzles for alternate fuels. A steady state flow generator was designed and employed to analyze the effects of the physical fuel properties and the needle lift on the discharge coefficient for the nozzle orifice. Three fuels were tested: diesel reference fuel, a 50/50 mixture of diesel fuel and sunflower oil, and 100%. sunflower oil. The fuel viscosities range from 3.0 cS to 30.0 cS at 40°C. Five injection pressures ranging from 3.5 to 13.8 MPa, and eight increments of needle lift between 0.031 and 0.940 mm were used in this investigation. A significant influence of needle lift, injection nozzle pressure, and physical properties of fuels on the flow coefficient in the normal operating range of a typical diesel engine was proven.

For the diesel engine performance analysis, the authors have developed computer programs that are implemented in the Statistical Analysis System (SAS). Programs have been developed specifically for the analysis of the diesel engine performance, residue formation on the internal engine parts, and fuel injection line pressure traces on the different alternative fuels while using EMA cycle. For the diesel engine testing, the consistency of the type of data and the experimental designs makes it possible to develop a system of SAS programs to analyze and report the data. The modularity of these programs makes adaptation from one trial to the next a simple procedure. Results from the analysis of the experimental data were in close agreement with the engineering interpretation of the observed differences between fuels. However, careful engineering interpretation of the results is required due to the high sensitivity of the statistical analysis.