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A facility for the aerodynamic testing of scale model vehicles has been developed. Suitable test section geometry, ground plane simulation, model setup technique, flow quality, and aerodynamic force and moment measurement capability are provided for automobile models of 1/4 to 3/8 scale. The maximum velocity of 160 mph enables 3/8 scale, 120 in wheelbase vehicles to be tested at Reynolds numbers approaching 5 × 106, based on wheelbase. A 3/8 scale model in a 160 mph airstream is dynamically similar to full-scale tests at 60 mph. Details of the facility are described.

This paper summarizes an analysis, design, and test project in which a dummy chest structure was developed. The chest consisted of mechanical elements that had been characterized by computer simulations as giving responses to blunt frontal impacts necessary for biofidelity. An analysis of mechanical rib structures indicated that materials having a high ratio of yield stress to modulus of elasticity were required. Only metals having unusually high yield strengths, such as spring steels, qualified. A mechanical system was developed with steel ribs pivoted at each end as a primary spring. A secondary spring was a pair of commercially available die springs acting in parallel with the ribs after 25.4 mm (1.00 in) deflection. A fluid damper was developed to provide the damping. The chest structure was tested under conditions modified from those used by Kroell. The modifications were holding the spine rigidly and reducing the impact masses.

This study explores the application of viscoelastic modeling for characterization of the response of the brain to impulsive loading with the objective of learning whether such models could exhibit the same time dependency of strain or likelihood of injury, as exhibited by the Severity Index, HIC Index, Wayne Tolerance Curve, and other similar representations of tolerance. The mathematical relationships between viscoelastic properties and the corresponding time dependency of tolerance are shown for Newtonian, Bingham plastic, and Pseudo-Bingham, as well as more general behavior. Preliminary static and dynamic tests upon small mammalian material are described with particular attention given to strain in the vicinity of the brainstem as a function of loading profile. Both the theoretical and experimental results show that the falling time dependency of the above indexes can be interpreted in terms of nonlinear viscoelastic response.

The intent of this paper is to put into proper perspective the relationships among the vehicle, the thermodynamic cycle, and the combustion process as they relate to exhaust emissions from a gas turbine-powered passenger car. The influence of such factors as car size, installed power, regeneration, and other cycle variables on level road load fuel economy, and on the production of oxides of nitrogen and carbon monoxide, are examined. In limited checks against experimental data, the mathematical model of the combustor used in this study has proved to be a reliable indicator of emission trends. The calculated emission levels are not final, however, with deficiencies subject to improvement as new combustor concepts are developed.

Interactive graphics is an aid which eliminates the data management problems that arise when manually preparing finite element models. Line and surface data representations of sheet metal automotive stampings are displayed on a cathode ray tube (CRT), and these data are then used for building finite element models. Elements are built by creating node points with the light pen or by using automatic mesh generating techniques. By using the interactive capability, the user immediately sees the results of his modeling decisions and can make changes in his model as a result of viewing his work. The interactive graphics system allows the user to define his elements, load cases, boundary conditions, and freedom sets without worrying about the grid point or element numbers. All information is communicated through the use of either the light pen or the keyboard. As information is supplied about the model, it is stored in a data base for review and possible change.

The equations of lateral motion response for four wheeled vehicles are developed for external disturbance inputs. Experimental data is obtained through use of a laterally directed hydrogen peroxide rocket motor mounted on a station wagon. The use of a rocket motor provides accurate and flexible control of location and magnitude of the input disturbance. Response data taken from these tests are compared with the responses from a computer model utilizing the disturbance equations. These results are applied to illustrate the effects of wind disturbance on vehicle handling.