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Experimental Brake Specific Fuel Consumption (BSFC) data are presented for two engines as a function of engine speed, load, outlet coolant temperature and inlet oil temperature. The engines used in the study were the Cummins VT-903 (turbocharged) and the Caterpillar 3208, both being direct-injection and four-cycle. The data were taken for the Cat 3208 engine using a fractional factorial statistical method which reduced the total test matrix from 256 to 64 data points. The experimental data are used in the development of BSFC regression equations as a function of load, speed, outlet coolant temperature and inlet oil temperatures. A mathematical parameter for expressing quantitatively the change of BSFC per 10°F change in coolant and oil temperature is presented. It was found that an increase in the coolant and/or oil temperatures had the effect of reducing BSFC in both engines.

This investigation dealt with the experimental determination of a select chemical specie - the hydroxyl radical - present in the non-flamed end gases ahead of the flame front in a spark-ignited engine operating under conditions of both normal and knocking combustion. Concentration measurements of the hydroxyl radical present in the end gases were obtained with the technique of resonance absorption spectroscopy utilizing a broadband-output, frequency-tunable, flashlamp-pumped, organic-dye laser. The dye laser and a photographic spectrometer were placed on opposite sides of a single cylinder research engine and the combustion chamber of the engine was fitted with quartz windows that allowed the dye-laser light pulse to pass through the end gas region and into the spectrometer. The dye laser was pulsed once at a present crankangle during the combustion cycle recording the 2∑+-2∏ electronic transition absorption spectrum on film.

The State-Of-The-Art of automotive corrosion testing is reviewed with particular emphasis on testing related to the exterior environment. The generally poor correlation of laboratory tests with field performance is reviewed and the factors affecting both laboratory and field tests are discussed. Recommendations for the conduct of field tests are presented.

A brief review of the basic theory of the electrochemical corrosion of metals is presented, with emphasis given to the mixed-potential theory. Currently accepted electrochemical corrosion mechanisms of several major forms of corrosion are reviewed. Galvanic, crevice and pitting types of corrosion are considered. The presently held theories on the atmospheric corrosion of steel is also discussed.

Typical automotive finishing practices are described with emphasis on paint system capabilities and limitations that affect painted part corrosion resistance. Limitations of each finishing step are reviewed along with suggestions for suitable part design to overcome system deficiencies.

Ontario upholds a high level of maintenance service on its highways during the winter months. The majority of these roads are maintained to bare pavement condition, while others are maintained to center bare condition. This paper describes the methods used to obtain this level of service under various winter conditions. Recently, environmentalists have expressed their concern over the effects of salt used for winter maintenance on the environment. In response to this concern, Ontario has begun a research program to evaluate the effect of salt on the environment, and to find techniques for reducing the amount of salt used, while still providing the current level of service to the public.

An overview of the principal factors involved in the initiation and propagation of the corrosion of painted steel is presented. One of the major protective functions of the paint system is to act as a barrier to electrolyte; corrosion begins at sites where penetration of electrolyte has occurred. Loss of paint adhesion, caused in most cases by cathodically produced alkali, results in the spread of corrosion. Improved corrosion protection can be obtained by use of alkali-resistant paint binder resins. Corrosion inhibitive pigments can improve performance by slowing the overall corrosion rate; conversion coatings can slow the lateral spread of alkali attack.

The interaction of our natural elements such as rain, snow and humidity, with chemicals introduced to the environment, provides a complex chemistry which is one of the most corrosive in North America. The chemistry of this environment and its relevancy to automotive corrosion, forms the basis of this paper. An understanding of this chemistry is necessary in order to conduct meaningful corrosion tests and reduce degradation of automobiles.

This paper presents the state of the art on the selection and use of de-icing chemicals and abrasives. More specifically, it deals with: the need for de-icing chemicals and abrasives, problems associated with them, alternative solutions, factors to consider when selecting the appropriate solution, the current practice, and the future trends in the use of chemicals. Based on a recent literature survey, the author concludes, that, even though we are on the verge of a breakthrough, until the time comes, we should be prepared to live with these chemicals for many years, and that the adverse effects due to chemical use can be minimized through the combined efforts of road and automotive engineers, especially through the application of existing knowledge.

Computer-aided crash reconstruction has become common-place in the automotive safety profession, primarily because of widespread distribution of software under public auspices. The SMAC (Simulation Model of Automobile Collisions) program, for instance, is available through NHTSA at nominal cost. This paper exhibits some of the limitations and strengths of accident reconstruction simulations, with illustrations and emphasis drawn from the SMAC program. In particular, some coarse physical approximations used and some coding errors incurred in the formulation of SMAC are discussed, together with their respective effects on the accuracy of prediction. Revisions of the basic SMAC coding have been developed at BYU to overcome these shortcomings. Results of uncorrected and revised SMAC simulations are demonstrated by comparison with the physical theory. Comments regarding a new SMAC program just completed under U.S. Government contract are presented where appropriate.

The front end of a standard factory model passenger automobile was modified at those points with the greatest potential for inducing injuries for the purpose of reducing the primary impact of a pedestrian against the car. The modifications were performed on the geometry and the structure of the front end. Special consideration was placed on achieving a suitable design. In experimental investigations with adult and child pedestrians, loads inflicted on the bodily parts struck by standard factory model and by modified vehicles were measured and compared. It was discovered that considerable reduction of the loading was achieved with the modified vehicle upon primary impact.

Detailed investigations of automobile crashes in which children under 10 years old were passengers were carried out. The purpose of this study was to investigate the injury patterns of restrained and unrestrained children and to assess the performance of child restraint systems in real world crashes. Crashes which occurred mainly in Washtenaw and Oakland counties of the state of Michigan were surveyed. A total of 348 vehicle crashes involving 494 children less than 10 years old were identified. Forty eight crashes involving 63 children were selected for in-depth investigation. 37% of the children in the investigated cases were restrained by an adult lap belt or a child restraint. It was found that only 4.7% of the children in the overall sample were restrained. Both adult seat belts and child restraints (when used) were found to be effective in reducing injuries in crashes. Head and facial injuries were found to be the most common form of injury to children.

Current design of seat belt systems may provide insufficient protection for the car occupant. Thus occupants may sustain head injuries due to large head excursion. Chest injuries may occur due to unfavourable restraining geometry or excessive belt slack. Finally, spinal injuries may appear due to high vertical loads on the body. Using basic criteria of favourable biomechanical restraining, design improvements of a conventional three-point seat belt system are proposed. It is shown that the design of the seat is of great importance to the biomechanical protective effect of the seat belt. A simple redesign of a conventional seat is proposed. Comparative sled tests with a new seat design and with a conventional seat are performed. The effects of a webbing-locking B-pillar loop and of an automatic belt tightener are also studied. The results show that significant improvements can be obtained by simple means.

Child restraint performance in frontal and lateral crash simulations is presented and discussed based upon tests conducted on the Calspan HYGE acceleration sled. Differing acceleration pulses for frontal tests were used to evaluate the pulse shape effect upon the child restraint systems. Two types of three year old size ATDs were used and restraint systems were intentionally improperly installed in an effort to ascertain the potential hazard to the child occupant from improper installation. Data obtained include head excursion, head and chest triaxial accelerations, HSI and CSI values for the ATDs. High speed movie coverage produced dummy kinematic results. Results of the study allow comparisons between the effects of different pulse shapes and the effects of different ATDs on restraint performance and comparisons in dynamic performance of the ATD/restraint complex under both proper and improper system installation.

Side impact accidents are the most severe and second frequent traffic accident configuration. By a comparison of results of tests with and without intrusion, this paper shows that the severity of side impact for the occupant seated near the impacted side is mainly due to intrusion of the side wall inside the car compartment of the struck car. Without intrusion, injury criteria recorded on a dummy are much lower than when there is intrusion. The influence of intrusion can be explained by the deformation speed of the side wall of the struck car. The velocity change of different parts of cars and of dummy have been determined in two tests conducted at 40 and 50 Kph. The diagrams of these velocity changes indicate that the door and the frame seat of the struck car sustain a velocity change higher than the car floor. The pelvis of the dummy seated near the impacted side sustains a velocity change in the same order of magnitude as the door, whereas its chest has a lower velocity change.

A comparative study of the safety performance of asymmetric and standard HPR windshields was conducted. The effect of increased interlayer thickness was also quantified. There were four different types of asymmetric windshields which had inner layer thicknesses of 0.8 to 1.5 mm and interlayer thicknesses of 0.76 and 1.14 mm. The experimental program consisted of both full scale sled tests and headform drop tests. A total of 127 vehicular impacts were carried out using a modified Volkswagen Rabbit. The test subject was a 50th percentile Fart 572 anthropomorphic test device. The asymmetric windshields were found to have a lower lacerative potential than that of the standard windshield. The best TLI value of 5.2 was provided by a 0.8 - 0.76 mm windshield at 60 km/h. That for the standard windshield was 7.7 at the same speed. All HIC values were less than 1,000 at 48 km/h.

This paper describes the results of a 2 year study into the field accident performances of two basic designs of energy-absorbing steering assemblies. The two basic designs are the axial-collapse type of steering column used in conjunction with a shear capsule and the self-aligning energy-absorbing steering wheel mounted on a nonstroking column. The study identifies major injury causation factors for these two types of steering assemblies. The analysis was performed on 161 accident cases selected for unrestrained drivers in frontal accidents in two vehicle types.

Fuel economy degrades significantly as ambient temperature decreases. Diesel, stratified charge, lean burn and turbocharged-knock-limited engined automobiles show significantly less degrdation in fuel economy and emissions than do conventionally-carbureted, catalyst-equipped automobiles. In particular, the new diesel automobiles offer large benefits in weight-normalized fuel economy and emissions for the wide temperature range found in Canada's climate.

Comparison of vehicle thermal efficiency and engine load factor for 1977 and 1978 model year certification vehicles shows low correlation. At any load factor, the spread in thermal efficiencies was on the order of 2 to 1. These facts suggest that, with existing technologies, vehicle manufacturers can realize a significant improvement in fuel economy through better matching of engines (specific fuel consumption), transmissions and final drive ratios to vehicle power requirements.