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Most automotive piston engines employ a front-mounted, belt-driven coolant circulation pump. The pump shaft is normally supported by a double row rolling-element radial contact bearing. The engineering analysis for an improved method of water pump bearing service load and life prediction is described here. This general analysis considers most of the design variations which are found among engines, water pumps, and bearings in current use. A rather thorough accounting has been made here of the various sources of bearing loading occurring in this application. Bearing life is determined according to the recently revised A.F.B.M.A. standards.

The temperature history at a location in the combustion chamber of a spark ignition (SI) engine is determined by using the intensity of radiation from the recombination continuum CO + O ↠ CO2 + hv. The flame was initiated separately at two locations in the combustion chamber while the radiation was monitored at one location thereby making the arrangement somewhat equivalent to monitoring the radiation from two different gas zones in the chamber. Agreement between the predicted temperature history with heat transfer and the experimental temperature measurements was found to be good around the stoichiometric region but large differences were noticed when the engine was run at lean mixture strengths.

A suite of computer programs has been developed for the analysis of loading and lubrication characteristics of rotor bearings and main bearings in the rotary engine. The lubrication analysis was very similar to that for reciprocating engines and required only very slight modification.

A fleet of 64 heavy-duty 1970-71 model trucks and buses powered by a variety of diesel engines were tested periodically to determine exhaust smoke behavior. Smoke tests were made when the vehicle was new or nearly new and at four month intervals thereafter, or until 160,934 km (100,000 miles) odometer reading was reached. Gaseous emissions of hydrocarbon (HC), carbon monoxide (CO), and nitric oxide (NO) were measured at one point early in the project. Both smoke and gaseous emission tests were performed with chassis versions of the engine dynamometer Federal Test Procedures (FTP). Results in terms of “a” (acceleration), “b” (lugging), and “c” (peak) smoke factors versus mileage are reported for the 13 engine-vehicle-application groupings.

The Ford Auto/Emission Driver System automates the driving of a test vehicle on a chassis dynamometer while it is undergoing exhaust emissions testing. The system “drives” the vehicle through the 1372 s EPA Urban Dynamometer Driving Schedule associated with the CVS-C and CVS-CH Test Procedures by applying the accelerator and brake pedals directly and also shifts the transmission if the vehicle is equipped with a standard transmission. The Ford Auto/Emission Driver System consists of a hybrid analog and digital electronic control console including a magnetic tape recorder and a servo hydraulic mechanical console linked to universal interface fixtures in the vehicle via flexible mechanical push-pull cables. The high response hydraulic rams are mounted remote from the vehicle to permit design of actuating fixtures which are compact, light weight and therefore easy to install.

This paper describes a new, closed-loop programming system which faithfully transfers road operation to the chassis dynamometer. The system provides stable, rapid, accurate response to programmed speed and throttle position changes. Using a derivative of a torque-related signal, changes in power train performance are compensated realistically by electronic modification of either throttle or speed signals as a function of part or wide open throttle command. Under conditions of minor power loss, part throttle compensation is found to restore such uncontrolled parameters as engine speed and driveline torque to the values measured without engine degradation.

This report describes the results of a surveillance study initiated by the U.S. Environmental Protection Agency to measure gaseous exhaust emissions from 1020 light-duty motor vehicles. This project was the second effort in a continuing program using the CVS Federal Test Procedure. Selected privately-owned vehicles, drawn randomly from six metropolitan areas, were tested in as-received condition. The emissions data obtained from these 1966-1972 model-year vehicles are reported in grams per mile of unburned hydrocarbons, carbon monoxide, carbon dioxide and oxides of nitrogen while fuel economy is reported in mpg as determined over the Federal Driving Schedule.

Methanol's potential as a gasoline extender has been evaluated, with data being obtained in the areas of fuel economy, exhaust emissions, and driveability. The results of tests with three cars, having carburetion spanning the range normally encountered in the existing car population, showed that methanol's effect on fuel economy and emissions could be directly related to its leaning effect on carburetion. The data suggest that any benefits in these two areas would only be significant for older, rich-operating cars. A 13-car driveability study indicated that the large increase in fuel volatility which occurs with the addition of methanol to gasoline could pose serious problems. A marked increase in vapor locking tendency was observed when no front-end volatility adjustments were made to the methanol blends. Stretchiness, a lack of expected response to throttle movement, was also found with the methanol blends.

Methods are discussed for obtaining in-service loads, motions, and operational parameters on customer-operated vehicles. Special load measuring transducers and unique unattended monitor recorders were utilized. Some statistics associated with selection of field customers are discussed.

This paper discusses the design requirements and operation of two onboard, self-contained, level histogram recording devices that can operate unattended for six months and store data in a removable digital memory. The paper describes the types of data the units record, data sampling and recording techniques, and memory data interrogation procedures.

A servohydraulic test center for the automobile industry is described in this paper. Mechanical, hydraulic, and electronic modular components are assembled for all-purpose test facilities. The fundamental structure of a controlled system with a cylinder-servovalve combination is explained. Some measurements and the quality of the reproducibility of the simulation of random loads encountered in road testing are discussed for two special test stands for axles and driveshafts.

This paper deals with the overall program of vehicle field data collection and instrumentation. In it, the philosophy of the vehicle durability test is discussed relative to the requirement of accurately duplicating customer usage. Advantages and disadvantages of various data collection methods are also discussed. A brief, nonrigorous discussion of data analysis is included.

One of the more important aspects of vehicle design is mechanical mobility. This term is a measure of how fast a vehicle can get from point A to point B without breaking while preserving the cargo and driver comfort. The road simulator has been used extensively as a laboratory tool to determine the durability aspect of the mechanical mobility problem. The objective of this paper is to show how the road simulator is used to provide the engineer with a validated mathematical model which he can then use to perform a parametric study to improve ride comfort. Specific areas of discussion are: mathematical model verification; correlation of model and simulator data; parameter adjustment to obtain improved ride. As a result of this study, the design engineer has a more precise vehicle model than has been available, and the test engineer has a verified laboratory simulation technique for vertical dynamic terrain inputs.

More meaningful laboratory testing can be achieved from test programs designed to better simulate the usage of the component or system in the hands of the consumer. Steering gears and linkages are adaptable to force measurement during vehicle operation. This data can then be used to program laboratory test equipment in a manner which simulates the force environment encountered in vehicle usage.

The intent of this study is to present effectual methodologies concerning single-phase and two-phase mixing problems which may conveniently be utilized by a design or developmental engineer. In particular, for single phase, turbulent, compressible coaxial fuel and air mixing problems, an index is presented which provides a sensitive indicator for determination of the degree of mixing in a given mixing chamber. Working graphs for several hydrocarbon fuel and air stream combinations are used to demonstrate the utility of the index. In addition, the index is shown to be of value for studying twophase mixing such as occurring in automotive carburetors. This paper further demonstrates the utility of the hydraulic analogy for studying complex mixing problems such as commonly occurring in automotive carburetors and manifolds, gas turbine combustors, and simple mixing chambers.

Many techniques are currently being used for different types of road simulation studies. These approaches vary from using a road simulator as an analysis tool for fatigue to durability simulation to predict the life of a complete vehicle in the laboratory. Different inputs to vehicles have been used, from the apparent straightforward approach of vertical inputs through the tire to complete simulation of combined loads through multiple inputs into the vehicle. An overview of these techniques developed over the past decade is presented. The analysis relates to the techniques and application of test equipment and methods of testing rather than the prediction or classification of actual results.

The purpose of this study was to obtain information useful for improving crash protection for small children. Previous research efforts have produced findings relating to accident characteristics in general, and those findings have been used to improve passenger protection. However, little work has focused on the particular characteristics of nonfatal and fatal accidents involving small-child passengers. Thus, this study compared accidents involving small children (five years old and younger) with accidents not involving small children, to establish the similarities and differences between those types of accidents. The principal findings of the study are briefly summarized in the following description of a composite accident in which a small child is an occupant of the car: The child is very likely a passenger in a car driven by a female between 20 and 35 years of age, who is not wearing a seat belt, and who has not been drinking.

In late 1971, Alderson Research Laboratories initiated the development of a totally new design for a similar pair of crash-test dummies in the three-year-old and six-year-old child sizes. The fundamental basis for this design was a compilation of recent child anthropometry surveys which served to define overall body weights and to target key external dimensions. Models built to conform to these targets were used to derive standards empirically for weight distribution and segment centers of gravity. These data are presented along with a description of the mechanics by which the sculptor's art, the anatomist's knowledge, and the machine designer's skills were blended to effect the transformation into the final human simulation models.

This paper presents the anatomical considerations and general principles of occupant restraint in the car crash environment with emphasis on the protection of the child auto occupant. Design criteria and typical performance problem areas in child restraint systems are discussed.

This paper discusses the overall concept and philosophy of field data acquisition and evaluation, incorporating results from an industrial tractor component. Since the scope of the subject is so large, the major part of the discussion is centered on the method of analyzing the data and life prediction. Some methods may or may not conflict with current procedures, and are presented as only one method of evaluation.