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In order to properly evaluate the consequences of replacing conventional Otto-cycle engines with alternate power systems, comparisons must be carried out at the vehicle level with functionally equivalent cars. This paper presents the development and application of a procedure for establishing equivalent vehicles. A systematic weight propagation methodology, based on detailed weight breakdowns and influence factors, yields the vehicle weight impacts due to changes in engine weight and power. Performance-matching criteria, utilizing a vehicle simulation program, are then employed to establish Otto-engine-equivalent vehicles, whose characteristics can form the basis for alternative engine evaluations.

This paper on disc brakes for passenger cars with incorporated automatically adjusted handbrake mechanisms traces the way in which the experience with various alternative Girling adjuster systems is leading to recommended design- and development parameters for such devices.

The brakes are applied automatically at the time of any system failure. The parking brake is operated by the parking/emergency switch on the dash panel or the ignition switch, without physical effort as found in the conventional hydraulic brake systems. Full-power parking/emergency brakes and fail-safe concepts have been accomplished in the straight-air brake systems. However, duplication of these systems to hydraulic brake systems incurred some difficulties due to the physical properties of fluid, and it is generally concluded that the parking/emergency brakes must be mechanical brakes, and the hydraulic pressure should not be maintained for extended periods of time. The electro-mechanical method employing a detent system is a breakthrough in restraining spring force during normal operation.

Duhamel's theorem is used to integrate an analytical slab solution with a nodal solution to utilize the advantages of each method. The analytical part of the model provides a detailed temperature distribution through the rotor rims which is used to estimate the rim thermal stresses. Experimental results are used to derive a model of the vent cooling. Brake dynamometer tests are compared to the calculated results to verify the model. Some examples of parameter variations are given that show typical model capabilities.

This paper gives analytical expansion to the possibilities facing a designer when dealing with detail design problems of the Girling Colette caliper. A feature of this caliper is the flexibility with which it can be tuned to encompass the total requirements of the installation.

Our institute, J.A.R I., has built a new wind tunnel to accommodate full-sized vehicles. Various newly developed ideas were incorporated in this facility, which, nearly 100 m long, is of Eiffel type with two test sections arranged lengthwise that can be used simultaneously and efficiently. Wind velocity ranges from 2.5 to 57 m/s in the first test section, which is 3 m (H)x4 m(W)x10 m(L). In the second test section, which is 5 m(H)x6 m(W)x13 m (L), the wind velocity ranges from 1 to 23 m/s. The facility enables a wide range of aerodynamic experiments to be conducted with 1/5 scale models up to full-sized passenger cars in the first test section, as well as with heavy duty trucks and buses in the second test section.

Primary design factors with regard to outside mirrors are curvature, size and spatial localization. Experiments were conducted to find the effects of these factors in relation to visibility and the size of field of view. Investigations to determine visibility requirements were static testing and field testing. The results show that convex mirrors with 47 inch radius of curvature are most preferable for the visibility requirements. Required size of field of view was established taking into account the size of direct field, vehicle size and lateral distance to another car.

The concept of interoperability is based upon standardization of combat vehicles at the subsystem level. Past attempts at international system level development have been frustrated by such factors as a diversity of design philosophy, deployment schedules, production unit cost, and an economic need to maintain commonality with existing national fleets. The logistics potential of common equipment has resulted in renewed interest concerning the use of standardized components. In addition, the heretofore unaddressed area of common crew/equipment interfaces is being investigated. Through careful attention to human factors, a measure of system level standardization may be attained.

Performance and exhaust emissions of five unthrottled open-chamber stratified charge engine designs are compared on an equivalent basis, to illustrate the effects of the different strategies used to mix the fuel and air and to provide data useful for those currently engaged in stratified charge engine development.

The identification of present indicators and controls were tested in several series with 100 subjects having varied demographic backgrounds and their statements evaluated as to the individual technical functions. In tests with another 50 persons, we measured the learning effects as functions of both the individual labels and the various demographic groups. Evaluation of these test series shows the influence of the different demographic data among the persons tested. With 150 subjects tested in European cars the driver's expectations as to where a specific control is located and what specific manipulation he associates with this control was investigated.

A method of working fuel injection engines with stratified charge and prechamber-torch ignition is presented. Ejection effect has been employed for cleaning the prechamber of burnt gases and filling the same with air-fuel mixture of necessary composition. The ejection effect is produced by the fuel jet injected through the prechamber which makes it possible to scavange the prechamber without the use of third valve. Besides, this method provides necessary stratification of charge along the direction of flow of burnt gases out of the prechamber. Investigations carried out on single cylinder research test bench and on experimental multicylinder engine created by modifying the serially produced automotive engine show that the proposed method of working makes it possible to improve the power and economy parameters of the engine with sharp reduction of toxic components in the exhaust gases at the same time.

An Advanced Concept Diesel (ACD) engine, previously evaluated under a U.S. Energy Research and Development Administration contract, was dynamometer tested to provide data for the computer simulation of a diesel passenger car. The car was calculated to have the potential for meeting a 0.25 g/km (0.4 g/mi) NO standard (without cold start) if high EGR rates were introduced. The 0.25 g/km (0.41 g/mi) hydrocarbon standard would not be met by the unmodified vehicle, although use of an advanced transmission was projected to decrease hydrocarbons just to that level. Before the ACD engine is considered further, adequate durability should be demonstrated with high EGR rates, and lower hydrocarbon emissions are needed.

The paper describes the application of a hydraulic pump/motor and a hydro-pneumatic energy-storage as a supplement to the conventional internal combustion engine in a city bus. The resultant hybrid-system makes it possible to smooth out the combustion engine power output and to regenerate the braking-energy which in conventional busses dissipate as heat. Computer-simulation and supplementary experiments with a model-system have shown that, depending on the driving pattern of the bus, this type of hybrid-system would lead to a 10 - 30% fuel saving provided that an appropriate control strategy is used.

This review primarily covers scrap tire disposal processes used, or suggested for use, in the U.S.A. Sufficient statistical data are presented to define the magnitude of the scrap tire disposal problem. The constraints of an ideal solution are presented as a basis for a critical review of current and proposed scrap tire disposal procedures. Our conclusion is that no one scrap tire disposal procedure is so outstanding as to be used exclusively to handle the problem. Geographic location and economics will dictate which scrap tire disposal procedure will be used.

A unique approach has been initiated to involve several universities in a coordinated research effort. Research faculty at selected universities, where research interests relate to major problems of concern to the plastics industry, have been formed into a research team. Their individual research efforts are being coordinated by the Plastics Institute of America. Through constant surveillance by the Institute's Board of Trustees, research objectives are directly related to the needs of industry. “Maximizing the Life Cycle of Plastics” is one of two general research projects currently underway.

The effects accruing from the choice of precious metals and their relative ratios are considered in catalyst systems used in VW and AUDI cars under open loop conditions and dynamic closed loop controlled engine conditions in conjunction with an exhaust gas oxygen sensor. The best catalyst system for three-way activity found when comparing major manufacturer technologies was the system Pt/Rh = 5:1 which is introduced in two 1979 engine families sold in California, VW microbus and Audi 5000. This paper discusses also the interrelationship between window and sensor characteristic and novel emission control concepts including metal supported catalysts and catalysed exhaust pipes for the improvement of warm-up.

The emissions of hydrocarbons (HC) and carbon monoxide (CO) from a vehicle can be decreased by obtaining faster warmup of the catalytic converter. An experimental study of the consequences of effectively internally insulating an exhaust pipe has demonstrated (1) a significant increase in converter-inlet gas temperature during warmup, and (2) a lowering of HC and CO emissions on the Federal Test Procedure by about 15% on one particular vehicle. A mathematical model has been developed and verified to predict converter-inlet temperature histories from known exhaust-takedown temperature histories and to quantify the effects of various insulation material properties on the temperature of the gas entering the converter. The dangers of drawing misleading conclusions from tests of exhaust pipe insulation are discussed.

AM General and the main producer of articulated buses in Europe, M.A.N., have jointly introduced this type of bus to the U.S. market. The bus was modified from its originally European configuration to comply with all U.S. regulations and specific customer requirements. Description of the bus and its components are presented in detail emphasizing the specific aspects of an articulated bus--the underfloor drive train, articulation joint and braking system. The structure, electrical system, interior and air-conditioning system are also outlined.

An experimental system has been constructed to study the heat transfer processes in the straight section of the exhaust port of a four-stroke, spark ignition engine. The effects of engine variables on the steady-state heat transfer rates have been studied at four locations in the exhaust port. It was found that the heat transfer rates have a significant dependence upon the location within the exhaust port. Data have been correlated in the form of a Nusselt-Reynolds number relationship for local and spatially averaged steady-state heat transfer. It has been shown that the use of conventional steady-state heat transfer relationships for developing steady-state turbulent flow in pipes predicts heat transfer rates which are lower than those experimentally observed.

This paper discusses the relation between the exhaust gas temperature and the engine parameters. The engine speed, load, spark timing, air fuel ratio and exhaust gas recirculation ratio were chosen for the calibration parameters, and the compression ratio, valve overlap timing, engine displacement, the number of cylinders and others were chosen for the design parameters. A series of tests were done on six different engines. The data were analyzed statistically and the experimental equation was derived with which the exhaust gas temperature can be estimated. The paper includes the process of the analysis and some application of it.