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FUNDAMENTAL considerations, primarily of an aerodynamic nature, that are involved in the design of the turbine component of the gas turbine engine, are discussed by the author. He has achieved a practical outline on a basic level by limiting his material to the general techniques that will be of immediate interest to the turbine designer. He first discusses the fixed design conditions concerning temperatures and pressures, and then divides the design problem into two parts: 1. Determination of the velocity diagrams. 2. Design of the blade profiles to yield those velocity diagrams. The discussion of the second part of the problem includes the evaluation of four types of the most commonly accepted profile design methods. He then points out that aerodynamics, stress, mechanics, fabrication, and assembly must all be considered together to achieve the best possible design of the turbine.

The increasing levels of affluence in the highly industrialized western societies have resulted in a drastic and increasing deterioration of the quality of man's environment. The economic facts in these societies are such that it actually “pays to pollute.” Air and water pollution, solid waste disposal, and noise pollution have become areas of major concern for the institutions of higher learning. Through instruction and research, knowledge toward the alleviation and control of environmental pollution must be disseminated and advanced. One of the major contributors to the present state of environmental deterioration is the almost absolute lack of well-defined control criteria. Much needs to be done in this area and the academic community has the know-how and economic remoteness to tackle this problem. One of the most fascinating facets of the environmental pollution problem is its interdisciplinary nature.

Introducing the direct study of environmental problems into university courses seems too difficult. The only practical way of alerting future engineers to their responsibility in considering the effect of their activities on the environment is indirectly. The development of courses in instrumentation and the use of experimental equipment are effective and do not require substantial modification of an engineering cirriculum. The intention of this paper is to describe certain experimental work to illustrate their use in the field of environmental problems.

The roles and responsibilities in this era of technological morality raise questions concerning active participation of engineers in ordinary day-to-day problems. Items of current interest, such as waste disposal, summer “brownouts,” locations of powerplants and their possible detrimental effects on ecology, are discussed; the feasibility of providing qualified group judgment on national policy is shown; the ways and means of publicizing the overall problems are presented.

The paper discusses two general definitions of adaptive control in an attempt to determine whether adaptive controls can effectively be employed in low-cost, high-quality auto production. Uses of adaptive control in various industries are described. Future applications are suggested in auto manufacture. Solid-state circuitry and computer control are major areas of such adaptive control application which are explored.

In view of impending changes in the British Standard concerned with ignition interference, to conform with the recent International Agreement (E.C.E. Regulation No. 10) and the probable corresponding amendment to the United Kingdom legislation, a series of road-side measurements of ignition interference radiation has been made on more than 10,000 vehicles. From the known suppression arrangements currently used on the vehicles measured, the results have been analysed as to their efficacy in relation to present United Kingdom legislation and the E.C.E. International Regulation; reference is also made to the SAE Standard J.551a and b. The effects of multisource ignition interference resulting from areas of high density traffic on the reception of VHF frequency-modulated radio and VHF positive-modulation TV signals are described.

Low Profile glass reinforced polyester Bulk Molding Compounds (BMC) and Sheet Molding Compounds (SMC) offer the automotive engineer two classes of materials with desirable properties for painted outside body parts. This paper compares methods of manufacture, molding parameters, and properties of BMC and SMC. Several applications are analyzed and reasons for material selection discussed.

The paper discusses the SAE Technical Program on RFI Measurements and is basically a tutorial review of radio frequency interference/electromagnetic interference (RFI/EMI) measurements on automobiles. The text is designed to provide engineers and technicians not familiar with RFI/EMI measurements with a basic appreciation of the measurements, the terminology used, the reasons for measurements, and how measured data should be presented. SAE Standard J551a is discussed. Given are background and data on basic descriptions of EMI and its effects on the environment; the basic history of electric field measurements and antennas; characteristics of receivers-including descriptions of heterodyning, mixing, peak detection, average detection, and quasi-peak detection-and a brief history of EMI receivers.

There has been a steady growth in the use of plastics due to better understanding of its performance, advantages, and limitations. Since 1960, reinforced plastics have played a greater role in the automotive industry in exterior applications. This paper explores the development and uses of glassfiber reinforced thermoplastics and glassfiber reinforced polyesters. Although many of the problems of these reinforced plastics have been solved, many refinements are needed; however, with these refinements, the use of reinforced plastics in the automotive industry will substantially increase by 1975, and thereafter.

The simulation described in this paper is intended to provide a flexible and economical tool for designing and evaluating inflatable safety restraints. It should be useful both for parameter studies and as a supplement to experiment. This two-dimensional digital simulation is now being completed as part of the CAL/AMA Two-Dimensional Crash Victim Simulation. This paper discusses the assumptions made to formulate the model, sketches the simulation organization, and outlines the three major submodels-thermodynamics, bag shape, and restraint forces.

Nickel-copper alloys, marketed under the name Monel, have been found to be extremely active NOx reduction catalysts. At temperatures above 1300 F, and under net reducing conditions, Monel will catalyze the removal of 90% or more of the NO in automotive exhaust at space velocities of up to 100,000 v/v/hr. On unleaded fuel, Monel catalysts have shown good activity maintenance in mileage accumulation runs as long as 31,000 miles. Catalyst life is limited by physical deterioration of the catalyst which causes increases in exhaust back pressure. On unleaded fuel, Monel in its present form will last approximately 10,000 miles at 1700 F (∼60 mph) before back pressure begins to rise rapidly. The presence of lead in the fuel substantially increases the rate of Monel deterioration. When Monel is used as part of a dual-bed catalyst system two problems, which appear to be generic to dual-bed catalyst systems, arise.

Exhaust gas recirculation (EGR) was found to be an effective means of reducing automotive NOx levels with no major unsolvable problems over 52,000 miles under city/suburban driving conditions. Compatible with air injection and engine modification systems for HC and CO control, EGR effectively reduced the NOx levels with no decrease in reduction over the 52,000 miles. Engine wear and engine cleanliness with EGR was normal for the mileage and driving regime. However, the throttle area and exhaust valves were found to be sensitive to leaded fuels.

A single-cylinder research engine was operated on pure hydrocarbons (HC) and simple mixtures of pure hydrocarbons to study the effect of fuel composition, equivalence ratio, and mixture temperature on exhaust emissions. Used as fuel components were hydrocarbons-n-pentane, 2-methyl-2-butene, isooctane, and m-xylene. Total hydrocarbon emission in terms of moles of exhaust HC/mole of fuel input was lowered by increasing the amount of xylene in the fuel when operating on the fuel-rich side of stoichiometric; total hydrocarbon emission was higher for higher aromatic fuels when air-fuel ratios approached the lean misfire limit; the effect of mixture temperature on hydrocarbon emission was insignificant. 1-Methyl-3-ethylbenzene was observed as a synthesis product of combustion in the exhaust from fuels containing m-xylene. With increasing m-xylene concentration in the fuel, the yield of 1-methyl-3-ethylbenzene increases, reaches a maximum, and then decreases.

THE high torque multiplication converter is particularly applicable to city-bus service because it provides the good acceleration that is so important in this field. This type of converter has also been used advantageously in tractor and industrial service. In this connection, the author presents curves to illustrate some of the converter characteristics that must be considered in the design and application of torque converters.

IN discussing the transition from torque converter to fluid coupling operation. the author explains that the point where the transition should be made and the performance range that should be favored depends on the type of service required of the vehicle. For example, he says that a good coupling range is important in passenger cars, where a good deal of the operation is at part load, whereas in city buses, maximum torque multiplication is more important to give the high acceleration expected of these heavy vehicles.

THE losses that occur in torque converters are of two types: flow losses and shock losses. The causes of these losses and how they are minimized in the polyphase converter are discussed in this paper.