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This paper summarizes the highlights of developments of the rotating combustion (RC) engine at Curtiss-Wright Corp. in each of several principal areas; speculates on remaining directions, both within and without the framework of previous explorations; and briefly describes germane technical features of the engines used in commercial applications of other licensees. At the same time an attempt has been made to span gaps left by previous papers or publications and to expand material considered proprietary earlier. Design features, testing, and ramifications of the RC1-60 rig engine are examined in detail. The application of the fundamentals and principles of the RC engine to automotive, air-craft, and small, air-cooled engines is also described.

The Inter-Industry Emission Control (IIEC) Program included the thermal reactor as one of the effective ways of oxidizing HC and CO in the exhaust system. However, this was accompanied by very substantial fuel economy penalties, especially in the case of small engine-low emission concept vehicles. Starting with a new concept aimed at obtaining the HC/CO oxidizing trigger temperature in the thermal reactor by modifying engine settings, the authors arrived at an economical technique of matching the thermal reactor to the engine.

During the past four years, Mitsubishi Motors Corporation has been active in the design and development of catalytic converter systems in the IIEC Program. Experience indicates that an effective dual catalytic converter, consisting of a NOx catalyst and a HC/CO catalyst, is indispensable to achieve the stringent IIEC targets, established on the basis of 1976 Federal Standards. However, there still remains a major difficulty of meeting the NOx target since NO is regenerated in the HC/CO catalyst in the dual converter system. This paper describes our major efforts in seeking a breakthrough to control the NOx emission, and covers some noteworthy findings on transient NO concentrations at the inlet and outlet of HC/CO converter in an experimental dual converter.

A test procedure to determine the conversion performance of oxidation and reduction catalysts for the treatment of automotive engine exhaust gases is described. The variable parameters are the air/fuel ratio, the secondary air quantity and the space velocity. The results are recorded in diagrams which permit the selection of optimal catalysts with reference to the conversion and which also form the basis for the lay-out of the necessary devices for controlling air/fuel ratio and secondary air. Characteristic results with noble metal catalysts on monolithic supports and pelleted base metal catalysts are shown.

During vehicle cold start, emissions, mass flow rates, and catalytic converter space velocities vary by orders of magnitude. Therefore, catalytic exhaust control systems must be designed to operate at high efficiency almost from the moment of engine start-up. Catalysts must reach their operating temperature as quickly as possible. Therefore, the utility of different methods for improving the warm-up characteristics of catalytic systems is illustrated. A very elegant method to speed the warm-up is the use of the engine itself as a “preheater” for the catalytic converters. High exhaust gas enthalpy to raise exhaust system mass up to its operating temperature is obtained by the use of extreme spark retard, stochiometric mixtures, and fully opened throttle. Intensive studies to investigate the effects of concurrent changes of spark timing and air/fuel mixtures on exhaust gas temperature, enthalpy, NOx and HC emissions are discussed.

New glass-reinforced thermoplastic foam resins have been developed that can be molded on conventional screw injection molding machines. The glass reinforcement of the thermoplastic foams results in the restoration of physical properties normally lost when unreinforced thermoplastics are foamed.

The 1975 federal CVS test procedure and emission standards have placed a heavy emphasis on minimizing the time required after engine start up to begin converting exhaust emissions. Four major improvements in catalytic HC/CO converters have been made in the past year to reduce catalyst ignition time: 1. Use of low thermal capacity monolithic catalyst supports. 2. Locating converter after thermal reactor and/or closer to the exhaust manifold. 3. Development of catalysts with superior stability to long exposure at high temperatures. 4. Development of catalysts with improved low temperature activity. Small laboratory samples of potential HC/CO oxidation catalysts were screened for activity in a “laboratory simulated cold-start” test with exhaust from a 2-cyl engine. Several improved catalyst candidates were evaluated in a full-size converter “cold-start” test with exhaust from a 351 in3 engine.

IIEC efforts to develop NOx catalysts with improved durability have continued. Properties of several nickel oxide catalysts on pelleted, monolithic ceramic, and metallic supports are discussed and the engineering requirements for their effective use are defined. Some promoted nickel oxide, pelleted catalysts show good low-temperature activity, and produce minimal amounts of ammonia but are strongly deactivated by sulfur in the feed gas. Monolithic and metallic catalysts, on the other hand, although not active at temperatures below 1000 F, are very active at higher temperatures where deactivation by sulfur and ammonia formation are not troublesome.

Expanded ABS, a terpolymer of acrylonitrile-butadiene-styrene, is discussed in this paper. The physical properties of this material are described, particularly with respect to furniture production. The expansion casting process is described, casting recommendations presented, and equipment detailed. Design and finishing are explored in some detail, and comparisons with wood and other furniture materials are offered.

The Chrysler Corporation made use of a thermosetting polyester sheet-molding-compound (SMC) to provide an efficient, neat-appearing, and economical station wagon air deflector for its 1969 full-size station wagons. This marked Chrysler's first usage of this material for a major automotive body component.

A door side-impact reinforcement beam has been developed that allows efficient use of material in resisting side crush loads. The beam section can be roll formed, thus permitting further economies in fabrication. Analytical techniques have been developed that evaluate and handle bending, buckling, and crippling in beam design. This paper covers the development that led up to these results and includes a detailed description of how to apply the analytical methods.

The status of Toyota's development of low emission concept packages- 1. NOx and HC/CO Catalytic Converter and EGR, 2. Thermal Reactor, NOx and HC/CO Catalytic Converter and EGR and their components is described. Variations of thermal reactor design, performance and durability characteristics are discussed. Above the throttle valve entry EGR has been found to have desirable flow characteristics with a simple control system. EGR rate over 15% brings about unacceptably poor driveability and fuel economy with smaller vehicles. Many types of catalytic converters for pelleted catalysts have been designed and examined for their performance and durability. A down-flow type converter has relatively good flow distribution and warm-up characteristics. As for HC and CO, a few prototype vehicles have met the 1975 Federal Regulation at low mileage, but the 1976 regulation for NOx of 0.4 gm.

Evaluations of aluminum foams show they can be efficient energy absorbers. They are especially interesting because they have virtually no rebounding characteristics. The load-compression response characteristics of the foam can be controlled by variations of alloy composition and foam density, thereby controlling foam strength and ductility. This makes foamed metals attractive candidates for a number of automotive energy-absorption applications. The energy-absorption properties of a number of aluminum alloy foams have been studied under low and medium speed impact, up to 25 mph. The foam density, volume, and size required for a 5 mph “single shot” impact shock absorber have been determined for two automotive weight classes. Nonshearing, columnar, high-density foam structures have been developed to withstand basal compressive loads. These columns have potential for multi-impact shock-absorbing applications.

Recent vehicle durability experience with low emission concept hardware systems is described. The low-emission concept systems discussed include: thermal reactor only, a combined thermal reactor and HC/CO monolithic catalyst system, and a system combining low thermal inertia exhaust manifolds with dual-bed (NOx and HC/CO) catalytic converters. Problems shown to influence either emission performance or vehicle function during both atypical and normal vehicle operation include: the melting of monolithic structures used to support both the NOx and the HC/CO catalytic promoters, the deleterious effect of the sulfur content of gasoline on the performance of pelleted NOx catalysts, and the loss of emission control with malfunctioning engine components. Vehicle fuel economy and performance losses with these types of systems is documented. Current redesign efforts on these low emission concept vehicle systems in an attempt to overcome the durability problems are described.

The work reported has been done in the last year as part of Fiat's collaboration with the Inter-Industry Emission Control Program. Emission results obtained on two concept cars are shown, including respectively: thermal reactor, exhaust gas recirculation (EGR), HC/CO catalytic converter, and NOx and HC/CO catalytic converters. Work is also reported on screening of materials for thermal reactors and catalysts.

This paper describes the extensive effort and progress made by the Toyo Kogyo Company in developing emission control systems applicable to small vehicles with small displacement reciprocating engines, in order to achieve the very stringent targets established by the IIEC program. Three concept emission package systems have been selected as showing promise to achieve the targets, and these packages have been under evaluation for emission performance and durability in the total vehicle systems, which were experimentally built. These package systems incorporate component systems such as thermal reactors, EGR, catalytic converters, and other subcomponents to assist these main component systems. Despite the effort made to date, none of these package systems have reached the stage of satisfying the HC/CO targets over extended vehicle mileage, or the NOx target, even at zero vehicle miles. The durability of these package systems has been revealed as unsatisfactory.

In describing the electronic lamp monitoring system developed at Packard Electric Div. of General Motors Corp., this paper discusses the requirements of lamp monitoring systems, presents a brief history of such systems at Packard Electric, explains how the system functions, and details the method of assembling the system into General Motors automobiles. The requirements for a lamp monitoring system are: it should be able to monitor all types of exterior lamps on the automobile, and the number of lamps must not be critical to design; it must be easy to assemble; it should be simple in design so that it can be repaired in the field with minimum training of personnel; it must be reliable and able to withstand the electrical and environmental conditions to which the vehicle is subjected; there should be minimal change from one car line to another and from one model year to another; and most importantly, the unit cost should be reasonable.

A presentation of potential solutions for detecting and indicating failed exterior automotive running lamps is provided. Comments and summaries of research in the areas of reed switches, photocells, magnetics, and electronic devices are given. Basic design specifications are established along with the posing of other significant system design criteria that must be resolved by automotive companies or safety requirements. The electromagnetically actuated reed switch best satisfies the design requirements for a stable, economical, and usable system. Comprehensive theoretical reed relay systems are presented and their impact on the automotive electrical system is discussed.

Maintenance expenses when using leaded and nonleaded gasolines are reported from a 5-year program encompassing over 10 million miles of operation by 64 matched pairs of employee-owned cars. The data are analyzed on a fuel-related basis for those items of maintenance that might be expected to be affected by the presence or absence of lead antiknocks. Year-by-year breakdowns of important costs are presented. To provide additional information on car operating costs, total maintenance and tire replacement costs are also included. Comparisons are made with previously reported information, and projections regarding the significance of these costs are made for the future.