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Hydrogen is one of the better fuels for use in fuel cells. In the production of hydrogen by reacting hydrocarbons with steam, large quantities of CO must be converted to hydrogen by the classical water-gas shift reaction. Newer catalysts operating at low temperatures offer certain advantages over “conventional” catalysts. Several applications, are discussed, illustrating the advantages of the low-temperature CO conversion catalyst (400 F and higher).

An experimental investigation of the ignition of JP-5 and air mixtures by platinum catalysts has been made using sectional and large-scale ramjet engine baffle combustors. Ignition delay data are presented for combustion chamber static pressures of 0.5–9.0 atm, inlet air total temperatures of 580–1280 F, and fuel-air ratios of 0.007–0.09. A thermal model is proposed to explain the igniter operation.

The single-car accident contributes nearly 42% of the highway traffic accident fatalities, or an average currently of nearly 16,000 deaths. A review of fatal accident statistics from 1900 through 1962 shows that the number of fatal accidents increased rapidly between 1920 and 1930 by more than 2000 per year, that a sharp break occurred around 1930, and that the average increase since then has been less than 500 per year. A comparable long-range review of passenger car improvements shows significant reduction in height, development of enclosed bodies with safety glass, vastly improved brakes and lighting systems and many others. Development in steering and control has concentrated on making it possible to keep out of accidents, and recently, a great deal has been achieved in “packaging the passenger.”

The effect of crankcase emissions and crankcase emission control devices from an air pollution standpoint is discussed in this paper. Blowby flow rates for different engine sizes are presented. The various types of devices which have been approved by the Calif. Motor Vehicle Pollution Control Board are described and their strength and weaknesses are discussed. Finally, some of the design and operating problems of systems currently being used are described.

For the computation of the equilibrium combustion temperature and pressure of hydrocarbon fuel in air, an original set of eighteen equations is enlarged by the energy and mass balance, and the procedure is applied to the cases of constant volume and of constant pressure combustion. Examples of engine combustion, including the effects of air-fuel ratio and the effect of water injection or exhaust gas recirculation, are treated; the results of computation are presented in graphs. The procedure of transformation and coding of the equation system for the solution on an electronic computer is described.

The effect of exhaust gas recirculation on the wear of automobile engine piston rings was investigated by means of the radioactive isotope tracing method. The experiments were performed on a test facility especially designed for lubricating oils, fuels and additives, for their effect on piston ring wear. The piston ring wear rate was recorded during a series of experiments at different engine operating conditions and various amounts of exhaust gas recycling. At the same time, all engine parameters were recorded and the brake specific fuel consumption determined. The exhaust gas was analyzed for the nitrogen oxides content. When 12% of exhaust gas was recycled into the inlet manifold the following results were obtained: 1. A 90% reduction of ring wear at a steady state operation. 2. A 50% reduction of ring wear when the engine was operated on a simulated traffic pattern. 3. A 60–80% reduction in nitrogen oxides in the exhaust gas. 4.

Automobile manufacturers are facing the problem of crankcase emission control in the 1963 model year. Testing has indicated that blowby gases consisting of high comcentrations of hydrocarbons are one of the primary causes of smog and air pollution. A description of three systems under consideration — positive crankcase ventilation, tube type - valveless, and dual action ventilation — is presented in this paper. The basic function is to recycle the blowby gases back into the conbustion chamber for burning, either through the intake manifold, the air cleaner, or both. Test results indicate recycling of blowby gases is advantageous in that it results in cleaner engines as well as eliminating to a large degree hydrocarbon emission.

A research and development program by Studebaker-Packard on catalytic converter system designs is discussed, along with details of specific problem areas encountered, methods used in their solution, and an outline of remaining unresolved problems. Data are presented which show the effect on conversion efficiency of catalyst bed configuration, catalyst temperature, auxiliary air, and gasoline additives. Catalyst warmup rate and more effective utilization of available exhaust heat is discussed. Performance of several catalysts under various automobile operating conditions are illustrated.

For the past seven years, the Ford Motor Company has been working on the development of catalytic exhaust treating systems designed to minimize the emission of certain vehicle exhaust gas constituents. In 1959, the development of a low-temperature, catalytic-converter system for the oxidation of exhaust gas hydrocarbons was described in a paper presented to the SAE. That system, which used vanadium pentoxide as the catalyst, has since been extensively developed in a program that included 250,000 miles of converter evaluation on vehicles. Many of the basic system requirements and problems covered in those tests are relevant in vehicle applications of a catalytic converter system with any type of catalyst. With the insertion of a carbon monoxide limit in the California Exhaust Standard, work on the low-temperature, catalytic converter system was discontinued since this system did not, and was not designed to, oxidize carbon monoxide.

The development of a catalytic converter system for oxidizing exhaust hydrocarbons is presented. Also presented are possible solutions to several mechanical problems associated with catalytic converters such as introduction of secondary air, excessive exhaust system back pressure, attrition loss of catalyst material, and exhaust system noise. Data are presented on the efficiency of vanadium pentoxide catalyst in the Ford catalytic converter system. Overall operating efficiencies of 6-3% can be expected in the removal of exhaust hydrocarbons. During tests with the converter in a smog chamber, average hydrocarbon conversion efficiencies of 88 and 91% respectively were achieved for idle and deceleration, and efficiencies of 68 and 74% respectively were achieved for acceleration and cruise.

To learn about ways of controlling spark plug fouling, research was done in three areas: (1) chemical and physical properties of spark plug deposits, (b) development of an instrument to measure a basic physical property, viz. insulator leakage resistance, as a criterion of spark plug fouling, and (c) engine tests simulating car road performance and aiding the other studies. Ease of deposit fusibility was found to correlate with low resistance and a high degree of fouling. Electron microscopic examination showed that fusibility varied with the area of the ceramic insulator on which the deposit was laid and with the grain structure in a given area. Lead halides are most undesirable in this respect. Spark plugs whose leakage resistances were less than one megohm at normal engine operating temperatures were generally fouled. The corresponding resistances of new plugs were usually around 1000 megohms.

The opinions expressed herein are those of the author and do not necessarily represent those of the Department of the Navy

RESULTS of a research program designed to find improved materials for jet engine blades is presented here. These blades are subjected to a very severe combination of conditions, including high temperatures and stresses. The search for materials capable of meeting these conditions has led from high-temperature alloys to ceramics, and from ceramics to ceramals-combinations of ceramics and metals that, it is hoped, can be made to combine the advantages of both materials. Although the goal of a material that can stand a temperature of 3500 F under the conditions of operation has not yet been reached, substantial improvements have been made in prolonging life at current temperatures and for increasing peak cycle temperatures.