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The theory of submerged jets is applied quantitatively and qualitatively to diesel fuel sprays, based on simple considerations of the inherent invalidity of the single-particle “ballistic” approach. Approximate theoretical results are obtained for penetration velocity, penetration versus time, and fuel-air ratio within the spray. Modeling experiments are discussed and the jet approach used to explain two types of diesel combustion situations-fuel entrapment by insufficient penetration in the presence of air swirl and the efficacy of the MAN process.

A unique system has been devised to measure and telemeter critical temperatures of reciprocating engine components. A prototype has been used to measure the piston pin bearing temperature in a full-scale EMD 2-567D diesel engine.

REDSOD, an acronym for Repetitive Explosive Device for Soil Displacement, utilizes the energy generated within a combustion chamber by the combustion of compressed air and a hydrocarbon fuel to displace and move soil or material. An integral wedge-shaped base shoe with a large exhaust opening in its top surface is pushed into a soil overburden at depths up to 5 ft or more by a transporting vehicle. When the combustion chamber pressure has reached a maximum value, the hot, high pressure gases are released through the exhaust opening under the soil overburden. The soil is disaggregated and displaced up and out of the excavation. Deflectors can turn the direction of the soil's trajectory to deliver it to one side of the excavation. A greatly increased productivity per unit of equipment is possible over conventional earthmoving means.

Exhaust heat utilization for internal combustion engines has centered around turbosupercharging in recent years, neglecting the promising field of compounding a piston engine with a gas turbine in which, unlike turbocharging, turbine power is fed back to the engine crankshaft. The piston engine can cope with high gas pressure and temperature, whereas the gas turbine can efficiently utilize the energy at relatively low pressure and temperature and large volume flows. By compounding, this-piston engine will handle the high pressure, high temperature phase of the combustion cycle and extend the expansion ratio of the gases to atmospheric pressure by completing the low pressure, low temperature phase in the gas turbine. The marriage of the two engines will result in an outstanding power package with the highest thermal efficiency possible.

This paper presents the results of an investigation of the normal sources of hydrocarbon emissions of passenger cars. The sources were considered to consist of the crankcase ventilation and exhaust systems, the carburetor, and the fuel tank vent. Many studies involving the emissions from several of these sources have been conducted and reported; however, it is believed that this is the first study designed to develop emission data from all the sources of a single group of passenger cars. Although only five vehicles were used, several mechanical conditions and engine and power train configurations were examined. The largest single source of hydrocarbon emissions was found to be the exhaust, followed by the road draft tube. Relatively minor emissions were measured as a result of fuel evaporation from the carburetor and fuel tank during periods of operation and hot soak.

This paper discusses the experimental work that produced a revised military standard piston ring (conformable steel-rail oil control ring) with improved oil consumption and wear characteristics. The testing of these parameters was accelerated by the use of radio-tracer techniques. The effects of variables such as engine speed, load, jacket temperature, air-fuel ratio, intermittent starts and stops, and cyclic load operation is described. Performance characteristics of the present standard and experimental piston rings are included.