WORKING PROCESSES OF INTERNAL-COMBUSTION ENGINES 190058

A new type of automotive engine should be the quest of all designing engineers. Investigation has revealed the fact that 68 per cent of all tractor engine troubles occur in magnetos, spark-plugs and carbureters, the accessories of the present-day automotive engine. Four-fifths of the fuel energy supplied is regularly wasted, yet the fuel is a liquid meeting severe requirements of volatility, etc., and is already becoming scarce and costly. In an airplane, fuel is carried by engine power. In ocean-going cargo vessels it increases available revenue space. It is at once clear that for purely practical reasons the question of fuel economy, no less than the question of the nature of the fuel, becomes momentous. What fuel will do is entirely a question of what process it is put through in the engine; in what way combustion is turned into power.

In the paper the physical processes underlying the conversion of combustion energy into power are discussed, together with the various methods for producing the pressure differences needed for the operation of ordinary heat engines. The author states both the theoretical and the practically attainable energy utilizations of engines and turbines of the compressor, explosion and evaporation types. Improvements are found to be obtainable in all three types and some suggestive lines of work are pointed out. Among these the compressor engine and the steam powerplant offer interesting possibilities in competition with the work already done by the Brayton, Kraus and Armengand-Lemale engines. In connection with the investigation of electrical combustion batteries, the author asks whether it would be possible to use the combustion process with our ordinary fuels to deliver electric current in a primary battery, and what the fuel utilization of such a battery would be. It is known that from 1910 to 1912 Baur, Taitelbaum and Ehrenberg, in Germany, succeeded in combining such fuel batteries and obtaining electromotive forces close to those theoretically possible.