PHYSICS AND THE INTERNAL COMBUSTION ENGINE 5

In the internal combustion engine using liquid fuel, a notable invention was that of Akroyd Stuart (1890) in which he employed a charge of air alone, and injected the spray of fuel into it within the cylinder during the compression stroke. In a later patent, he introduced a dividing wall into the combustion chamber with a connecting passage of small area. Both inventions have many derivations to-day. Two years later followed Diesel, the best known name to the general public in the internal combustion engine world.

)6-4 01

J. n.

“I

EFFICIENCY |-(

III...”- III--

iiii=llll III-IIEII III-III.“- III-III..-

IO ‘20 3O 4O 50 60 7O 80 30 [00

Fig. 1. Compression Ratio 77.

Theoretical Thermal Efficiencies for Different Compression Ratios in Three Symmetrical Cycles.

Physical research work on the engine in this country in the days before the War, is often synonymous with the name of Dugald Clerk, who did so much in investigating the heat processes of the

engine himself, and in co-ordinating and classifying the work of others.