Modern requirements have already forced the rotative speed of high-duty gas and oil engines to a point where the difficulty of heat-flow control, especially with cast iron cylinders, tends to arrest further progress in this direction.
In view of this inherent limitation the art of high-speed engine design can best be advanced, not by continued experimental exploration, but rather by first establishing the basic principles underlying heat-flow effects.
The purpose of the present paper is to demonstrate that every internal-combustion engine of given size and type has a safe speed limit and that this can be predetermined upon a rational heat-flow basis. This paper provides an explicit method of procedure, by means of which the design characteristics of a normal gas or oil engine can be critically analyzed for heat-flow effects.
In addition, the matter of relative heat-flow in two versus four-stroke cycle engines, which has been the subject of much controversy, is investigated and certain conclusions are drawn as to the merits of each type.