General remarks Although internal combustion engines began to be used in industry long ago - explosive engines about 70 years ago, slow combustion engines about 50 years ago - but their theoretical study lagged behind, as it often happens when introducing new ways of technical progress.The main problem of theoretical research in the field of heat engines in general is to determine the maximum values of thermal efficiency of engines at work without heat losses caused by side causes, not by the principle of conversion itself.

Effective operation of an air lift must be ensured by the correct choice of its main elements; at present, however, such a choice based on calculation presents significant difficulties and is often made at random, without a guarantee of reliability. The reason for this lies in the imperfection of the existing theory of airlift operation. Or rather, a unified theory of this device, so simple in design, still does not exist: we can only talk about various theoretical studies based on different principles. All these studies, to a greater or lesser extent, suffer from unfoundedness, vagueness and even fallacy of their main provisions and assumptions, as well as experimental unverification. The objective of this work is to identify unacceptable provisions of these theories, and to re-construct the airlift theory on the principle of elastic emulsion expansion, eliminating errors inherent in previous works. At the present stage, however, it may already be possible to apply operational curves to airlift calculations, as we did in this work (see article).