A small spacecraft microengine with SHF impact on working medium: cooling and dilatometric evaporator valve

The results of experiments and a theoretical research of a cooling method for SHF-transistor crystal of a correcting small spacecraft (SS) microengine are presented. A distinctive feature of a proposed approach is an efficient use of the heat removed from SHF-transistor in the dilatometric evaporator-valve. Generally, this paper continues to create methodological foundations for a design of a correcting SS microthrust engine with SHF-heating of a working medium. This paper is about cooling of SHF-transistor in vacuum with the application of removed energy in a dilatometric valve and for preliminary heating of a working medium before its input to the SHF-chamber. A mathematical model of SHF transistor crystal cooling by the working medium was verified as a result of studies. In case of certain geometrical and initial thermodynamic conditions are met, the intensity of cooling increases and heating of working medium also increases (micro consumption of air cools the experimental surface by 1 W). The heating of working gas, according to theoretical processing, is suffice to create a jet thrust of 1,2 mN. The application field of studied physical processes is the engine-building for small spacecrafts, for example CubeSat 3U, in particular, building of a microengine with SHF-acceleration of a working medium and a dilatometric throttle valve. (paper)