Rykunich I. Efficiency prediction of the small electromagnetic valves in aerospace systems

The dissertation is devoted to the development of scientific base and practical recommendations on the determination of serviceability reserve of the compact-sized pneumatic electromagnetic valves (EMV) at the design stage. The classification of small-size EMV which are used in aerospace equipment systems is provided. The algorithm for determining serviceability reserve of the electromagnetic valves is presented. It includes solutions for the two interconnected tasks: determination of the parametric operating limits and determination of the fatigue strength range of the critical elements in the electromagnetic valves, which limit their normal operation. The analytic formulas for defining the serviceability reserve of the EMV at the design stage were obtained. The character and intensity of technical condition and main structural and functional parame-ters change of the EMV during operation were experimentally determined. The peculiarities of the fatigue process development in the material of electromagnetic valves rod elements with the two positioned polar-ized electromagnetic drive were defined. For the several constructional materials the empirical dependences were obtained for the number of EMV operational cycles before the destruction of rod elements, depending on the kinetic energy of the valve moving parts. As a result of the conducted experimental and theoretical work the scientific theory of the efficiency of the compact-sized EMV for aerospace systems was further developed. The findings are based on the stochastic models of technical condition change of EMV units and elements, and their functional parameters under operational load. Implementation of these models at the design stage of the new electromagnetic valves for modern aerospace systems allows meeting the requirements of reliability and failure-free performance during the period of normal operation. Based on the results of conducted research enterprise standard STU-273:2012 "Method of the ser-viceability calculation for the electromagnetic valves at the design stage" was created. Main findings of the conducted research were implemented in the design process of the EMV at Public Joint Stock Company "Kyiv Central Design Bureau of Valves".