The existing sources of the operating fluid used in aviation and rocket-space technology are analyzed. The disadvantages of inert gas cylinders used as a source of the operating fluid of the component supply system in jet engines are considered. An alternative to the gas pressure system is a low temperature solid propellant gas generator (LTGG) with a coolant. Controllable powdery components supply scheme of an air-breathing engine (ramjet) is proposed. The principle of operation of such a feeding scheme is described. To ensure the stability of the output characteristics of the LTGG, a valve system is used. The requirements for the gas source and combustion products (CP) involved in the operating process have been determined. The analysis of the existing methods of cooling the CP is carried out. It was revealed that the low-temperature solid-propellant gas generator with a powdery capacitance coolant meets the most fully the above requirements, the principle of operation, which is based on the heat transfer wave localization effect. Solid propellant with the following composition: 38 % AP + 38 % Octogen + 24 % SKI-NL is selected. The CP temperature, at a pressure in the combustion chamber of 6 MPa, is 1545 K, and the CP gas constant is 459.4 J / kg·K, the condensed phase is absent, and the water vapor content in the operating fluid does not exceed 1.6 %. The combustion of the proposed propellant produces a significant amount of combustible components – 60 % CO, 4 % H2, > 1 % CH4. The use of valves on cold gas ensures the reliability of the controlled supply system of powder components, and, accordingly, the entire engine. Based on the results of the work, conclusions were made about the correspondence of the obtained parameters of solid propellant and LTGG to all the requirements set.
Mathematical Simulation of Convective Heat Transfer in the Low-Temperature Storage of Liquefied Natural Gas
