Aerospace Technic and Technology

This study presents the main results of research on the assessment of the change in the influence of the adiabatic index on the total pressure conservation coefficient and the length of the direct compression jump in the supersonic part of the external compression inlet device, considering the processes occurring with an increase in the number M in the range of hypersonic flight speeds. This study investigates the dependence of the total pressure conservation coefficient and the length of the direct compression jump of the hypersonic external compression inlet device. The study aims to develop a flat hypersonic external compression inlet device. This study aims to assess the influence of the adiabatic index of the hypersonic flow on the total pressure conservation coefficient and the length of the direct compression jump of the hypersonic external compression inlet device. The following tasks were solved to achieve the goal: modeling the flow in the supersonic part of the flat hypersonic external compression inlet device; calculation of the total pressure conservation coefficient and the height of the direct compression jump in the supersonic part of the flat hypersonic external compression inlet device; and assessment of the influence of the number of braking surfaces on the total pressure conservation coefficient and the height of the direct compression jump in the range of hypersonic speeds in the supersonic part of the hypersonic input device of the external compression. The influence of the adiabatic index on the total pressure conservation coefficient and the length of the direct compression jump in the supersonic part of the input device of the external compression was studied using the gas-hydraulic theory of oblique compression jumps. The studies were conducted at a design altitude of 0 km, in the range of M numbers from 4 to 10 and with a change in the number of braking surfaces from 3 to 80. To study the influence of the adiabatic index on the total pressure conservation coefficient and the length of the direct compression jump in the supersonic part of the input device of the external compression, modeling was performed with a constant adiabatic index (1.41) and a variable that depends on the number of M at the inlet to the input device, considering the processes occurring with an increase in the number of M in the range of hypersonic flight speeds. The modeling results showed that the adiabatic coefficient has the most significant effect on the total pressure conservation coefficient and the height of the direct compression jump in the supersonic part of the hypersonic external compression inlet device with a number of braking surfaces up to 20. The flow modeling results obtained in the supersonic part of the hypersonic external compression inlet device can be used to justify the number of braking surfaces for the calculated number M. The scientific novelty and practical significance of the research results lie in the fact that new data are obtained on the total pressure conservation coefficient and the height of the direct compression jump in the supersonic part of the hypersonic external compression inlet device with an adiabatic coefficient that depends on the number M.

hypersonic external compression inlet device; number M, angle of inclination of the braking surface, angle of inclination of the compression jump; total pressure conservation coefficient; length of the direct compression jump; intensity of the compression

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