Dynamic operating processes of the turbojet engine air launch unit

Air launch units are widely used in aviation, allowing them to save the life of turbojet engines. The screw compressors used in the installations have the passport characteristics, the data of the factory tests. But when working online, these characteristics change. The purpose of the article is to develop mathematical models of the operation of screw compressors in real-world operating conditions of a turbojet engine air launch unit. The equations of gas state, continuity, motion, and heat transfer equation are used. Air is represented as a compressible perfect gas flowing in a cylindrical sleeve. It has been established that in the operating pressure range (0.25-0.35 MPa), the compressor mass flow rate is a linear increasing function of pressure, and the temperature at the compressor outlet is a linear decreasing function. The pressure change along the sleeve occurs non-linearly. The closer the exit from the sleeve is, the more the velocity graph deviates upward. The thermodynamic temperature drops along the axis of the channel. Using the developed mathematical model, it is possible to more accurately calculate aircraft structures at the design stage.
EDN: MCIERM, https://elibrary/mcierm

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