Authors

The influence of slot wall mobility on gas flow in в "piston ring-cylinder mirror" slot of a compressor

DOI: 10.17586/1606-4313-2020-19-2-19-25
UDC 621.512

The influence of slot wall mobility on gas flow in в "piston ring-cylinder mirror" slot of a compressor

Pronin V.A., Tsvetkov V.A., Molodova Yu. I., Zhignovskaya D.V.

For citation: Pronin V.A., Tsvetkov V.A., Moldova J.I., Zhignovskaia D.V. The influence of slot wall mobility on gas flow in в "piston ring-cylinder mirror" slot of a compressor. Vestnik Mezhdunarodnoi akademii kholoda. 2020. No 2. p.19-25

Abstract
The article provides prerequisites for calculating leaks in the sealing units of a piston compressor, taking into account the mobility of the walls of the "piston ring-cylinder mirror" slot. A mathematical model of mass transfer in a piston seal is being developed. To date, a mathematical model of the working process when piston is sealed by rings is known, based on the use of thermodynamics equations of variable mass, as well as a system of differential equations describing the stationary laminar radial flow of a real gas in a narrow dry gap with fixed walls. The calculation of leaks and overflows, carried out without taking into account the mobility of the "piston ring-cylinder" channel, can be adjusted to obtain more accurate results. During the operation of the compressor, the piston performs a reciprocating motion, and there is also a pressure drop in the radial slot. These circumstances must be taken into account, namely the alternating movement of the wall (o-ring) and the pressure nature of the gas movement in the gap under consideration. They will affect the distribution of the gas velocity in the radial gap, as well as the elementary flow rate.

Keywords: piston compressor, leaks, overflows, piston rings, gas flow, mass transfer, gas velocity, gas flow rate, viscosity, pressure drop, mobility, mathematical model.

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