
VISUALIZATION OF THE gas-dynamic STRUCTURE OF PLASMA FLOWS OF A PNK-50 plasma torchusing THE SHADOW METHOD
Author(s) -
I. P. Gulyaev,
В. С. Кузьмин,
Maxim Golubev,
Pavel Tyryshkin,
A. Dolmatov
Publication year - 2018
Publication title -
vestnik ûgorskogo gosudarstvennogo universiteta
Language(s) - English
Resource type - Journals
eISSN - 2078-9114
pISSN - 1816-9228
DOI - 10.17816/byusu20180461-68
Subject(s) - plasma torch , torch , laminar flow , plasma , nozzle , turbulence , schlieren , mechanics , supersonic speed , reynolds number , materials science , chemistry , physics , thermodynamics , welding , quantum mechanics , metallurgy
The paper presents the study of the gas-dynamic structure of air plasma flows produced by the PNK-50 spray torch using the shadow (schlieren) method. The operation of the plasma torch was studied in three different configurations, differing, among other things, by the diameter of the output section of the channel: 6, 8, 10 mm. The subsonic and supersonic modes of operation of the plasma torch were investigated in the range of plasma-forming air flow 1.4-10.5 g / s and arc current range 140-230 A.In all typical modes of operation of the plasma torch, the flow has a developed turbulent structure with a full angle of jet opening between 23 and 27 degrees. An additional mode of operation of the plasma torch with an output nozzle diameter of 14 mm allowed the realization of a laminar flow regime. It is established that the laminar-turbulent transition is observed in the range of Reynolds numbers 400 - 900. The pattern of supersonic flow impinging a flat barrier - a substrate for placedat a distance of 85 mm from the plasma torch, is visualized.