METHOD FOR VISUALISING A GAS OR LIQUID FLOW ON AN OBJECT SURFACE

摘要

The invention relates to experimental aero- and hydrodynamic engineering, in particular to optical methods for studying a gas or liquid flow structure on object surfaces. Said invention makes it possible to study several flowing modes with a single preparation of the object. The inventive method consists in coating the object studied surface with a viscous fluid layer containing optically foreign particles insoluble therein, in displacing said particles by gravity together with the viscous fluid, in recording two or several sequential pictures of the particle distribution on the studied object surface during the gas or liquid flow mode of interest, in determining the particle motion parameters and in recovering the picture of the gas or liquid flow on the object surface by analysing the thus recorded sequence, wherein, due to the fact that the flow picture recovering requires a small particle displacement, the object can be reused without the additional preparation thereof for studying an another flowing mode. In order to visualise the surface flows on a movable object, the inventive method also consists in additionally providing the surface of said object with an arrangement of markers which are rigidly connected thereto and are optically distinguishable from the particles introduced into the viscous fluid, in recording said marker arrangement simultaneously with the particle distribution picture recording, in determining the motion parameters of the object as a whole by analysing the recorded marker displacement parameters, in compensating the particle motion parameters on the object motion as a whole and in recovering the picture of the gas or liquid flow on the object surface using the thus obtainable compensated particle motion parameters.