VERFAHREN ZUM SICHTBARMACHEN VON GRENZFLAECHENSTROEMUNGEN

摘要

Boundary-layer flow conditions of gases are made visible by applying to the surface of a moving or stationary structural body to be exposed to the flow a reactive layer of at least one chemical color indicator, such as an acid-base indicator and/or a Redox indicator or a liquid-crystal indicator, such as a cholesterinic liquid. Then the body is exposed to a flow of gas, such as air, which gas may contain a reagent. The chemical color indicator can also be applied together with gelling means and a moisture binder. The chemical color indicator can also be absorbed by a high-contrast, absorbent paper which is then applied to the body. A metal or plastic foil coated with a binder and/or indicator can also be used for this purpose. A boundary-layer flow pattern image is produced, which can subsequently be recorded by known means.