Фізичне обгрунтування методу дифузного поверхневого розсіювання

Abstract

Теоретично обгрунтовано фізичні основи запропонованого автором експериментально-розрахункового оптичного методу визначення деформацій поверхні. Метод базується на ефекті перерозподілу інтенсивностей дзеркальної та дифузної складових розсіяного світлового потоку при локальній зміні кривизни дифузно-розсіюючої поверхні. Вимірюючи ці зміни, можна визначати напружено-деформований стан (НДС) об’єктів.

Physical bases of the proposed by the author experimental-calculation optical method of determination the surface deformation are theoretically interpreted in the article. Available optical methods of the experimental mechanics can be conventionally divided into two groups: interference and optical-geometrical. The first comprises such well-known methods as polarization-optical (photoelasticity), holographic interference, optical sensitive coverings, interference pictures being decoded, resulted under the units loading and deformation. The second group method deal with some geometric measurements (beam deflection in the gradient photoelasticity and mirror-optical method curves radii in the caustic method), which are carried out under loading. The proposed method belongs neither to the first nor to the second group and is based on the creation of the diffuse optical fields and measurement of their parameters changes (intensity) under the unit loading. It is shown that under the unit deformation, which causes the decrease of its surface curvature, the intensity value of the diffuse component, reflected from the diffuse-scattering surface of the light beam, increases, and that of the mirror component, decreases. When the unit is subject to the deformation, caused by the decrease of its surface curvature, the intensity value of the diffuse component of the reflected from the diffuse-scattering surface of the light beam decreases, and that of the mirror component-increases. The effect in question occurs and can be used for the zero-initial curvature (flat), and convex (positive) and concave (negative). It can be used for the measurement of the surface deformation using optical meters. If the convex plate with the diffuse-reflected surface, the axis of which coincided with the direction of the measuring deformation, is fixed on the unit surface, the curvature of the plate will change under deformation and the effect in question can be identified. Thus, the proposed method can be used for the measurement of the local changes of the surface curvature and creation of the optical deformation meters