Method for detecting hydrophobic nature of composite insulator based on dynamic contact angles

Abstract

The invention relates to a method for detecting hydrophobic nature of a composite insulator based on dynamic contact angles. The method is characterized by comprising steps of photographing a contact angle meter at the position perpendicular to a plane where an umbrella skirt or a protecting bush is located through a digital camera or a camera lens, an industrial camera and an image acquisition card to obtain a water drop image, continuously shooting through injection of deionized water to obtain a series of water drop images, calculating out an advance angle theta A through a survey meter, then continuously shooting through extraction of water drops to obtain a series of water drop images, and calculating out an advance angle theta R through the survey meter. The method for detecting the hydrophobic nature of the composite insulator based on the dynamic contact angles has the advantages of (1) high calculating accuracy which represents that influences of roughness of the surface of a material and solute settling on the surface can be restrained to some extent, and an receding angle can better reflect the hydrophobic nature of the surface of the material particularly; and (2) high calculating stability which represents that fluctuations among a plurality of measurement results are small, and calculating stability is high due to the fact that the influence of hysteresis phenomena on measurement of the contact angles are restrained.

Description

technical field [0001] The invention belongs to the field of material performance testing, in particular to a method for testing the hydrophobicity of a composite insulator based on a dynamic contact angle. Background technique [0002] The insulating material of the composite insulator, that is, the shed or the sheath is composed of silicone rubber with hydrophobic and hydrophobic migration characteristics, so the insulation resistance of the surface is still high under the condition of pollution and wetness, and the corresponding pollution flashover voltage of the composite insulator is relatively high. , it can help the power system to suppress the occurrence of pollution flashover. Surface hydrophobicity is a key characteristic of composite insulators, and the hydrophobicity of sheds or sheaths of composite insulators has an important impact on their ability to withstand pollution flashover. [0003] At present, the static contact angle method is mostly used to characte...

AI Technical Summary

Problems solved by technology

In the immersion experiment of the silicone rubber sample, it is found that when the surface of the material is poor in hydrophobicity, the material is easily infiltrated by the solution in a large area when the material is immersed in the solution, but at this time the static contact angle of some points on the surface can reach about 90° or even above In a humid environment, the surface of the silicone rubber is easy to form a continuous water film, and the surface resistance is low, which leads to a serious decrease in the pollution flashover voltage. However, this characteristic cannot be well reflected only by the static contact angle. Validity of hydrophobicity characterization awaits further study

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