Device for measuring forward contact angle and backward contact angle

Abstract

The invention provides a device for measuring a forward contact angle and a backward contact angle. The device comprises a base, a hoisting rack, a motor, a shaft coupler, a rotary lower shaft, a torsion rod, a rotary upper shaft, a rotary flat plate, a movable rack, a camera and a cold light source lamp. The device provided by the invention has the beneficial effects that 1, a positive and negative assisting power system composed of the motor, the rotary lower shaft, the torsion rod, the rotary upper shaft and two same rotary angle measurement sensors can provide positive and negative assisting power, the measurement precision is improved and the measurement repeatability is ensured; 2, the measurement operation is simple, the precision is high and the problem that liquid drops in an inclined plate are difficult to move under the action of gravity is solved; 3, a camera and cold light source automatic following system composed of the rotary angle measurement sensors, the movable rack,the camera, the cold light source lamp and the like can be used for photographing shape changes of the liquid drops along the rotation of the rotary liquid drops, a critical point angle is found anda rotary speed of the critical point is recorded.

Description

technical field [0001] The invention relates to a device capable of measuring contact angles, in particular to a device for measuring advancing contact angles and receding contact angles. Background technique [0002] The contact angle refers to the tangent of the gas-liquid interface at the intersection of gas, liquid and solid. The angle θ between the tangent on the liquid side and the solid-liquid boundary is a measure of the degree of wetting. [0003] The contact angle in Young's equation is the contact angle under the assumption that the solid surface is flat and smooth, chemically uniform and isotropic, and the three phases of solid-liquid-gas reach a state of thermodynamic equilibrium. It is also called the static contact angle, that is, solid-liquid-gas The contact angle at which the gas three-phase contact line is stationary and does not move. [0004] However, the actual solid surface may have roughness, uneven chemical composition, contamination, etc. to a certa...

AI Technical Summary

Problems solved by technology

This patent measures the contact angle of the droplet during its movement, and does not measure the advancing and receding contact angles when the droplet has a tendency to move but has not yet moved.

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