Float type optical fiber Bragg grating density sensor of Pb-Sn (plumbum-stannum) molten alloy

Abstract

The invention relates to a float type optical fiber Bragg grating density sensor of a Pb-Sn (plumbum-stannum) molten alloy, belonging to the technical field of photoelectric measurement. The lower half part of the sensor is arranged inside the Pb-Sn molten alloy; a buoyancy force transmission rod is pulled as a tapered float into which lead is filled is subjected to the action of a buoyancy force and the gravity; the right end of a constant-strength cantilever fixed on a protecting cylinder is subjected to an upward pulling force through a steel bar equal armed lever and a connecting rod, so that the constant-strength cantilever has a deflection deformation, and furthermore the displacement of a central refection wavelength of an optical fiber Bragg grating adhered to the upper and lower surfaces of the cantilever is generated; a temperature measuring grating adhered to the inner wall of a connecting rod sleeve is used for measuring the temperature of the molten alloy; and the density of the molten alloy under the temperature is calculated according to a linear relationship between the buoyancy force to the float and the density of the molten alloy. As the sensor is arranged into the molten alloy for on-line monitoring, the noise interference caused by the on-site environment is reduced, and moreover the constant-strength cantilever is adopted as the wavelength turning mode, the sensor is strong in interference assistance, high in instantaneity and good in linearity.

Description

technical field [0001] The invention relates to a float type optical fiber Bragg grating Pb-Sn molten alloy density sensor for measuring the density of molten alloy, which belongs to the technical field of optoelectronic measurement. Background technique [0002] Density is one of the important physical parameters of various substances, and its measurement is widely used in modern defense, science and technology, industry and other fields. Due to the high temperature and other factors of the molten alloy, it is difficult for the general liquid density meter to be directly applied to its measurement. At present, the methods for studying the density of molten substances include the gamma ray method and the improved static drop method. The γ-ray density meter adopts the principle of γ-ray transmission, which can measure the density of the material in the sealed tank, tank, and pipeline non-contact. It has strict restrictions on the selection of radioactive sources and installa...

AI Technical Summary

Problems solved by technology

The improved static drop method is to form a cylindrical-like shape in the preset cylindrical hole by extruding the molten alloy between the upper and lower crucibles. The shape is imaged by the CCD camera and X-ray emitting device, and then input into the computer. After image processing such as feature extraction, the volume of the part of the alloy is calculated, and then the density of the alloy is calculated. However, this method has strict requirements on the software and hardware environment and measurement methods required for operation and use, and it is difficult to achieve portable real-time measurement.

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