Three-dimensional parameter extraction method of internal defect of gas turbine blade based on digital ray

Abstract

The invention discloses a three-dimensional parameter extraction method of an internal defect of a gas turbine blade based on a digital ray. The method comprises the steps of arranging two-dimensional detection images of the defect according to pixels for primary finite element division, then performing discrete quantification on thickness of each pixel according to gray-scale values, determining a corresponding relation between grey-scale and the thickness, accumulating finite elements of all the pixels, and extracting a three-dimensional parameter of a defect area.The method is based on a finite element concept; the two-dimensional detection images of the defect are arranged according to the pixel for the primary finite element division; the discrete quantification is performed on the thickness of each pixel according to the gray-scale value; and further, the corresponding relation between the grey-scale and the thickness is determined.The three-dimensional parameter of the defect is extracted by accumulating finite element areas of all the pixels; the deficiency of the traditional radiographic detection method in three-dimensional parameter extraction of the defect can be effectively made up for; and the extraction of the three-dimensional parameter of the internal defect of the gas turbine blade can be achieved more efficiently at lower cost.

Description

【Technical field】 [0001] The invention belongs to the field of industrial ray nondestructive testing, and relates to a method for extracting three-dimensional parameters of internal defects of gas turbine blades based on digital ray. 【Background technique】 [0002] Gas turbine is a kind of rotating impeller power machinery widely used in electric power, navigation and other fields. At present, my country has not yet fully mastered the key technologies of gas turbine core parts manufacturing, and related products mainly rely on foreign imports. The blade is the core aerodynamic part of the gas turbine that interacts with the high-temperature, high-pressure, and high-velocity working medium and realizes energy conversion. It is usually manufactured using a precision casting molding process, and it needs to withstand a huge working load under extremely high temperature and pressure. Because the blades may form defects such as shrinkage cavities, shrinkage porosity, cracks, inc...

AI Technical Summary

Problems solved by technology

However, there are two limitations: on the one hand, due to the high attenuation coefficient of the nickel-based superalloy, which is the material of the blade, the CT with low power cannot completely penetrate the blade effectively.

Therefore, it is precisely because of the high detection cost and extremely low detection efficiency of industrial CT that it is difficult to be widely used in the detection of gas turbine blades in actual engineering.

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