Analysis And Calculation Of Turbine Blade Temperature Field

Turbine blade as one of the most important durability components in gas turbine, which work in high rotation speed and high temperature, so burning phenomenon is easy occurrence in the highest parts of turbine blade. The burning of blade is one of the most important reasons which cause gas turbine failure. Therefore, it is necessary to test the temperature of turbine blade. This paper collected infrared image of turbine blade using infrared thermometry, and applied of digital image processing methods to analyze temperature field of turbine blade.Based on infrared image analysis temperature distribution of turbine blade, the first thing to do is image segmentation. This paper studied the threshold segmentation algorithm and regional segmentation algorithm, and did MATLAB simulation on the common segmentation algorithm. We analyzed the simulation results and found that Otsu method can be better used in the images which have large difference between object and background. Therefore, Otsu method can separate turbine blades from the surrounding environment.Isotherm chart of temperature field is one of the important parameter in turbine blade temperature analysis. However, if we want to draw isotherm chart based on infrared image of blade, image edge detection technique as one of the most important digital image processing techniques need to be applied.In this paper, we studied the classical differential edge detection operator, Canny edge detection operator, based on mathematical morphology edge detection and boundary tracing algorithm. After MATLAB simulation is done on these algorithms we found that the edge extracted based on boundary tracing algorithm is closed and 1 pixel width. Therefore, the boundary tracing algorithm is suitable for description of turbine blade isothermThe blade image collected by infrared thermometry is gray image which only have 256 grayscale.The human eye is not sensitive to the gray image making it difficult to directly observe the temperature distribution. This paper did false color enhancement for gray image. This paper studied false color coding based on RGB color space and false color coding based on IHS color space. A variety of transformation functions for gray image processing is used. Through false color image we can intuitive observe temperature field of turbine blade. This paper used image segmentation, image edge detection and gray image false color enhance technology. Through the isotherms of blade, false color image of blade and other' three-dimensional surface chart show the temperature distribution in the blade surface.