The analysis of texture direction feature of strip surface defects was reasonable or not affected the correctness of defect image recognition. To strip surface defects and texture direction feature abstraction which described defect image, the relationship between detection distance and detective direction angle and the basic methods of texture direction feature abstraction of defect image were given. Based on the case studies of crack defect image to strip surface with both noise and noise free, the texture feature should take the maximum value in texture direction and the minimum value in the direction perpendicular to the texture were proposed. The detection distance should be selected according to the specific situation, not too large or too small and the threshold value should be small when analysis defect image with noise.

To understand the flow field distribution inside the steam distributor, and to compare the distribution effect of the three vertical steam distributor and the three spheres steam distributor, the inside flow field was simulated by Fluent and the effect of density distribution, gas phase distribution and velocity field on steam distribution was analyzed. From the results of numerical simulation, it can be seen that, in the process of steam dryness and flow distribution, three ball steam distributor is better than three vertical distributor. The establishment of a three spherical steam distributor provides a reference for the construction of actual field operations and high temperature and high pressure spherical distributor.