The Design-processing-detection Study Of Micro-structure Surface With Drag Reduction Function

The micro-structured surfaces have the complex effects on the interface mechanics,such as the friction drag reduction. In the past, to the understanding and design of themicro-structure are mostly based on bionics, Due to micro-structured surfaces have thecharacteristics of micro-scale, complex geometric, closely relationship between thegeometric features and function, high three-dimensional topography accuracyrequirement, etc. So on the design, processing and detection of micro-structured surfacehas higher requirements. This paper carries out the research of the integration methoddesign-process-detection on micro-structured surface with the function of dragreduction. The contents are as following.At first, establish the hydrodynamic drag reduction analysis model onmicro-structured surface based on the computational fluid dynamics (CFD) andReynolds averaged N-S equations and Realizable k-? turbulence mode. Analyze severalgrooves with different configurations on the drag reduction effect compared withsmooth surface. And then analyzed the influencing laws of gas drag reduction effect onthe angle, size and space of V grooves, and according to the regularity, design theparameters of V groove.This paper adopts micro-milling for the V-groove which designed in the previouschapter on2A12aluminum alloy plate, then do the orthogonal experimental study offour levels and three factors on micro-milling process parameters which are spindlespeed, feed rate and milling depth. Explore the surface quality, as well as glitches,chipping and other processing defects of V grooves surface in different combinations ofprocess parameters. Analysis the primary and secondary factors affecting surfaceroughness and chipping width of V groove slope by range analysis methods. Then basedon the influence law conclude the micro-milling process parameter combination forV-grooves through optimal selection.For the detection of microstructure surface is difficult, the existing detectionmethods can't meet the quickly and accurately detection requirements of geometricfeatures and surface defects. This paper proposes a detection method based on graymatching for micro-structured surfaces. According to the characteristics ofmicro-structured arrays, this paper select the Normalized Cross Correlation graymatching method as a basis, improve the search strategy. By setting the matchingthreshold, dividing gray match the sensitive area, and adopting progressive step tosearch, detect the location and the gray matching rate of each micro-structure. And thenusing the algorithm with the improved search strategy, detect the size, space and surface defect of micro-structure. Finally, by online detection assay prove the feasibility of thisdetection method.