Axial deep creep-feed grinding machining technology is a high efficiency process method of engineering ceramics materials, which is an original method to process the cylindrical ceramics materials or hole along its axis. The analysis of axial force and edge fracture proved the cutting thickness and feed rate could be more than 5-10 mm and 200 mm/min respectively in once process, and realized high efficiency, low-cost process of engineering ceramics materials. Compared with high speed-deep grinding machining, this method is also a high efficiency machining technology of engineering ceramics materials as well as with low cost. In addition, removal mechanism analyses showed that both median/radial cracks and lateral cracks appeared in the part to be removed, and the processed part is seldom destroyed, only by adjusting the axial force to control the length of transverse cracks.
The near wake structure, the wake-flow characteristics and the drag coefficients behind a modified square stay-cable （MSC） with sinusoidal variations of the cross-section area along the spanwise direction are investigated experimentally and numeri- cally. The Reynolds numbers are chosen as 100 and 500 for the laminar flow and Re = 6 000 and 22 000 for the turbulent flow. The detailed near wake structures, the velocity fields and the force coefficients for the MSC are captured, the effect of the Reynolds number on the flow structure for the MSC is studied. The numerical and experimental investigations show that the free shear layers from the leading edge are widened and prolonged and then roll up into vortices further downstream the MSC, unlike a straight square stay-cable （SSC） under the same flow conditions. As a result, the distinct mean drag reduction and the fluctuating lift suppression are observed for all Reynolds numbers, a drag reduction of at least 15.8% and the rms lift coefficient reduction of up to 95% are observed, as compared with the case of a straight square stay-cable at Re = 500.
