_applied_  
_sciences_  
_Article_  
Drag Reduction Analysis of the Hydrostatic Bearing with  
Surface Micro Textures  
[PERSON] 1,  
trapezoid has a higher load-carrying capacity than the zigzag texture, and the maximum pressure value is reduced by 36% compared to the smooth journal. In terms of pit-like textures, [PERSON] et al. [3] analyzed the effects of spherical, cylindrical and parallelepiped textures on the minimum oil film thickness, maximum pressure, axial flow velocity and friction force on the shaft diameter surface under the condition of stable flow field by using the finite element method, and the cylindrical texture performance improved more. [PERSON] [4] found through experiments that with a reasonable design of geometric shapes and distributions, micropits can obtain nearly 2.5 times the carrying capacity of smooth surfaces. [PERSON]'s [2] research shows that texture height has a greater impact on tribological properties than texture area ratio. Through experimental comparison, [PERSON] [5] found that reducing the texture height and inclination would reduce the LCC. [PERSON] [6] applied numerical methods to study the effect of microgrooves on the axial direction of the bearing pad wall on the lubricity of radial hydrostatic bearings when cavitation effects were considered. It shows that the microgrooves can increase the minimum oil film thickness and reduce the frictional resistance under the condition of small depth and low load (eccentricity \(\varepsilon<0.15\)); under the condition of large depth and high load (\(\varepsilon>0.15\)), the microgrooves can reduce the friction force, but simultaneously, the thickness of the oil film is reduced. In terms of thrust hydrostatic bearing research, [PERSON] [4] used the load capacity/friction coefficient transition point to measure the performance of the bearing, and studied the effects of the ratio of the area of the crater, the depth of the crater and the diameter of the crater in the transition point of the LCC and obtained the best result. [PERSON] [7] optimized the geometrical parameters of the fan-shaped straight groove texture on the bearing surface and considered that the microtexture had different optimal parameters under different constraints and objectives. He analyzed the effect of groove texture on the fluid thrust lubrication mechanism of thrust washers and found that the width and number of grooves have optimal values for load carrying capacity. Regarding the location of texture distribution, [PERSON] [6] simulation found that the microtexture model arranged in the maximum pressure region can reduce friction and oil film thickness compared with the smooth wall model. [PERSON]'s numerical study found that there is a reasonable density and distribution for the oil film LCC. [PERSON] [8,9] found in the micropit texture research that the global texture model cannot effectively improve the LCC, but it is suitable for mechanical seals. [PERSON] [1] proposed the \"lubrication effect of microbumps\", which believes that the microbumps on the surface hinder the movement of the fluid. When the fluid flows through the microbumps, the pressure rises rapidly and cavitation causes the pressure asymmetry, resulting in additional LCC. [PERSON]'s [10,11] numerical analysis of textured slider bearings found a \"reflow phenomenon\". When the texture depth increases to a certain value, backflow will occur, and the backflow will reduce the pressure gradient and LCC. [PERSON] [12] found that the pit-textured surface lubricating fluid penetrates into the surrounding area to reduce friction and wear. [PERSON] experimentally verified this phenomenon and summarized it as \"secondary lubrication effect\". [PERSON] [4] discovered the phenomenon of \"inlet suction\" when studying low-convergence textured wall bearings: unlike the classical shear force that entrains the lubricating oil to form hydrodynamic pressure, the phenomenon is that the textured area at the bearing inlet produces a lower pressure than the outside air.