To establish the mathematical model of the system of high speed switch valve control the cartridge valve based on analyzing the working principle of the system,and then to analyze the impact of selecting different input signal of high speed solenoid valve and different duty cycle of PWM pulse width modulated signal through simulation software AMSEsim. The results obtained in the high-frequency performance is not very satisfactory, but in the low signal and moderate duty cycle, high-speed switch valve can be good linear control of the cartridge valve.

The nanoboron carbide particle size is 60nm, dispersed in RO reverse osmosis membrane treatment water form water-based nanofluid by adding the dispersant. In experiment, Water-based nanoboron carbide fluid has good resistance sedimentation stability when adding sodium carboxymethyl cellulose as a dispersing agent. Prepared three kinds of water-based nanoboron carbide fluid, the mass fraction of nanoparticles is 0.6%, 0.8%, 1.0%. By establishing a model of U-shaped tube, simulated the water-based nanofluids flow field in U-shaped tube using FLUENT, get velocity flow lines picture and pressure variation graph by CFD post-processing. From simulation results obtained: Water-based nanoboron carbide has good transmission fluid performance when nanoparticles mass fraction of 0.8%.

The water-based nanoTiN fluids were prepared by nanoTiN particles, dispersion medium and dispersant using a two-step method. The dispersion and rheology of nanoparticles in water-based fluid were studied under different preparation conditions. The dispersion and rheology of prepared nanoTiN fluids were evaluated and analyzed from the mass fraction of nanoparticles, mass fraction of dispersant and type of dispersion medium respectively by using the analysis of sedimentation stability and rheological properties. The results show that the above-mentioned factors all have different degree of influence on nanofluids’ dispersion and rheology. The viscosity of nanofluids increases with mass fraction of nanoparticles. A balance amount of mass fraction of dispersant will improve nanofluids’ dispersity and fluidity. The dispersion effect of deionized water is the best when the nanoparticles dispersed in different dispersion medium.

That the key components of Water-based hydraulic components are easy to wear down in the course causes sealing performance degradation and then arises leakage, which affects water-based component life and hydraulic system operational reliability. Considering the characteristics of ceramic materials, the ceramic method is applied to improve the key parts of water-based component, and then wear and failure mechanism analysis was done on ceramic water-based component.

This paper presents the parameters and assumptions of the hydrostatic guide rail in both ideal and actual working conditions, the simulate calculation of fluid-solid heat coupling field between gas film and the bearing surface is finished by Fluent based on finite volume method. By analyze and compare the results after post-treatment, we gain the effects caused by guide way’s structure and deformation on the formation of film pressure field, temperature field inside gas film, besides this paper also provides relate conclusions.