Pencil hardness testing,electrochemical impedance spectroscopy,scanning electron microscopy,and scanning Kelvin probe microscopy were used to study the local corrosion characteristics of a graphene-oxide-modified inne...Pencil hardness testing,electrochemical impedance spectroscopy,scanning electron microscopy,and scanning Kelvin probe microscopy were used to study the local corrosion characteristics of a graphene-oxide-modified inner coating.The effect of chloride concentration on the corrosion of the damaged inner coating was studied.The effects of chloride ions on damaged internal coatings and graphene-oxide-modified internal coatings were investigated.It was proposed to add graphene oxide into the epoxy coating to effectively inhibit the metal corrosion at the breakage.Because of the existence of graphene oxide(GO),the modified coating had a better physical property and had the effective infiltration of H2O and Cl^- into the coating.The results showed that graphene oxide coatings can give X80 steel better corrosion resistance in sodium chloride solution.展开更多
Flow measurement is important in the fluid process and transmission system. For the need of accuracy measure- ment of fluid, stable flow is acquired. However, the elbows and devices as valves and rotary machines may p...Flow measurement is important in the fluid process and transmission system. For the need of accuracy measure- ment of fluid, stable flow is acquired. However, the elbows and devices as valves and rotary machines may pro- duce swirling flow in the natural gas pipeline networks system and many other industry fields. In order to reveal the influence of upstream swirling flow on internal flow fields and the metrological characteristics, numerical si- mulations are carried out on the swirl meter. Using RNG k-e turbulent model and SIMPLE algorithm, the flow field is numerically simulated under swirling flows generated from co-swirl and counter-swirl flow. Simulation results show fluctuation is enhanced or weakened depending on the rotating direction of swirling flow. A coun- ter-swift flow increases the entropy production rate at the inlet and outlet of the swirler, the junction region between throat and divergent section, and then the pressure loss is increased. The vortex precession dominates the static pressure distributions on the solid walls and in the channel, especially at the end region of the throat.展开更多
基金Project(51674212)supported by the National Natural Science Foundation of China。
文摘Pencil hardness testing,electrochemical impedance spectroscopy,scanning electron microscopy,and scanning Kelvin probe microscopy were used to study the local corrosion characteristics of a graphene-oxide-modified inner coating.The effect of chloride concentration on the corrosion of the damaged inner coating was studied.The effects of chloride ions on damaged internal coatings and graphene-oxide-modified internal coatings were investigated.It was proposed to add graphene oxide into the epoxy coating to effectively inhibit the metal corrosion at the breakage.Because of the existence of graphene oxide(GO),the modified coating had a better physical property and had the effective infiltration of H2O and Cl^- into the coating.The results showed that graphene oxide coatings can give X80 steel better corrosion resistance in sodium chloride solution.
基金supported by the National Natural Science Foundation of China(51579225)
文摘Flow measurement is important in the fluid process and transmission system. For the need of accuracy measure- ment of fluid, stable flow is acquired. However, the elbows and devices as valves and rotary machines may pro- duce swirling flow in the natural gas pipeline networks system and many other industry fields. In order to reveal the influence of upstream swirling flow on internal flow fields and the metrological characteristics, numerical si- mulations are carried out on the swirl meter. Using RNG k-e turbulent model and SIMPLE algorithm, the flow field is numerically simulated under swirling flows generated from co-swirl and counter-swirl flow. Simulation results show fluctuation is enhanced or weakened depending on the rotating direction of swirling flow. A coun- ter-swift flow increases the entropy production rate at the inlet and outlet of the swirler, the junction region between throat and divergent section, and then the pressure loss is increased. The vortex precession dominates the static pressure distributions on the solid walls and in the channel, especially at the end region of the throat.
