Role in the development of liquid hydrogen oxygen in bearing

So related information are relatively limited liquid hydrogen oxygen is a widely adopted international advanced engine fuel or propellant, such as America's SSME oxyhydrogen motivation, liquid rocket engine in our country also USES liquid hydrogen as a fuel or propellant, its degree is low, low temperature representative due to LH1 density is far lower than the LO) Density, oxygen pump bearing speed than hydrogen, hydrogen engine speed in commonly 4000 min, oxygen speed to 2000 m. And bearing load with the improvement of luck I ability request has been increasing, I countries are developing speed of the rolling bearing in the 8000 / min. American space technology is the highest form of space technology, the world for many years, the United States has labelled the high-speed bearing high reliability and long life of the key technologies of reusable launch vehicles for SSME turbine pump bearing a lot of research work. American Walowit etc on the liquid fuel pump for SSME study of dynamic and static pressure bearing, bearing diameter is 96. 52 m, length is 50. 8 m and speed 36000 / min, the lubricating medium for liquid hydrogen as the working medium. Current NASA is committed to SSME fuel pump and other future space carrying on the system of dynamic and static pressure bearing a number of research work. Before the bearing design of axial back to oil tank. In addition, the petrochemical industry in the United States are in carries on the research of dynamic and static pressure bearing, its future research direction are: (1) study design without return chute calculating program for static pressure bearing, for the forecast and to compare the influence of axial back into the groove on the bearing performance is necessary: の is preparing to thrust bearing the accuracy of the models and assumptions for further research. Japan on the static pressure bearing and a lot of research and experimental work. In 1991 Japan 1 h1 use computer devised a bearing axis movement, experimental speed success of 86000 / min. IHI 1995 much oil cavity of dynamic and static pressure bearings used in LE5 liquid hydrogen pump speed reached 500 omin. In 2000, the 1 h the optimization design method has carried on the back to back into the groove of dynamic and static pressure bearing design, and test has been carried out in 60000 r/min. Results show that when the pressure in the lower 0. 18 mpa, the full round of pump rotation stability and no wear and tear, and the rotor is at a relatively low amplitude through the first and second order critical speed. Also now, with the increase of temperature, axial force balance becomes unstable, and at the start and stop instantly have larger vibration, is made in this way, no serious damage during pump operation. France also made the corresponding research work in this respect, SNECMA called Aptech space turbine pump prototype is developed, using liquid lubrication bearing level 60 kn engine LH12 turbine pump in the normal condition of success, bearing the dn value of 500000 ( mm·r / min) 。 SNECMA after use a unique design methods, tools, and optimization of processing technology, the liquid lubricated bearing ( Especially with oil cavity of dynamic and static pressure bearing) Carried out extensive research work, in 2004, they found that in the experimental stage of start and stop, when turn speeds to 2000 / min, he was promoted which reduces the rotor shaft and shaft sleeve of wear and tear. In the actual running state, the experimental duration of more than 7008, the maximum speed of 11000 / min, the corresponding dn value of 500000 mm·r / min) Wear, shaft and shaft sleeve is very low, the friction material is satisfactory. For liquid rocket engine turbopump in China with the study of the high-speed bearing and relatively backward compared to western countries. At present, shaanxi institute of machinery design and xi 'an jiaotong university in liquid rocket engine turbine dynamic-static pressure bearing technology has certain research and achieved certain results. Shaanxi machinery design institute proposed the use of dynamic and static pressure on the liquid rocket engine bearing principle, and the work of the oxygen of the radial and thrust bearings for the object, through theoretical calculation, the combination of dynamic and static pressure bearing selection principle and turbine pump development experience, designate: choose from many kinds of structure forms the radial appropriate chooses cavity of dynamic and static pressure radial bearing, thrust bearing xuan choose spiral groove structure or form of tile type. At the same time also to the cavity of dynamic and static pressure radial bearing is researched, and the bearing is symmetric structure, four oil cavity diameter of 30 mm, 56 RMS radius clearance, test load of 9. 6 kg, were conducted three times running test, speed 500 r/min to 6000 r/min respectively and 6000 ~ 18000 r/min, the results show that no obvious wear phenomenon.