An experimental study is performed to investigate the temperature response and distribution in a sector tilted pad thrust bearing during the transient periods such as the load on the bearing changed abruptly.Lots of t...An experimental study is performed to investigate the temperature response and distribution in a sector tilted pad thrust bearing during the transient periods such as the load on the bearing changed abruptly.Lots of thermocouples are placed on different position such as the pad surface,leading and trailing edge as well as the pad block,and then these thermocouples are used to measure the temperature variation during the transient period.The load on one pad and the displacement of the runner are measured with different sensors.The effects of a sudden load change on temperature at different position of the pads are analyzed according to the experimental data.The influence of different initial conditions and the different load increment on temperature variation at the pad surface and pad body are obtained,and temperature responses at leading edge and trailing edge under different conditions are tested.This experimental study shows a significant effect of load increment and initial condition on the temperature distribution of bearing pad interface under sudden load change conditions,and the measurement of real oil film temperature is difficult due to the large thermal inertia of pad surface.展开更多
Based on the mathematical model of one dimension transient flow of the polymer foam in porous media, the numerical calculation method of the flow mentioned above by using the finite difference method is given. Through...Based on the mathematical model of one dimension transient flow of the polymer foam in porous media, the numerical calculation method of the flow mentioned above by using the finite difference method is given. Through the experiments of one dimension transient flow of HPAM (Hydrolytic Polyacrylamide) foam in the artificial sandstone core, the HPAM foam generation and coalescence coefficient of the mathematical model mentioned above are determined. The profiles of the liquid phase saturation, the pressure drop and the number density of one dimension transient flow of HPAM foam with the dimensionless time in artificial sandstone core are numerically calculated and analyzed by using the numerical calculation method.展开更多
为了研究底排点火具在弹丸出炮口时瞬态燃烧特性及工作性能,采用半密闭爆发器模拟炮口压力突降过程,借助高速录像系统,开展了高降压速率条件下底排点火具燃烧特性的实验研究。结果表明,在高速降压过程中,底排点火具燃烧受到强烈瞬态扰...为了研究底排点火具在弹丸出炮口时瞬态燃烧特性及工作性能,采用半密闭爆发器模拟炮口压力突降过程,借助高速录像系统,开展了高降压速率条件下底排点火具燃烧特性的实验研究。结果表明,在高速降压过程中,底排点火具燃烧受到强烈瞬态扰动。不同药剂的点火具抗干扰性能不同,其中以硝酸钡为药剂主成分的点火具和以镁粉+PTFE为药剂主成分的点火具燃烧性能稳定,以氢化锆、二氧化铅为药剂主成分的点火具工作稳定性较差,火焰持续时间标准差为523 m s,点火具喷孔堵塞严重。展开更多
文摘An experimental study is performed to investigate the temperature response and distribution in a sector tilted pad thrust bearing during the transient periods such as the load on the bearing changed abruptly.Lots of thermocouples are placed on different position such as the pad surface,leading and trailing edge as well as the pad block,and then these thermocouples are used to measure the temperature variation during the transient period.The load on one pad and the displacement of the runner are measured with different sensors.The effects of a sudden load change on temperature at different position of the pads are analyzed according to the experimental data.The influence of different initial conditions and the different load increment on temperature variation at the pad surface and pad body are obtained,and temperature responses at leading edge and trailing edge under different conditions are tested.This experimental study shows a significant effect of load increment and initial condition on the temperature distribution of bearing pad interface under sudden load change conditions,and the measurement of real oil film temperature is difficult due to the large thermal inertia of pad surface.
文摘Based on the mathematical model of one dimension transient flow of the polymer foam in porous media, the numerical calculation method of the flow mentioned above by using the finite difference method is given. Through the experiments of one dimension transient flow of HPAM (Hydrolytic Polyacrylamide) foam in the artificial sandstone core, the HPAM foam generation and coalescence coefficient of the mathematical model mentioned above are determined. The profiles of the liquid phase saturation, the pressure drop and the number density of one dimension transient flow of HPAM foam with the dimensionless time in artificial sandstone core are numerically calculated and analyzed by using the numerical calculation method.
文摘为了研究底排点火具在弹丸出炮口时瞬态燃烧特性及工作性能,采用半密闭爆发器模拟炮口压力突降过程,借助高速录像系统,开展了高降压速率条件下底排点火具燃烧特性的实验研究。结果表明,在高速降压过程中,底排点火具燃烧受到强烈瞬态扰动。不同药剂的点火具抗干扰性能不同,其中以硝酸钡为药剂主成分的点火具和以镁粉+PTFE为药剂主成分的点火具燃烧性能稳定,以氢化锆、二氧化铅为药剂主成分的点火具工作稳定性较差,火焰持续时间标准差为523 m s,点火具喷孔堵塞严重。
