The principle and characteristics of hydrostatic gas lubricated non-contacting mechanical seal (HSGLNMS) are introduced. The flow field of the gas film is established by numerical analysis of end faces of HSGLNMS. T...The principle and characteristics of hydrostatic gas lubricated non-contacting mechanical seal (HSGLNMS) are introduced. The flow field of the gas film is established by numerical analysis of end faces of HSGLNMS. The distribution of gas film pressure and seal performance parameters inclu- ding opening force and leakage are obtained. Influence of operating parameters and sealing configu- ration on the sealing performance is studied. HSGLNMS has been designed and manufactured. Its working film thickness and leakage are measured to verify the theoretical analysis. The investigation results show that HSGLNMS demonstrates good speed adaptability, which means that the seal runs successfully with both low and high speed, showing excellent performance. The seal can be regula- ted and controlled online ; the opening force will not be raised greatly with the increasing of the num- ber of throttle orifices, but the leakage of seal increases apparently ; the uniform pressure groove im- proves the sealing performance, for example, opening force and stiffness are raised obviously. While leakage is reduced. Finally, the theoretical analysis is verified by experiment.展开更多
The objective of this investigation was to study whether it is possible to determine the air tightness of covered slurry storage tanks using tracer gas technique by injection of sulphur hexafluoride (SF6) and measur...The objective of this investigation was to study whether it is possible to determine the air tightness of covered slurry storage tanks using tracer gas technique by injection of sulphur hexafluoride (SF6) and measurements of the decay in gas concentrations with an infrared spectrophotometer in the air space above the slurry. By measuring the decay in concentration of injected tracer gas at different occasions, the air exchange rate was determined. Three different types of coverings were studied namely; wooden roof, plastic tent and concrete roof.展开更多
The thermoelastohydrodynamic performance of an inclined-ellipse dimpled gas face seal is analyzed. The pressure distributions of the gas film and temperature fields of the seal rings and gas film are presented conside...The thermoelastohydrodynamic performance of an inclined-ellipse dimpled gas face seal is analyzed. The pressure distributions of the gas film and temperature fields of the seal rings and gas film are presented considering thermal and elastic distortions.Then, the influences of texturing parameters, including dimple inclination angle and dimple depth, on sealing performance are investigated under different operating parameters such as rotational speeds and seal pressures. The results show that face distortions lead to a decrease in the hydrodynamic effect at high rotational speed. The analysis shows that the opening force can decrease by more than 50% as the rotational speed increases from 0 to 35000 r min^(-1). The influence of face distortion on the seal performance, such as opening force and leakage characteristic, gradually increases with the rotational speed.展开更多
基金Supported by the National Natural Science Foundation of China ( No. 50635010 ) and the National Key Basic Research Program of China (2012CB026000).
文摘The principle and characteristics of hydrostatic gas lubricated non-contacting mechanical seal (HSGLNMS) are introduced. The flow field of the gas film is established by numerical analysis of end faces of HSGLNMS. The distribution of gas film pressure and seal performance parameters inclu- ding opening force and leakage are obtained. Influence of operating parameters and sealing configu- ration on the sealing performance is studied. HSGLNMS has been designed and manufactured. Its working film thickness and leakage are measured to verify the theoretical analysis. The investigation results show that HSGLNMS demonstrates good speed adaptability, which means that the seal runs successfully with both low and high speed, showing excellent performance. The seal can be regula- ted and controlled online ; the opening force will not be raised greatly with the increasing of the num- ber of throttle orifices, but the leakage of seal increases apparently ; the uniform pressure groove im- proves the sealing performance, for example, opening force and stiffness are raised obviously. While leakage is reduced. Finally, the theoretical analysis is verified by experiment.
文摘The objective of this investigation was to study whether it is possible to determine the air tightness of covered slurry storage tanks using tracer gas technique by injection of sulphur hexafluoride (SF6) and measurements of the decay in gas concentrations with an infrared spectrophotometer in the air space above the slurry. By measuring the decay in concentration of injected tracer gas at different occasions, the air exchange rate was determined. Three different types of coverings were studied namely; wooden roof, plastic tent and concrete roof.
基金supported by the National Natural Science Foundation of China(Grant No.51275473)the Zhejiang Provincial Natural Science Foundation of China(Grant No.LR14E050001)
文摘The thermoelastohydrodynamic performance of an inclined-ellipse dimpled gas face seal is analyzed. The pressure distributions of the gas film and temperature fields of the seal rings and gas film are presented considering thermal and elastic distortions.Then, the influences of texturing parameters, including dimple inclination angle and dimple depth, on sealing performance are investigated under different operating parameters such as rotational speeds and seal pressures. The results show that face distortions lead to a decrease in the hydrodynamic effect at high rotational speed. The analysis shows that the opening force can decrease by more than 50% as the rotational speed increases from 0 to 35000 r min^(-1). The influence of face distortion on the seal performance, such as opening force and leakage characteristic, gradually increases with the rotational speed.