Effect of the protrusion shape on gas ingestion of two sealing structures

The windage loss caused by protrusion in a rotor–stator cavity has been studied in detail,and there are abundant fitting formulas that have been summarized to calculate the moment coefficients.Some other theorists have emphasized its effect on the sealing efficiency,proposing that installation of protrusion could alleviate gas ingestion.However,the protrusion shape which is an influential factor on the sealing efficiency has not been focused in previous research.Using the experimental method of measuring CO2 volume fraction,cavity pressure,and power consumption,we investigated the effects of several typical protrusion shapes on various parameters for two sealing structures,in order to obtain the optimal shape.Results showed that a variation of the protrusion shape had little impact on the static pressure,but the total pressure and the sealing efficiency increased in different degrees.Furthermore,even though the hexagon shape resulted in the highest sealing efficiency,we observed that the drop shape had the best overall performance in all of the eight models,which could result in higher efficiency of the turbine cavity.The combination of a radial seal structure and protrusion could improve sealing efficiency better.

AutoTrak 475系列旋转导向仪器下轴Seal Carrier组装工具设计与应用

现有AutoTrak 475系列旋转导向仪器下轴“Seal Carrier”的组装存在质量隐患,压入过程可能损坏“Axial Seal”且维保人员难以察觉。为避免此类问题,设计加工维保工装并修改维保流程,使维保人员能掌握“Axial Seal”状态,杜绝盲目挤压造成的破坏,提高了仪器可靠性。新工装配合已有工装使用,将“Seal Sleeve”先安装至“Seal Carrier”内部再整体加热至95℃热装至下轴,同时明确了新工装使用注意事项。经风险验证可行,新工装使用可直接节约50万元配件成本。