Electro-hydrostatic actuator (EHA) pumps are usually characterized as high speed and small displacement. The tilting inertia moment on the cylinder block produced by the inertia forces of piston/slipper assemblies c...Electro-hydrostatic actuator (EHA) pumps are usually characterized as high speed and small displacement. The tilting inertia moment on the cylinder block produced by the inertia forces of piston/slipper assemblies cannot be ignored when analyzing the cylinder block balance. A large tilting inertia moment will make the cylinder block tilt away from the valve plate, resulting in severe wear and significantly increased leakage. This paper presents an analytical expression for the tilting inertia moment on the cylinder block by means of vector analysis. In addition, a high-speed test rig was built up, and experiments on an EHA pump prototype were carried out at high speeds of up to 10,000 r/min. The predicted nature of the cylinder block tilt at high speeds corresponds closely to the witness marks on the dismantled EHA pump prototype, It is suggested that more attention should be given to the tilting inertia moment acting on the cylinder block of an EHA pump since both wear and leakage flow between the cylinder block and the valve plate are very much dependent on this tilting moment.展开更多
针对高速飞行器大容积、高升力、低阻力和高升阻比的设计需求,提出高压捕获翼(High pressure zone Capture Wing,HCW)的概念.在高速巡航条件下,合理配置HCW可以充分利用来流压缩产生的高压气体,从而提高飞行器升力;HCW采用与来流平行的...针对高速飞行器大容积、高升力、低阻力和高升阻比的设计需求,提出高压捕获翼(High pressure zone Capture Wing,HCW)的概念.在高速巡航条件下,合理配置HCW可以充分利用来流压缩产生的高压气体,从而提高飞行器升力;HCW采用与来流平行的薄板装置,其附加阻力较小,可以大幅提高升阻比.采用CFD分析工具,比较不同容积的乘波体构型与HCW组合前后的气动性能.结果表明,在不同容积构型下升阻比均有明显提高,最小提升量可达10%.此外,容积越大,升力和升阻比增加效果越明显.展开更多
基金the National Basic Research Program of China(No.2014CB046403)the National Natural Science Foundation of China(No.U1509204)for their financial supports
文摘Electro-hydrostatic actuator (EHA) pumps are usually characterized as high speed and small displacement. The tilting inertia moment on the cylinder block produced by the inertia forces of piston/slipper assemblies cannot be ignored when analyzing the cylinder block balance. A large tilting inertia moment will make the cylinder block tilt away from the valve plate, resulting in severe wear and significantly increased leakage. This paper presents an analytical expression for the tilting inertia moment on the cylinder block by means of vector analysis. In addition, a high-speed test rig was built up, and experiments on an EHA pump prototype were carried out at high speeds of up to 10,000 r/min. The predicted nature of the cylinder block tilt at high speeds corresponds closely to the witness marks on the dismantled EHA pump prototype, It is suggested that more attention should be given to the tilting inertia moment acting on the cylinder block of an EHA pump since both wear and leakage flow between the cylinder block and the valve plate are very much dependent on this tilting moment.
文摘针对高速飞行器大容积、高升力、低阻力和高升阻比的设计需求,提出高压捕获翼(High pressure zone Capture Wing,HCW)的概念.在高速巡航条件下,合理配置HCW可以充分利用来流压缩产生的高压气体,从而提高飞行器升力;HCW采用与来流平行的薄板装置,其附加阻力较小,可以大幅提高升阻比.采用CFD分析工具,比较不同容积的乘波体构型与HCW组合前后的气动性能.结果表明,在不同容积构型下升阻比均有明显提高,最小提升量可达10%.此外,容积越大,升力和升阻比增加效果越明显.