High-energy rotor uncontained failure can cause catastrophic damage effects to aircraft systems if not addressed in design. In this paper, numerical simulations of three high-energy rotor disk fragments impacting on U...High-energy rotor uncontained failure can cause catastrophic damage effects to aircraft systems if not addressed in design. In this paper, numerical simulations of three high-energy rotor disk fragments impacting on U type protection rings are carried out using LS-DYNA. Protection rings with the same mass and different groove depths are designed to study the influence of the groove depth. Simulation results including kinetic energy and impact force variation of single frag- ment are presented. It shows that the groove depth infects both the axial containment ability of the protection ring and the transfer process of energy. The depth of groove ought to be controlled to an appropriate value to meet both the requirement of axial containment and higher safety factor. Ver- ification test on high-speed spin tester has been conducted and shows that protection ring with appropriate U structure can resist the impact of the disk burst fragments. The ring is inflated from a circular to an oval-triangle shape. The corresponding simulation shows good agreement with the test.展开更多
Ground based, wind energy extraction systems have reached their maximum capability. The limitations of current de-signs are: wind instability, high cost of installations, and small power output of a single unit. The w...Ground based, wind energy extraction systems have reached their maximum capability. The limitations of current de-signs are: wind instability, high cost of installations, and small power output of a single unit. The wind energy industry needs of revolutionary ideas to increase the capabilities of wind installations. This article suggests a revolutionary innovation which produces a dramatic increase in power per unit and is independent of prevailing weather and at a lower cost per unit of energy extracted. The main innovation consists of large free-flying air rotors positioned at high altitude for power and air stream stability, and an energy cable transmission system between the air rotor and a ground based electric generator. The air rotor system flies at high altitude up to 14 km. A stability and control is provided and systems enable the changing of altitude. This article includes six examples having a high unit power output (up to 100 MW). The proposed examples provide the following main advantages: 1) Large power production capacity per unit—up to 5,000 - 10,000 times more than conventional ground-based rotor designs;2) The rotor operates at high altitude of 1 - 14 km, where the wind flow is strong and steady;3) Installation cost per unit energy is low;4) The installation is environmentally friendly (no propeller noise).展开更多
文摘High-energy rotor uncontained failure can cause catastrophic damage effects to aircraft systems if not addressed in design. In this paper, numerical simulations of three high-energy rotor disk fragments impacting on U type protection rings are carried out using LS-DYNA. Protection rings with the same mass and different groove depths are designed to study the influence of the groove depth. Simulation results including kinetic energy and impact force variation of single frag- ment are presented. It shows that the groove depth infects both the axial containment ability of the protection ring and the transfer process of energy. The depth of groove ought to be controlled to an appropriate value to meet both the requirement of axial containment and higher safety factor. Ver- ification test on high-speed spin tester has been conducted and shows that protection ring with appropriate U structure can resist the impact of the disk burst fragments. The ring is inflated from a circular to an oval-triangle shape. The corresponding simulation shows good agreement with the test.
文摘Ground based, wind energy extraction systems have reached their maximum capability. The limitations of current de-signs are: wind instability, high cost of installations, and small power output of a single unit. The wind energy industry needs of revolutionary ideas to increase the capabilities of wind installations. This article suggests a revolutionary innovation which produces a dramatic increase in power per unit and is independent of prevailing weather and at a lower cost per unit of energy extracted. The main innovation consists of large free-flying air rotors positioned at high altitude for power and air stream stability, and an energy cable transmission system between the air rotor and a ground based electric generator. The air rotor system flies at high altitude up to 14 km. A stability and control is provided and systems enable the changing of altitude. This article includes six examples having a high unit power output (up to 100 MW). The proposed examples provide the following main advantages: 1) Large power production capacity per unit—up to 5,000 - 10,000 times more than conventional ground-based rotor designs;2) The rotor operates at high altitude of 1 - 14 km, where the wind flow is strong and steady;3) Installation cost per unit energy is low;4) The installation is environmentally friendly (no propeller noise).
