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Results for “SHROUD”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
NASA NTRS1994

Some metallographic results for brush bristles and brush segments of a shroud ring brush seal tested in a T-700 engine

Post-test investigation of a T-700 engine brush seal found regions void of bristles ('yanked out'), regions of bent-over bristles near the inlet, some 'snapped' bristles near the fence, and a more uniform smeared bristle interface between the first and last axial rows of bristles. Several bristles and four brush segments were cut from the brush seal, wax mounted, polished, and analyzed. Metallographic analysis of the bristle near the rub tip showed tungsten-rich phases uniformly distributed throughout the bristle, no apparent change within 1 mu m of the interface, and possibly a small amount of titanium, which would represent a transfer from the rotor. Analysis of the bristle wear face showed nonuniform tungsten, which is indicative of material resolidification. The cut end contained oxides and internal fractures; the worn end was covered with oxide scale. Material losses due to wear and elastoplastic deformation within the shear zone and third-body lubrication effects in the contact zone are discussed.

Hendricks, Robert C.↗
NASA NTRS1994

Modeling the effect of shroud contact and friction dampers on the mistuned response of turbopumps

The contract has been revised. Under the revised scope of work a reduced order model has been developed that can be used to predict the steady-state response of mistuned bladed disks. The approach has been implemented in a computer code, LMCC. It is concluded that: the reduced order model displays structural fidelity comparable to that of a finite element model of an entire bladed disk system with significantly improved computational efficiency; and, when the disk is stiff, both the finite element model and LMCC predict significantly more amplitude variation than was predicted by earlier models. This second result may have important practical ramifications, especially in the case of integrally bladed disks.

Griffin, Jerry H.↗
NASA NTRS1995

Metallographic Analysis of Brush Bristle and Integrity Testing of Brush Seal in Shroud Ring of T-700 Engine

Post-test investigation of a T-700 engine brush seal found regions void of bristles ('yanked out'), regions of bent-over bristles near the inlet, some 'snapped' bristles near the fence, and a more uniform 'smeared' bristle interface between the first and last axial rows of bristles. Several bristles were cut from the brush seal, wax mounted, polished, and analyzed. Metallographic analysis of the bristles near the rub tip showed tungsten-rich phases uniformly distributed throughout the bristle with no apparent change within 1 to 2 micron of the interface except for possibly a small amount of titanium, which would represent a transfer from the rotor. Analysis of the bristle wear face showed nonuniform tungsten, which is indicative of material resolidification. The cut end contained oxides and internal fractures; the worn end was covered with oxide scale. Material losses due to wear and elastoplastic deformation within the shear zone and third-body lubrication effects in the contact zone are discussed.

Hendricks, Robert C.↗
NASA NTRS2001

Energy Absorbing Protective Shroud

The present invention is a dissipating protection energy system designed to receive and safely dissipate the kinetic energy from high energy fragments. The energy dissipation system dissipates energy transferred to it by the incremental and progressive rupturing at an approximately constant force of strategically placed sacrificial stitching applied to a number of high strength straps, such as an aromatic polyimide fiber of extremely high tensile strength. Thus, the energy dissipation system provides a lightweight device for controlling and dissipating the dangerous and destructive energy stored in high strength fragments released by catastrophic failures of machinery minimizing damage to other critical components.

Schneider, William C.↗
NASA NTRS1985

Rub tolerant shroud

A seal structure between first and second relatively moveable members for preventing gas flow in the space between the members and transverse to their general direction of motion is disclosed. The seal structure includes a plurality of substantially parallel strips within 30.degree. of normal to the radial plane generally containing these first and second relatively moveable members. The strips are thin and closely spaced and arranged so that one strip edge is attached to the first member and another edge is free to resiliently deflect when in rubbing contact with the second member.

Gay, Jr., Charles H.↗
DOE OSTI2014

Turbine airfoil to shroud attachment method

Bi-casting a platform (50) onto an end portion (42) of a turbine airfoil (31) after forming a coating of a fugitive material (56) on the end portion. After bi-casting the platform, the coating is dissolved and removed to relieve differential thermal shrinkage stress between the airfoil and platform. The thickness of the coating is varied around the end portion in proportion to varying amounts of local differential process shrinkage. The coating may be sprayed (76A, 76B) onto the end portion in opposite directions parallel to a chord line (41) of the airfoil or parallel to a mid-platform length (80) of the platform to form respective layers tapering in thickness from the leading (32) and trailing (34) edges along the suction side (36) of the airfoil.

17 WIND ENERGY↗
DOE OSTI2019

Apparatus, turbine nozzle and turbine shroud

Apparatuses are disclosed including a first article, a second article, a sewing member and a thermal break. The second article includes a second material composition having a second thermal tolerance greater than a first thermal tolerance of a first material composition of the first article. The sealing member is disposed between and contacts the first article and the second article, and includes a third material composition having a third thermal tolerance less than the second thermal tolerance and less than an operating temperature of the second article. The thermal break is defined by the second article, and is proximate to the sealing member and partitioned from the sealing member by a portion of the second article. The thermal break interrupts a thermal conduction path from the second article to the sealing member. The first article and the second article compress the sealing member, forming a thermal gradient-tolerant seal.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Refining Absorber Shroud Geometry to Maximize Power Output and Reduce Power Peaking in ATF Test Train

In the wake of the Fukushima Daiichi nuclear power plant accident in 2011, the accident tolerant fuels (ATF) program was initiated to enhance the safety of light-water reactor fuels, placing significant emphasis on cladding. A crucial step for the broad implementation of ATF in commercial reactors involves irradiation testing of the fuel designs. ATF-2D, the latest experiment in the ATF series, is slated to undergo irradiation in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). ATF-2D is a joint effort of the INL with industry partners General Electric Global Research; Framatome; General Atomics; the Japan Atomic Energy Agency; Hitachi-GE Nuclear Energy, Ltd; Global Nuclear Fuel-Japan Co., Ltd; Nippon Nuclear Fuel Development Co., Ltd; and Mitsubishi Heavy Industries, Ltd. The ATF-2D test train design consists of four tiers, each housing six rodlets. The device will be inserted in Loop 2A within the central flux trap of the ATR, and is anticipated to undergo irradiation throughout three 60-day cycles. Typical pressurized water reactor conditions will be emulated during the irradiation. The objective of the work presented here is to dimension neutron-absorbing hafnium (Hf) components surrounding the fuel rodlets, such that the axial power profile is flattened, while simultaneously ensuring that the total fission power output of the entire test train remains below 200 kW.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2024

Refining Absorber Shroud Geometry to Maximize Power Output and Reduce Power Peaking in ATF Test Train

In the wake of the Fukushima Daiichi nuclear power plant accident in 2011, the accident tolerant fuels (ATF) program was initiated to enhance the safety of light-water reactor fuels, placing significant emphasis on cladding. A crucial step for the broad implementation of ATF in commercial reactors involves irradiation testing of the fuel designs. ATF-2D, the latest experiment in the ATF series, is slated to undergo irradiation in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). ATF-2D is a joint effort of the INL with industry partners General Electric Global Research; Framatome; General Atomics; the Japan Atomic Energy Agency; Hitachi-GE Nuclear Energy, Ltd; Global Nuclear Fuel-Japan Co., Ltd; Nippon Nuclear Fuel Development Co., Ltd; and Mitsubishi Heavy Industries, Ltd. The ATF-2D test train design consists of four tiers, each housing six rodlets. The device will be inserted in Loop 2A within the central flux trap of the ATR, and is anticipated to undergo irradiation throughout three 60-day cycles. Typical pressurized water reactor conditions will be emulated during the irradiation. The objective of the work presented here is to dimension neutron-absorbing hafnium (Hf) components surrounding the fuel rodlets, such that the axial power profile is flattened, while simultaneously ensuring that the total fission power output of the entire test train remains below 200 kW.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗