Test facility for transient operation point changes of hydraulic machinery

The effect of transient operation on the hydrodynamic performance of a centrifugal pump impeller was investigated experimentally. All experiments were conducted in the Naval Undersea Warfare Center’s Impeller Test Facility (ITF), which was designed and built for transient and steady-state operation impeller research. The ITF provides transient operation through simultaneous control of both impeller rotational speed and flow rate over time. The impeller was accelerated from rest with peak angular accelerations up to 720 radians/s2 and inlet flow mean accelerations up to 1.7 g, reaching a peak rotational speed of 2400 rpm and a flow rate of 416 l/s. The impeller was then decelerated to rest. Results showed substantial transient effects in overall impeller performance and demonstrated that the quasisteady assumptions commonly used for the design of impellers that operate under high transient (accelerating or decelerating) conditions are not valid.

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Radiation Damage Studies with the HVEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096655 ◽

1972 ◽

Vol 30 ◽

pp. 680-681

Author(s):

J. J. Laidler ◽

B. Mastel

Keyword(s):

Radiation Damage ◽

Stainless Steels ◽

Volume Expansion ◽

Austenitic Stainless Steels ◽

Test Facility ◽

Fast Breeder Reactors ◽

Breeder Reactors ◽

Under Construction ◽

Development Laboratory ◽

Insight Into

One of the major materials problems encountered in the development of fast breeder reactors for commercial power generation is the phenomenon of swelling in core structural components and fuel cladding. This volume expansion, which is due to the retention of lattice vacancies by agglomeration into large polyhedral clusters (voids), may amount to ten percent or greater at goal fluences in some austenitic stainless steels. From a design standpoint, this is an undesirable situation, and it is necessary to obtain experimental confirmation that such excessive volume expansion will not occur in materials selected for core applications in the Fast Flux Test Facility, the prototypic LMFBR now under construction at the Hanford Engineering Development Laboratory (HEDL). The HEDL JEM-1000 1 MeV electron microscope is being used to provide an insight into trends of radiation damage accumulation in stainless steels, since it is possible to produce atom displacements at an accelerated rate with 1 MeV electrons, while the specimen is under continuous observation.

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