On the Resonance Instability of EBR-1 (in Japanese)
The experimental Breeder Reactor, EBR-1, received considerable attention when an oscillatory instability under abnormal operating conditions was observed. Investigations of kinetic characteristics revealed that a prompt positive power coefficient of reactivity, which is generally believed due to the bowing of fuel elements, and a more delayed negative power coefficient exist. Controlled oscillator measurements were performed with the result that EBR-1 exhibited resonance instability. Though a number of theoretical models of the coefficients was presented to study the instability, they do not fit the mechanism of the delayed negative coefficient. The models of feedback reactivity for Mark II and Mark III core loading are presented. For Mark II, the main point to be emphasized is the cause of time delay by heat transfer from the core to the structure. The delayed negative reactivity is treated by a transfer function that takes into account axial temperature distribution in the core. It is demonstrated that the delayed negative reactivity combined with the prompt positive reactivity is sufficient to permit the resonance instability. For Mark III, the frequency transfer functions of feedback reactivity were separated from the experiment. The model is compared with the result of measurements.
- Research Organization:
- Tokyo Institute of Technology (Japan)
- Sponsoring Organization:
- USDOE
- NSA Number:
- NSA-15-030282
- OSTI ID:
- 4841185
- Journal Information:
- Nippon Genshiryoku Gakkai-Shi, Vol. 3, Issue 7; Other Information: Orig. Receipt Date: 31-DEC-61; ISSN 0004-7120
- Country of Publication:
- Country unknown/Code not available
- Language:
- Japanese
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