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Nano to begin drilling next week in Illinois
It’s been a good month for Nano Nuclear in the state of Illinois. On October 7, the Office of Governor J.B. Pritzker announced that the company would be awarded $6.8 million from the Reimagining Energy and Vehicles in Illinois Act to help fund the development of its new regional research and development facility in the Chicago suburb of Oak Brook.
S. Bian
Nuclear Technology | Volume 41 | Number 3 | December 1978 | Pages 401-407
Technical Note | Reactor | doi.org/10.13182/NT78-A32124
Articles are hosted by Taylor and Francis Online.
A rod ejection accident introduces a large positive reactivity insertion in a core, causing a large power excursion. The point kinetics method is usually used to analyze this type of accident. The reactivity changes due to Doppler effect are usually obtained by static neutronics calculations with nominal (pre-ejection) core flux shapes for different fuel temperatures. The effect of locally peaked shapes due to the rod ejection is not included in the Doppler reactivity calculation. The resultant Doppler reactivity feedback is considerably underestimated, while the magnitude of the power excursion is overestimated. A simplified method that incorporates the local flux peaking effect on the Doppler feedback in a point kinetics code has been developed. The results based on this weighted Doppler feedback compare favorably with a three-dimensional kinetics analysis.