著者
山路 昭雄 沼田 茂生 斉藤 鉄夫
出版者
一般社団法人 日本原子力学会
雑誌
日本原子力学会誌 (ISSN:00047120)
巻号頁・発行日
vol.29, no.6, pp.555-563, 1987

A design method is described for the Fe compensational shield which is located around a straight duct in concrete shield wall against γ radiation to compensate the lowering of shielding efficiency caused by the duct. The method has been applied to the configuration, where the source area is not viewed through the duct from the detector point at the duct exit. The form of the compensational shield was determined depending on the wall thickness, the duct diameter, the incident angle of γ-ray beam to the wall, and the densities of the concrete and Fe. An experiment for the compensational shield was performed in the Dry Shielding Facility at JRR-4. The measured dose rates behind the wall were reduced effectively by the compensational shield, so that the maximum dose rates became only slightly higher than that of the bulk shield wall and the dose rates higher than the maximum dose rate for bulk shield wall were restricted only in the area near the duct exit. The experimental results have been analyzed using a multigroup γ-ray single scattering code G33YSN.
著者
山路 昭雄 宮越 淳一 岩男 義明 壺阪 晃 斉藤 鉄夫 藤井 孝良 奥村 芳弘 鈴置 善郎 河北 孝司
出版者
一般社団法人 日本原子力学会
雑誌
日本原子力学会誌 (ISSN:00047120)
巻号頁・発行日
vol.26, no.2, pp.139-156, 1984
被引用文献数
2

Procedures of shielding analysis are described which were used for the shielding modification design of the Nuclear Ship "MUTSU". The calculations of the radiation distribution on board were made using Sn codes ANISN and TWOTRAN, a point kernel code QAD and a Monte Carlo code MORSE.<BR>The accuracies of these calculations were investigated through the analysis of various shielding experiments: the shield tank experiment of the Nuclear Ship "Otto Hahn", the shielding mock-up experiment for "MUTSU" performed in JRR-4, the shielding benchmark experiment using the <SUP>16</SUP>N radiation facility of AERE Harwell and the shielding effect experiment of the ship structure performed in the training ship "Shintoku-Maru". The values calculated by the ANISN agree with the data measured at "Otto Hahn" within a factor of 2 for fast neutrons and within a factor of 3 for epithermal and thermal neutrons. The &gamma;-ray dose rates calculated by the QAD agree with the measured values within 30% for the analysis of the experiment in JRR-4. The design values for "MUTSU" were determined in consequence of these experimental analyses.