ISSN:
1573-8205
Source:
Springer Online Journal Archives 1860-2000
Topics:
Energy, Environment Protection, Nuclear Power Engineering
,
Physics
Notes:
Conclusions The experimental investigations and calculations of slit configurations in iron and iron—water shielding enable the following conclusions to be drawn. 1. The results of calculations using the BLANK and MCNP programs of the distribution of the reaction rates of four threshold detectors representing characteristic groups of neutrons in the range 1–14 MeV are in agreement with experiment within a 20% error both over the thickness of the shielding compositions and on their rear surface in a direction transverse to the slit. This gives grounds for supposing that in reactor calculations for the shielding thickness considered the spectral components of the neutron flux are correctly reproduced in estimates of heating caused by neutrons and of the neutron dose behind a similar shielding with slits. 2. Calculations of the distribution of the absorbed γ-radiation dose rate in solid shielding made of iron and compositions and having a 20-mm wide straight slit in iron and iron—water shielding agree within 20% with measurements using thermoluminescent detectors in iron in the assembly volume and at its rear surface. 3. When estimating the characteristic dimensions of the effects of introducing slit gaps into solid shielding made of 400-mm thick iron (and also in an iron—water composition) it can be noted that the presence of a even a 5-mm wide straight longitudinal slit in the mode configuration considered, with a neutron source on its axis, leads to an increase in the flux of source neutrons at the exit from the slit by a factor of 100 relative to that for solid shielding. The effect of the slit for the γ-radiation absorbed dose rate is considerably smaller than for fast neutrons and amounts to a factor of 4–5 increase in the dose at the exit from the slit compared with the value for solid shielding. 4. An important conclusion of the work is the necessity of improving the experimental method for measuring the heating caused by neutrons and γ-radiation, and also the development of new measurement methods which do not rely on calculated data.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02359933
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