Research output: Contribution to journal › Article › peer-review
Nuclear heating measurements by gamma and neutron thermometers. / Van Nieuwenhove, Rudi; Vermeeren, Ludo.
In: EPJ Web of Conferences, Vol. 225, 04003, 22.01.2020, p. 1-6.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Nuclear heating measurements by gamma and neutron thermometers
AU - Van Nieuwenhove, Rudi
AU - Vermeeren, Ludo
N1 - Score=10
PY - 2020/1/22
Y1 - 2020/1/22
N2 - A gamma thermometer suitable for very high gamma heating levels (up to 20 W/g) has been designed and modelled by means of detailed finite element calculations. Based on a sensitivity analysis, the predicted accuracy of this gamma thermometer is better than 5 %. A novel miniaturized gamma thermometer is proposed in which a single thermocouple is used as the gamma absorption element, allowing a reduction of the sensor diameter down to 3 mm. Monte Carlo calculations (by MCNP) have been performed to assess the relative contribution of neutrons to the nuclear heating in a gamma thermometer. Calculations have been performed for gamma thermometers with an inner body made of various materials, such as stainless steel, tungsten, molybdenum and rhodium. By using gamma thermometers made of different materials, it will be possible to deduce the nuclear heating rates in these materials and also to separate out the neutron and gamma heating contributions. The Monte Carlo calculations show that nuclear heating of rhodium is mainly due to neutrons, converting the rhodium gamma thermometer effectively in a neutron thermometer. The sensitivities of the gamma thermometers with W, Mo or Rh as heated materials have been modelled by finite element calculations. It is found that both the Mo and the Rh based sensor have a very linear response up to a nuclear heating of 20 W/g.
AB - A gamma thermometer suitable for very high gamma heating levels (up to 20 W/g) has been designed and modelled by means of detailed finite element calculations. Based on a sensitivity analysis, the predicted accuracy of this gamma thermometer is better than 5 %. A novel miniaturized gamma thermometer is proposed in which a single thermocouple is used as the gamma absorption element, allowing a reduction of the sensor diameter down to 3 mm. Monte Carlo calculations (by MCNP) have been performed to assess the relative contribution of neutrons to the nuclear heating in a gamma thermometer. Calculations have been performed for gamma thermometers with an inner body made of various materials, such as stainless steel, tungsten, molybdenum and rhodium. By using gamma thermometers made of different materials, it will be possible to deduce the nuclear heating rates in these materials and also to separate out the neutron and gamma heating contributions. The Monte Carlo calculations show that nuclear heating of rhodium is mainly due to neutrons, converting the rhodium gamma thermometer effectively in a neutron thermometer. The sensitivities of the gamma thermometers with W, Mo or Rh as heated materials have been modelled by finite element calculations. It is found that both the Mo and the Rh based sensor have a very linear response up to a nuclear heating of 20 W/g.
KW - Nuclear measurements
KW - Gamma-ray
KW - detectors
UR - http://ecm.sckcen.be/OTCS/llisapi.dll/open/37188117
U2 - 10.1051/epjconf/202022504003
DO - 10.1051/epjconf/202022504003
M3 - Article
VL - 225
SP - 1
EP - 6
JO - EPJ Web of Conferences
JF - EPJ Web of Conferences
SN - 2100-014X
M1 - 04003
T2 - 2019 - ANIMMA - Advancements in Nuclear Instrumentation Measurement Methods and their Applications
Y2 - 17 June 2019 through 21 June 2019
ER -
ID: 6745676