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MIRENE is a MIni nuclear REactor for NEutronography. In the first part of this paper MIRENE is described and its characteristics are given. The core uses only 1 kg of enriched uranium in solution state. It works in a self-limited pulse mode. The neutron pulses are collimated in two beams which cross the concrete pro-tection walls surrounding the reactor. The main characteristics are :
. peak power : 161 kW
. exponential rise time : .87 sec
. overall energy in a pulse : 2.9 MJ (6.8 x 1016 fissions)
. axial beam :
- exposure aera : 30 cm x 30 cm
- useful fluence per pulse : thermal neutrons : 9 x 108 n/cm2 ; γ-rays : 22 rads (Cd ratio on gold detector : 2)
. lateral beam :
- exposure aera : 18 cm x 24 cm
- useful fluence per pulse : thermal neutrons : 2.6 x 108 n/cm2 ; γ-rays : . 7 rad (Cd ratio : 9).
In the second part of the paper, many applications of MIRENE in much different fields are indicated. The results we have obtained since MIRENE started to operate, in 1977, are shown :
- In nuclear engineering :.testing of first neutron reactor fuel-pins .control of "neutrophage screens" used in transport and storage of nuclear-fuel materials to secure the criticity-safety .observation of irradiated-oxyde samples in order to determine the Equation of State of the fuel used in fast-neutron reactors .observation of UO2-H20 mixing conditions in the field of cri-ticity experiments
- In engineering, MIRENE has a large field of applications, two examples are given : . the control of the sealing of an electric isolator . the visualization of the bonding layer between two high density metals
- Finally we show an original application in agronomy which has given very good results : the observation of the in-situ-growth of a corn-root.
All these results prove that MIRENE as well as similar reactors can bring about an important contribution as Non-Destructive-Testing stools in the most large field of applications. Their simplicity of design and working connected to their intrinsic safety enabled them to have a high competitive performance/cost ratio. Users can take advantage of the own performances of nuclear reactors in neutronography while being relieved of a large part of the constraints associated to large-size ordinary reactor installation.
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