Purpose of experiment

The purpose of the experiment is the measurement of relative axial neutron flux distributions in several experimental locations in the core of the JSI TRIGA reactor. This is accomplished through the use of miniature fission chambers with an external diameter of 3 mm, inserted into specially designed guide tubes and a JSI-developed pneumatic positioning system.

Outcome / What you will learn
Students will:
  1. measure axial neutron flux profiles with miniature fission chambers in several different measuring positions and control rod configurations
  2. visualize the effect of the insertion of a control rod on the neutron flux distribution
  3. analyse the shape of the neutron flux profile and compare it with theoretical predictions.

Students perform relative axial fission rate profile measurements in the core of the TRIGA reactor in several radial positions, and compare the measured profiles with theoretical predictions. Features in the measured profiles due to heterogeneity of the reactor fuel are discussed. Measurements are performed with two control rod configurations in order to visualize on the spot the effect of the insertion of a control rod on the neutron flux distribution.

Exercise No. 7: In-core neutron flux mapping