CALIBRATION AND DESIGN OPTIMIZATION OF A NUCLEAR-SURFACE MOISTURE-DENSITY GAUGE BY MONTE-CARLO SIMULATION

The application of analytical methods to the solution of radiation tra nsport problems is not feasible for the complicated geometries found i n most cases of practical interest. The design and calibration of a nu clear gauge can be successfully assisted by computerized Monte Carlo s imulation techniques. This paper reports the results of numerical calc ulations obtained using the MCNP code to simulate a neutron-gamma-ray surface gauge for moisture and density measurements. Good agreement be tween experimental and calculated calibration curves has been obtained . An optimization study has been carried out to improve the gauge perf ormance through an adequate choice of the spatial arrangement of gauge components and the utilization of shielding materials.