A Neutron Activation Analysis Code

Developed at ITER-India, Institute for Plasma Research

ACTYS Project > ACTYS-1-GO


ACTYS-1-GO is the second code in the family of ACTYS project. In order to solve the activation problem for a huge geometry, a faster algorithm to treat large set of meshes/points is needed. At the heart of ACTYS-1-GO, lies the same working engine as ACTYS. For multi-point calculations, a robust and expansive algortihm is required. Accordingly, a common coefficient matrix is developed and its sparsity is reduced in 3 steps. This specific algorithm is included to make the multipoint calculation faster than other codes in its category. Because of the faster speed, a high spatial resolution can be obtained by using fine mesh. ACTYS-1-GO is validated against FISPACT-EASY 2007 and ATTILA-FORNAX and the results from each code were in good agreement.

ACTYS-1-GO can be easily coupled with known transport codes like ATTILA and MCNP and be used in Rigrous-2-Step method for the calculation of Shutdown Dose Rate (SDDR) and Radwaste classification. It is already coupled with the transport code ATTILA and the coupler is named ACTYS-ASG. The module reads ATTILA input and geometry file to scan geometry details and material composition. It also reads the report file generated by ATTILA to get the neutron flux at each mesh point. After the activation is complete, the code generates a 42-group gamma source file, which can be read by ATTILA to perform the SDDR calculations.

The above animation is the variation of Contact Dose rate in time as calculated by ACTYS-ASG for the Iter SDRB benchmark problem ref {M. Loughlin, Conclusion of shutdown dose rate benchmark study, Tech. rep., ITER, 6th ITER Neutronics Meeting,Hefei, China, june 17-24 (2011)}. The units are Sv/hr and the color scale is logarithmic. The dose from the endplate is monitored till it decays down to the background radiation level. The flux file for the problem is generated using ATTILA. The activation calculation at 2085 mesh points in the endplate of the geometry for 62 time steps took 4 min. With average speed of 8 mesh/sec.