1. The use of MCNP code in APEX fusion reactor technology

In this study, new APEX hybrid model was developed by the way of using the APEX fusion technology. The superiority of the APEX fusion technology from the other fusion technologies is that a fluid wall was used in reactor, which flows instead the first solid wall. The advantage of this fluid wall is to extend the life the structural material of the reactor by reducing the rate of damage on the structrual material.It also allows high neutron wall loads.The meausures for the APEX hybrid model has been taken from the ARIE-RS reactor design which was made in the framework of studies.In the APEX studies, the conventional first solid wall facing with the plasma is replaced with fast flowing thin liquid wall layer. Free-surface first liquid wall concept is a revolutionary concept. The first liquid wall flows very fast and detains charged particles, and followed by the thick liquid wall (blanket) which flows slowly and absorbs generated energy and converts it to heat. In the study, the flowing molten salt (first wall and blanket) composed of Flibe (Li2BeF4) was considered as the main constituent mixed with different mole fractions (0-12%) of heavy metal salt ThF4 to increase the energy multiplication. Self sufficient Tritium Breeding Ratio (TBR>1,05) has been taken into account to determine the upper limit of the fraction of heavy metal salt in the mixture. Design and calculations of APEX were carried out as 3-D torus by using MCNP-4B computer code. Correspondence/Reprint request: Dr. Aybaba Hançerlioğulları, Kastamonu University, Kastamonu Arts & Sciences Faculty, Physics Dept., 37100 Kastamonu, Turkey. E-mail: aybaba@kastamonu.edu.tr Aybaba Hançerlioğulları 2