EVALUASI PERILAKU SWELLING IRADIASI BAHAN BAKAR RSG−GAS

ABSTRAK EVALUASI PERILAKU SWELLING IRADIASI BAHAN BAKAR RSG-GAS. Telah dilakukan evaluasi terhadap perilaku swelling iradiasi bahan bakar RSG-GAS. Evaluasi dimaksudkan untuk mendukung program perbaikan daya- guna bahan bakar melalui peningkatan derajat bakar bahan bakar setinggi mungkin. Bahan bakar yang dievaluasi adalah bahan bakar uranium pengayaan rendah tipe dispersi U 3 Si 2 -Al (2,96 gr U/cm 3 ) bentuk pelat lurus ( MTR box shape fuel element ). Evaluasi didasarkan atas data hasil perhitungan program komputer DART untuk iradiasi kondisi tunak pada daya nominal RSG-GAS (30 MW termal). Hingga derajat bakar mencapai sekitar 100% U 235 , efek swelling iradiasi untuk iradiasi kondisi tunak terhadap integritas mekanik kelongsong dan unjuk kerja termik bahan bakar dapat diabaikan (masih dalam batas toleransi disain). Hal ini menunjukkan bahwa pada dasarnya bahan bakar silisida yang digunakan RSG-GAS saat ini dapat diiradiasi hingga derajat bakar mencapai 100% U 235 terbakar. KATA KUNCI: Swelling , Iradiasi, Bahan bakar dispersi U 3 Si 2 -Al, Uranium pengayaan rendah, Program komputer DART ABSTRACT EVALUATION OF IRRADIATION SWELLING BEHAVIOUR OF RSG-GAS FUEL. Evaluation of irradiation swelling behaviour of RSG-GAS fuel has been performed. The evaluation is intended to support the fuel utilization improvement program by increasing the fuel discharge burnup as high as possible. Fuel that has been evaluated is dispersion type of low enriched uranium of U 3 Si 2 -Al (2.96 gr U/cm 3 ) in the form of straight plate (MTR box shape fuel element). The evaluation is based on DART calculation results for steady-state irradiation at RSG-GAS nominal power (30 MW thermal). Up to fuel burnup of 100% U 235 , the effect of fuel swelling for steady state irradiation on the mechanical integrity of fuel cladding and the thermal performance of the fuel can be ignored (within the design tolerance). This indicates that the silicide fuel being used in RSG-GAS basically can be irradiated until fuel burnup as high as 100% U 235 . FREE TERMS: Swelling, Irradiation, U 3 Si 2 -Al dispersion fuel, Low enriched uranium, DART computer program