The Effect Of Fuel Volume Variation To The Breeding Characteristic Of Passive Compact Molten Salt Reactor (PCMSR)

THE EFFECT OF FUEL VOLUME VARIATION TO THE BREEDING CHARACTERISTIC OF PASSIVE COMPACT MOLTEN SALT REACTOR (PCMSR)

Andang Widi Harto
Jurusan Teknik Fisika, Fakultas Teknik, Universitas Gadjah Mada
Jl. Grafika 2. Yogyakarta – 55281
ABSTRACT
THE EFFECT OF FUEL VOLUME VARIATION TO THE BREEDING CHARACTERISTIC OF PASSIVE COMPACT MOLTEN SALT REACTOR (PCMSR). Passive Compact Molten Salt Reactor (PCMSR) is a nuclear reactor using molten salt fuel (UF4-ThF4-LiF) and graphite moderator. The using of U and Th fuel makes a possibility to design the reactor core that has breeding capability at a thermal neutron spectrum. The using of molten salt fuel makes a possibility to operate the reactor at high temperature at low pressure in order to increase the thermal efficiency and reduce possibility of accident due to overpressure. The breeding capability of PCMSR is depend on neutronics characteristics of its fuel assembly design. The neutronics characteristic of the fuel assembly is depend on the fuel volume fraction of the fuel assembly. The burn up and criticality calculation of this paper shows that the breeding capability of the PCMSR fuel assembly is achieved at the fuel volume fraction of 15%. Below this value, plutonium must be injected continually to maintain the reactor criticality. It means that the reactor has no breeding capability. At the fuel volume fraction more than 15%, the plutonium injection is needed only for the first 2.5 years of the PCMSR operation and at the next years, the PCMSR can maintain its criticality merely with Th-232 fuel input. At the fuel volume fraction higher than 15%, the reactor criticality increases with time due to the U-233 bulid up. It means that the breeding capability increases by increasing the fuel volume fraction.

Key words: PCMSR, breeding capability, fuel volume fraction
Published : Proceeding "SEMINAR NASIONAL PENGEMBANGAN ENERGI NUKLIR II 2009", Jakarta, 25 Juni 2009