Analisis Subkanal pada Fuel Assembly Reaktor KLT-40S untuk Menghitung Distribusi Karakteristik Termohidrolik Menggunakan RELAP5-3D©
AGUNG KRISNA MUKTI, Dr. Ir. Alexander Agung, S.T., M.Sc.; Dr. Ing. Ir. Sihana
2022 | Skripsi | S1 TEKNIK NUKLIRPenelitian ini melakukan perhitungan simulasi besaran termohidrolika dari perangkat bahan bakar reaktor KLT-40S. Penelitian dilakukan untuk mendapatkan data tentang perangkat bahan bakar. Penelitian sejenis telah dilakukan sebelumnya, tetapi untuk mendapatkan data tentang teras reaktor. Penelitian dilakukan dengan memodelkan perangkat bahan bakar yg tersusun dari 84 sub kanal. Perhitungan dilakukan terhadap setiap sub kanal dengan simulasi menggunakan paket program RELAP5-3D berdasarkan model yang dikembangkan. Simulasi dilakukan untuk tingkat daya normal (150 MW), divariasikan (50%, 90%, 105% dan 110%) dari normal, laju aliran massa normal (761 kg/s), divariasikan (50%, 90%, 105% dan 110%) dari normal dan ketika terjadi gerakan rolling (15°, 30°, 45°) atau pitching (5° dan 10°). Hasil simulasi menunjukkan distribusi temperatur bahan bakar; temperatur, tekanan, laju aliran massa, kecepatan aliran pendingin dan MDNBR dari perangkat bahan bakar reaktor KLT-40S. Kesimpulan dari penelitian ini adalah pengaruh akibat perubahan daya dan laju aliran massa saling berkebalikan. Meningkatnya daya menyebabkan meningkatnya temperatur bahan bakar dan pendingin serta menurunnya nilai MDNBR. Gerakan rolling tidak memberikan perubahan yang signifikan terhadap parameter termal hidraulik perangkat bahan bakar. Semakin besar percepatan akibat gerakan pitching maka temperatur dan tekanan pendingin akan semakin rendah serta MDNBR akan semakin tinggi. Model perangkat bahan bakar yang dikembangkan bisa memenuhi kriteria keselamatan berdasarkan nilai MDNBR dan temperatur bahan bakar.
This study performs simulation calculations of thermohydraulic quantities from the KLT-40S fuel assembly. The research was conducted to obtain data about the fuel assembly. Similar studies have been carried out previously, but to obtain data on the reactor core. The research was conducted by modeling the fuel assembly which is divided to 84 sub-channels. Calculations were made for each sub-channel by simulation using the RELAP5-3D program package based on the developed model. Simulations were carried out for normal power level (150 MW), varied (50%, 90%, 105% and 110%) from normal, normal mass flow rate (761 kg/s), varied (50%, 90%, 105% and 110%) of normal and when rolling (15°, 30°, 45°) or pitching (5° and 10°) motion occurs. The simulation results show the distribution of fuel temperature; temperature, pressure, mass flow rate, flow velocity of the coolant and MDNBR of the KLT-40S fuel assembly. The conclusion of this study is that the effect of changes in power and mass flow rate is inversely related. The increase in power causes an increase in the temperature of the fuel and coolant as well as a decrease in the MDNBR value. The rolling motion does not provide a significant change to the hydraulic thermal parameters of the fuel device. The greater the acceleration due to the pitching motion, the lower the coolant temperature and pressure also the higher the MDNBR. The fuel assembly model can meet the safety criteria based on the MDNBR value and fuel temperature.
Kata Kunci : RELAP5-3D, KLT-40S, MDNBR, analisis subkanal