Indonesian Journal of Physics

Simulation of Three Points Bending SS316 to Know Mechanical Stress with ABAQUS

2025-06-28T08:24:06+00:00

The operating life of the Gen IV nuclear reactor, which is 60 years, will require material upgrades over a very long period of time. Stability, high reliability, adequate resources, and easy fabrication, as well as weldability, environmental impact, and aging, are other important aspects to consider during the material selection process. SS316 is currently in demand as a structural material for future Gen IV nuclear power plants operating at high temperatures. Although grade SS316 has been studied for current nuclear service conditions and other conventional applications, better data and models for long-term high-temperature properties are needed, especially with regard to primary to tertiary creep strain and creep-fatigue response. The three-point bending test on SS316 material can be modeled with ABAQUS simulation. The purpose of this study is to compare the distribution of the voltage profile for parameters at room temperature (25°C) and high temperature (650°C). In addition, simulations were conducted to compare the effects of load displacement (U2) variations, namely 25, 20 and 15 for each temperature. ABAQUS is an engineering simulation program based on finite element methods that can solve simple linear analysis problems to complex nonlinear simulations. ABAQUS comes with a comprehensive database of elements that can model almost any geometry. This simulation can describe the voltage profile that is spread over the geometry after the required parameters are entered. From the results obtained, the greater the displacement of U2, the smaller the maximum stress that can be resisted by the material. It also shows that at higher temperatures (650°C), materials tend to experience a decrease in strength or maximum stress compared to lower temperatures (25°C). So the material under test experiences a decrease in maximum strength or stress as the temperature increases and the U2 displacement.

Burn-up Analysis of TRIGA MARK II Research Reactor Fuel Elements Using OpenMC Program

2025-06-28T08:24:07+00:00

The TRIGA 2000 Bandung research reactor, a TRIGA MARK II type that has been operating critically since 1946, has experienced a significant decrease in criticality. This prompted researchers to implement a reshuffling scheme of 111 fuel elements to optimize burn-up throughout the reactor core area. Burn-up analysis of the TRIGA 2000 Bandung fuel elements has been carried out. This analysis aims to determine the burn-up capability and isotope production of each individual fuel element. The calculation uses the Monte Carlo-based OpenMC code that has gone through the verification and validation (V&V) stage based on the results of the MCNP simulation at 60% control rod withdrawal. Furthermore, the reactor power is varied by 100kW-500kW to see the reactor's ability to maintain criticality (k-eff) and obtain very small excess reactivity (ρ). The calculation of k-eff and ρ for 1 year (12 months) is applied in 2 ways, namely 5 hours per week and real-time. The results of real-time operations can optimize burn-up to near the critical point. The greater the power, the greater the number of neutrons for fission, thus accelerating the consumption of fissile material. The power of 200 kW was chosen for further analysis because at the end of the burn-up, the k-eff and ρ values approached the critical point. The results of the percentage of U-235 and U-238 burn-up to be greater in the middle area of the reactor core (ring B) and consistently decreased towards the edge of the reactor core (ring G). As a result, the mass production of Pu-239 was also very high in the ring B area. This also happened to toxic isotopes such as Sm-149, Xe-133, Xe-135 which tended to be high in that area. The high burn-up rate and isotope production became a reference for future research to apply the reshuffling concept to the TRIGA 2000 Bandung reactor core

Material Challenges for Corrosive Environments and High Temperatures in Lead-Cooled Fast Reactor

2025-06-28T08:24:07+00:00

Research on one of the generation IV reactors, the Lead-Cooled Fast Reactor (LFR), began in the 1950s. The development of this reactor continues until now. However, there are material challenges in the development of LFR. LFR coolant that uses liquid Pb or Pb-Bi is one of the challenges in this reactor because it causes severe corrosion. Researchers have tested various materials such as steel, ceramics, composites, and refractory alloys in liquid Pb or Pb-Bi environments to assess their corrosion resistance. These materials have shown improved radiation performance at high temperatures and have been developed (such as ODS, FeCrAl, SS316, AISI 316 EP823, AISI 304, and HCM12A). However, these materials are not yet sufficiently compatible with corrosion performance. The results indicate that no metal or ceramic material currently proves to be completely resistant to corrosion and radiation over the long term. The LFR system is intriguing but has limited applicability until suitable construction material designs are further identified.

Influence of Concentration of Graphene Oxide to Thermal Diffusivity in Nano-liquid Form Using Thermal Lens Method

2025-06-28T08:24:07+00:00

This study examines the effect of graphene oxide (GO) concentration on thermal diffusivity in nano-liquid formulations using the thermal lens method. Nano-liquid samples with varied GO concentrations were prepared and analyzed. Results indicate an increase in thermal diffusivity with rising GO concentration up to a threshold, beyond which further increments yield diminishing returns. This behavior is attributed to the unique thermal transport mechanisms enabled by GO nanosheets. These findings offer insights for optimizing GO-based nano-liquids for thermal management applications. Moreover, the study underscores the efficacy of the thermal lens method for probing thermal properties in nanofluid systems.

Evaluation of radioactive contamination of radon gas inside and outside the building of the College of Education - Iraqi University – Iraq

2025-06-28T08:24:08+00:00

Radon gas is a major indoor air pollutant, is found inside and outside buildings, and is the main cause of lung cancer. Therefore, determining its concentration levels and the dose resulting from inhalation of this gas is important for the public health of people inside buildings.

The aim of the research includes measuring radon gas concentrations in the air inside and outside the building of the College of Education at Iraqi University using a nuclear trace detector (CR-39). The detector (1x2) cm² was exposed for a full month during the winter because this period roughly represents the official working hours at the college. It is clear from the results of the study that the concentrations of radon gas inside buildings are higher than their concentrations outside buildings, and this increase in concentration is due to the fact that the walls of buildings are the main source of radon generation inside buildings, as it was shown that building materials have played an important role in increasing the concentrations of radon gas inside buildings in addition to the age of the buildings and the height above ground level.

The annual equivalent dose values for exposure to radioactive radon gas and its effect on the lungs ranged between 0.43 and 1.34 mSv/y and an average of 0.86 mSv/y. These values are the lowest allowed by ICRP (3-10) mSv/y.