Investigation of Natural Circulation Flow Under Steady-State Conditions Using a Rectangular Loop

Authors

  • Iwan Roswandi Research Centre for Nuclear Reactor Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency, Building No. 80 BJ Habibie Science and Technology Area, South Tangerang 15314, Indonesia
  • Dimas Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Jakarta, Kampus A UNJ Gedung L, Jl. Rawamangun Muka Raya, Kec. Pulo Gadung, Kota Jakarta Timur, DKI Jakarta 13220, Indonesia
  • Hyundianto Arif Gunawan Research Centre for Nuclear Reactor Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency, Building No. 80 BJ Habibie Science and Technology Area, South Tangerang 15314, Indonesia
  • Arif Adtyas Budiman Research Centre for Nuclear Reactor Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency, Building No. 80 BJ Habibie Science and Technology Area, South Tangerang 15314, Indonesia
  • Almira Citra Amelia Research Centre for Nuclear Reactor Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency, Building No. 80 BJ Habibie Science and Technology Area, South Tangerang 15314, Indonesia
  • Sanda Research Centre for Nuclear Reactor Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency, Building No. 80 BJ Habibie Science and Technology Area, South Tangerang 15314, Indonesia
  • Hendro Tjahjono Research Centre for Nuclear Reactor Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency, Building No. 80 BJ Habibie Science and Technology Area, South Tangerang 15314, Indonesia
  • Mulya Juarsa Research Centre for Nuclear Reactor Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency, Building No. 80 BJ Habibie Science and Technology Area, South Tangerang 15314, Indonesia

Keywords:

NPP, Grashof Number, FASSIP-05, NCL, Passive cooling

Abstract

Passive safety systems, particularly during active system failures, have become a significant concern. Understanding natural circulation phenomena is crucial for developing passive cooling systems in nuclear power plants. With its significant findings, this study examines the flow patterns under steady-state conditions and assesses the Grashof number. The experimental approach involved maintaining temperature differences of 60 °C, 70 °C, 80 °C, and 90 °C for 3 hours, with three replications. The temperature alterations impact water's physical properties, such as density, viscosity, and specific heat. The calculations reveal that the minimum Grashof number that occurs at 60 °C is 2.49×10¹², while the maximum observed at 90 °C is 9.42×10¹², with an R² value of 0.96533. The observation of turbulent flow patterns during each temperature fluctuation, which aligns with previous research on the Ress value of Grm/NG, has significant implications for the design and operation of passive safety systems in nuclear power plants.

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Published

2026-03-05

How to Cite

Roswandi, I., Dimas, Gunawan, H. A., Budiman, A. A., Amelia, A. C., Sanda, … Juarsa, M. (2026). Investigation of Natural Circulation Flow Under Steady-State Conditions Using a Rectangular Loop. Jurnal Teknologi Reaktor Nuklir Tri Dasa Mega, 26(2), 77–86. Retrieved from https://ejournal.brin.go.id/tridam/article/view/15523

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