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Published: 2025-06-26
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DOI: https://doi.org/10.53747/nst.v14i3.466
Issue
Vol. 14 No. 3 (2024)
Section
Articles
How to Cite
Duong Thanh, T., Tran, T. T. ., Tran, T. V. ., Hoang, T. H. ., Truong, H. T., Tran, C. T., Nguyen, T. T., & Kikura, H. . (2025). Fundamental investigation of natural convection induced by vertical heated rod using ultrasound velocity profiler. Nuclear Science and Technology, 14(3), 01-08. https://doi.org/10.53747/nst.v14i3.466

Fundamental investigation of natural convection induced by vertical heated rod using ultrasound velocity profiler

Tung Duong Thanh1, Thanh Tram Tran2, Tri Vien Tran2, Tan Hung Hoang3, Hoang Tuan Truong4, Chi Thanh Tran5, Tat Thang Nguyen6, Hiroshige Kikura7
1 s:3:"NTC";
2 Nuclear Training Center, Vietnam Atomic Energy Institute
3 Chungnam National university
4 Centre for Nuclear Technique
5 Vietnam Atomic Energy Institute
6 Posts and Telecommunications Institute of Technology
7 Laboratory for Zero-Carbon Energy, Institute of Innovation Research, Tokyo Institute of Technology, Japan

Main Article Content

Abstract

Natural convection is a fundamental phenomenon observed in various industrial, nuclear energy, power generation, and electronics cooling applications. In nuclear reactors, natural convection plays a crucial role in residual decay heat removal following reactor shutdown incidents or accidents. The design of fuel elements and fuel assemblies significantly influences flow rates, impacting natural circulation. Understanding natural convection requires analysis of the spatiotemporal velocity profile, which provides valuable insights into flow behavior. Therefore, the Ultrasonic Velocity Profiler (UVP) emerges as a suitable tool for observing natural convection flow behavior. However, since sound velocity in a fluid is temperature-dependent, it might affect the accuracy of velocity measurements. Hence, confirming the applicability of UVP becomes essential. In this study, a vertical heated rod with a diameter of 12 mm and a length of 225 mm is immersed at the center of a vertical acrylic pipe with a diameter of 144 mm and a height of 500 mm. The ultrasonic transducer is positioned outside the pipe to enable long-term flow behavior measurement. Utilizing the UVP technique, one-dimensional velocity profile behavior inside the pipe is measured and validated using Particle Image Velocimetry (PIV). Consequently, the spatiotemporal velocity profile is depicted in color scale to comprehend the natural flow behavior induced by a single heater rod.

Article Details

Keywords

Natural convection flow, UVP, PIV, heated rod

References

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