Convective boiling

Accurate prediction of heat transfer in two-phase convective flow conditions is crucial for the safety, reliability and efficiency of various thermodynamic systems. A particularly interesting and complex way of heat transfer is boiling, which can significantly improve the cooling capacity of hot surfaces. An in-depth understanding of the mechanisms of fermentation is very important and represents the core of research in the THELMA laboratory.

The main experimental device is a test section for measuring heat flux in annular geometry, reminiscent of the geometry of the immediate vicinity of the fuel rod in light-water nuclear reactors - see figure. The test section is designed to allow visual observation of different boiling regimes with a high-speed camera (see video), simultaneous measurement of heat flux and control of surface temperature with heating water. This enables operation even in the immediate vicinity of the boiling crisis or. critical heat flux.

Posts:

• ZAJEC, Bostjan, Koncar, Bostjan, MATKOVIC, Marko, CIZELJ, Leon. Experimental investigation of subcooled flow boilingof R245fain a narrow horizontal annular duct, Proceedings of the 5th World Congress onMomentum, Heat and Mass Transfer (MHMT'20). DOI: 10.11159 / icmfht20.170
• ZAJEC, Boštjan, BASAVARAJ, Anil Kumar, MIKUŽ, Blaž, KONÄŒAR, Boštjan, SHARMA, Mohit Pramod, MATKOVIÄŒ, Marko. Experimental and Numerical Analysis of Heat Transfer on the Annular Test Section. 29th International Conference Nuclear Energy for New Europe, Portorož, Slovenia, 2020 September 7-10. Conference proceedings.
• ZAJEC, Bostjan, MATKOVIC, Marko, CIZELJ, Leon. Heat transfer measurements in a single-phase flow of refrigerant R245fa in annular geometry. 28th International Conference Nuclear Energy for New Europe, Portorož, Slovenia, 2019 September 9-12. Conference proceedings.
• BASAVARAJ, Anil Kumar, MIKUŽ, Blaž, MATKOVIÄŒ, Marko. Flow and heat transfer CFD analysis in the section of THELMA for wall surface temperature determination. 28th International Conference Nuclear Energy for New Europe, Portorož, Slovenia, 2019 September 9-12. Conference proceedings.
• BASAVARAJ, Anil Kumar, ZAJEC, Bostjan, MATKOVIC, Marko. Accurate measurements of the local heat transfer coefficients along the dedicated test section. 27th International Conference Nuclear Energy for New Europe, Portorož, Slovenia, 2018 September 10-13. Conference proceedings.
• ZAJEC, Bostjan, CIZELJ, Leon, MATKOVIC, Marko. Production of a test section for critical heat flow measurements under isothermal boundary conditions. Conference of Young Nuclear Experts: Abstracts of Papers Presented at the Conference at the Reactor Center Podgorica, February 26, 2018. 1st ed. Ljubljana: Association of Nuclear Experts of Slovenia. 2018, p. 26.
• MATKOVIÄŒ, Marko, CIZELJ, Leon, KLJENAK, Ivo, KONÄŒAR, Boštjan, MIKUŽ, Blaž, SUŠNIK, Andrej, TISELJ, Iztok, ZAJEC, Boštjan. Building a unique test section for local critical heat flux studies in light water reactor: like accident conditions. HEFAT2017, 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portorož, Slovenia, 2017 July 17-19.
• MATKOVIC, Marko, CIZELJ, Leon, KLJENAK, Ivo, KONÄŒAR, Boštjan, LESKOVAR, Matjaž, PROŠEK, Andrej, TISELJ, Iztok. Designing an advanced experimental test apparatus for conjugate heat transfer studies. SWINTH-16, Specialists Workshop on Advanced Instrumentation and Measurement Techniques for Nuclear Reactor Thermal Hydraulics, Livorno, 2016 June 15-17.

Edited by: Anil Kumar Basavaraj