MATHEMATICAL MODELLING OF TECHNOLOGICAL PROCESSES AND SYSTEMS

Development of numerical model for buoyancy-driven heat transfer between parallel plates

  • 1 University of Rijeka, Faculty of Engineering, Rijeka. Croatia
  • 2 University of Rijeka, Faculty of Maritime Studies, Croatia

Abstract

The main objective of this study is to develop and experimentally validate a finite volume numerical model for buoyancy-driven (natural convective) heat transfer between parallel plates representative of plate fin passive heat sinks. The validation employs a calorimetry-based setup: a vertical aluminum plate fin heat sink is mounted to the only uninsulated wall of an otherwise well-insulated, water-filled rectangular vessel that serves as a controllable heat source. The total heat transfer rate and convective heat transfer coefficients are inferred from the time evolution of the calorimetric water temperature, and fin surface temperatures are measured at several characteristic locations. The model resolves conjugate heat transfer between the solid heat sink and the surrounding air. Numerical predictions of heat transfer rate, fin surface temperatures, and convective heat transfer coefficients show good agreement with measurements and with established literature correlations, confirming the validity of the mathematical model and numerical procedure. The developed numerical model can be used for further analyses and optimization processes.

Keywords

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