Abstract
This paper presents the results of experimental and numerical research activities on a packed bed sensible thermal energy storage (TES) system. The TES consists of a cylindrical steel tank filled with small alumina beads and crossed by air used as the heat transfer fluid. Experimental tests were carried out while varying some operating parameters such as the mass flow rate, the inlet–outlet temperature thresholds and the aspect ratio (length over diameter). Numerical simulations were carried out using a one-dimensional model, specifically developed in the Matlab-Simulink environment and a 2D axisymmetric model based on the ANSYS-Fluent platform. Both models are based on a two-equation transient approach to calculate fluid and solid phase temperatures. Thermodynamic properties were considered to be temperature-dependent and, in the Computational Fluid Dynamics (CFD) model, variable porosity of the bed in the radial direction, thermal losses and the effective conductivity of the alumina beads were also considered. The simulation results of both models were compared to the experimental ones, showing good agreement. The one-dimensional model has the advantage of predicting the axial temperature distribution with a very low computational cost, but it does not allow calculation of the correct energy stored when the temperature distribution is strongly influenced by the wall. To overcome this problem a 2D CFD model was used in this work.
Highlights
Introductionthermal energy storage (TES) systems based on packed beds of rocks or other solid materials allow storage of thermal energy in the form of sensible heat at high temperature as required in many industrial applications
thermal energy storage (TES) systems based on packed beds of rocks or other solid materials allow storage of thermal energy in the form of sensible heat at high temperature as required in many industrial applications.In concentrating solar power plants (CSP), energy storage has a fundamental role for continuity of power generation and optimum dispatching management
The test facility consists of an open circuit with an insulated steel tank filled with alumina beads that is used as the storage media while hot air is employed as HTF
Summary
TES systems based on packed beds of rocks or other solid materials allow storage of thermal energy in the form of sensible heat at high temperature as required in many industrial applications. In concentrating solar power plants (CSP), energy storage has a fundamental role for continuity of power generation and optimum dispatching management. TES can be used in numerous commercial and industrial applications, often integrated with conventional energy sources such as advanced adiabatic compressed air energy storage systems (ACAES) [3], thermal-fluid systems [4], gas-cooled nuclear reactors [5], drying processes [6], catalytic reactors [7] and in residential buildings [8]. There are several methods for storing thermal energy through both physical and chemical processes [9]: sensible, latent and chemical storage.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
