DSpace Collection:http://hdl.handle.net/10174/52712026-04-08T03:57:22Z2026-04-08T03:57:22ZThermal conductivity of concrete at high temperatures for thermal energy storage applications: Experimental analysisLucio-Martin, T.Roig-Flores, M.Izquierdo, M.Alonso, M.C.http://hdl.handle.net/10174/301182021-09-07T14:33:25Z2020-12-25T00:00:00ZTitle: Thermal conductivity of concrete at high temperatures for thermal energy storage applications: Experimental analysis
Authors: Lucio-Martin, T.; Roig-Flores, M.; Izquierdo, M.; Alonso, M.C.
Abstract: Thermal conductivity plays an important role in energy storage when the materials are charging and discharging.
This paper presents an experimental investigation of the evolution of thermal conductivity up to 600 ◦C in
different concretes. Moreover, the thermal conductivity was measured during thermal fatigue cycles when
temperature ranged between 300 and 600 ◦C, simulating the operation conditions in a storage system of molten
salts in a Concentrating Solar Power Plant (CSP). Five concrete compositions were analysed using diverse types of
aggregates with different thermal response, covering a wide range of the initial thermal conductivity. The results
confirm that the loss of thermal conductivity with temperature during the first heating is mainly due to the free
water loss. Moreover, the type of aggregate influences the overall thermal performance of concrete due to its
thermal conductivity and the volumetric differences with the cement paste. Siliceous aggregates underwent the
highest decrease of thermal conductivity of concrete (+50%) with regard to room temperature. Regarding the
cooling phase, thermal conductivity recovers between 20% and 40% depending on the type of aggregate. The
outcomes of the present study demonstrate that the assumption of a constant thermal conductivity value in
numerical simulations to predict its thermal capacity for energy storage is not appropriate.2020-12-25T00:00:00Z