A performance analysis of the spray-type packed bed thermal energy storage for concentrating solar power generation. (July 2022)

• Record Type: Journal Article
• Authors: Bai, Yakai; Wang, Liang; Lin, Lin; Lin, Xipeng; Peng, Long; Chen, Haisheng
• Is Part Of: Journal of energy storage. Volume 51(2022)
• Publication Date: 2022-07
• Subjects: Concentrated solar power -- Spray-type packed bed -- Thermal energy storage -- Liquid holdup; TES thermal energy storage -- HTC heat transfer coefficient -- HTF heat transfer fluid -- L flow rate, m3/s -- Mdesign designed mass of fluid charged into the packed bed -- Nu Nusselt number -- p pressure, MPa -- pr profile -- Pr Prandtl number -- r radial direction -- Re Reynolds number -- s specific entropy, J/kg/°C -- sat saturation -- Sim simulation -- t time, s -- T temperature, °C -- u velocity m/s -- V total volume of the packed bed, m3 -- z vertical direction -- out outlet -- l liquid phase -- M midpoint -- s solid phase -- sb standby -- st static -- side side wall -- top top wall -- W wall -- ρ density, kg/m3 -- σ gas–liquid interfacial tension -- φ porosity -- Φ ratio -- CSP concentrated solar power -- ZBS Zehner, Bauer and Schlünder Model; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2022.104187
• Languages: English
• ISSNs: 2352-152X

Abstract

Abstract: The concept of spray-type packed bed thermal energy storage (medium and high temperature thermal energy storage, from 200 °C to 350 °C, Alumina pellets+T66 fluid) has been proposed in our previous investigation. Its low-cost and high-efficiency shows its promising application prospect. Further investigation of the new concept is carried out both numerically and experimentally in this paper. First, the "charging-standby-discharging" cycle of a pilot spray-type packed bed is investigated experimentally. Second, the dynamic liquid holdup of the spray-type packed bed is correlated with the experiment data and is applied to build the mass balance equations. Based on the energy balance equations and mass balance equations, a three-phase one-dimensional transient model for the spray-type packed bed is established. Results from the experiment confirms the correctness of the numerical model. Based on the model, the liquid holdup of the packed bed during the "charging-standby-discharging" cycle is studied. At last, sensitivity analysis was carried out to study the influence of the parameters of the "charging-standby-discharging" process on the thermal performance of the spray-type packed bed. Values of these parameters can be found to achieve the best thermal performance of a spray-type packed bed.