TY  - EJOU
AU  - Idrissi, Abdellah 
AU  - Abddaim, Elbachir 
AU  - Mghari, Hicham El 
AU  - Amraoui, Rachid El 
AU  - Sakami, Siham 
AU  - Boukhattem, Lahcen 
AU  - Addou, Brahim 

TI  - Transient Thermo-Hydraulic Behavior of a Thermocline Thermal Energy Storage Tank: A CFD Investigation
T2  - Energy Engineering

PY  - 
VL  - 
IS  - 
SN  - 1546-0118

AB  - This study numerically investigates the influence of inlet–outlet arrangement on the thermo-hydraulic performance of a thermocline thermal energy storage (TES) tank using three-dimensional transient CFD simulations in ANSYS Fluent. Four different inlet–outlet configurations were analyzed under identical discharge conditions to evaluate their effects on thermal stratification, discharge efficiency, and internal flow behavior. The numerical model was developed using the continuity, momentum, and energy equations with the Boussinesq approximation and validated against reference experimental data with deviations below 5%. The results showed that the inlet–outlet arrangement significantly affects thermocline evolution and thermal mixing inside the storage tank. Among the investigated configurations, Configuration 2 exhibited the most favorable thermo-hydraulic behavior, improving thermal stratification and discharge efficiency by approximately 18%–22% compared with the baseline configuration because of reduced recirculation intensity and weaker thermal mixing. Although Configuration 2 produced a moderate increase in pressure drop and pumping power, the improved thermal performance justified the associated hydraulic penalty. The obtained findings indicate that relatively simple modifications in inlet–outlet positioning can improve thermocline preservation and thermal energy recovery in compact TES systems.
KW  - Thermal energy storage; thermocline tank; thermal stratification; CFD; inlet–outlet arrangement; discharge efficiency

DO  - 10.32604/ee.2026.083896