Experimental investigation of the LHS system and comparison of the stratification performance with the SHS system using CFD simulation

Abstract Stratified storage tanks are vital for the effective storage and retrieval of energy intended for various solar thermal applications. An experimental investigation is carried out to study the stratification behavior during the charging process, in a packed bed thermal storage unit filled with Phase Change Materials (PCMs) encapsulated spherical capsules. The configuration used in the experimental investigation is modeled, and the stratification behavior is analyzed using the commercially available Computational Fluid Dynamics (CFDs) software FLUENT, and the results are validated using the experimental analysis. The CFD analysis is also performed for a sensible heat storage tank of similar geometrical dimensions. In the CFD analysis, apparent heat capacity method is used to model the phase change phenomenon during the melting process in PCM. The enhancement in the stratification performance in Latent Heat Storage (LHS) system, that considerably increases the charging efficiency, is observed from the present investigation.

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