Heat transfer characteristics of a molten-salt thermal energy storage unit with and without heat transfer enhancement

Viscosity analysis of alkali metal carbonate molten salts at high temperature

“…5),6) Among these, LHS has been suggested as the most effective method in solar thermal energy applications because it exhibits small temperature fluctuations during heat storage and retrieval processes. 6),10), 11) Among several phase change materials, alkali metal molten salts are the most promising candidates for use as thermal storage media and heat transfer fluids in solar thermal energy systems. In particular, at high temperature, these materials can improve the energy conversion efficiency and reduce the cost of electricity production.…”

Molten salt composition and composites for improved latent heat thermal energy storage

“…This is clear in the research conducted in this field as there is very little consistency between the methods used to derive these values. Variations constantly occur in the results of the same properties of materials which in theory should be almost identical taking into consider the variations in the purity of the materials used [3,7,9,14]. Bauera [8] and his team found a ±7% and ±15% variation in data for heat capacity, and thermal diffusivity and conductivity of solar salt respectively compared to previously calculated values revealing inconsistency with tested results.…”

“…This property plays a sizeable role in efficiency; directly effecting heat exchange rates during charge and discharge process and melting point. Thus, techniques to alter this property could yield very beneficial results [9,12,13].…”

“…The efficiency of the molten salt LHTES is characterised by a range of thermo-physical properties most importantly thermal stability, heat capacity, thermal conductivity and melting point, these properties directly effecting heat storage capacity and transfer rates [8]. Standard solar salts exhibit low thermal conductivity, therefore altering the material's thermo-physical properties to increase this, may prove to be very beneficial for various commercial applications including CSP technology [9]. Utilising composite materials such as a NaNO3-KNO3-EG (Expanded Graphite) mixture has shown an increase in thermal conductivity compared to the pure nitrate by about 10-20% and 30-40% for a 5wt% and 10% addition of EG respectively [10].…”

Structural Analysis of Molten NaNO3by Molecular Dynamics Simulation

“…NaNO 3 is a well-known component of explosives. Recently, the molten state of NaNO 3 has also been used for fabricating heat-storage materials for application in solar power generation [1][2][3][4][5]. Adya et al for the first time investigated the microscopic atomic configuration and diffusion in molten NaNO 3 by means of X-ray diffraction measurement and molecular dynamics (MD) simulation, and compared its partial structure factors and partial pair distribution functions with those of molten NaNO 2 and the eutectic mixture of the NaNO 3 -NaNO 2 system showed good additivity for the intermolecular structure because the ionic radius of NO 3 and NO 2 ions are similar owing to the presence of a lone pair on the nitrite ion [6].…”