TY - JOUR

T1 - Thermal conductivity measurement of thermochemical storage materials

AU - Fopah Lele, Armand

AU - N'Tsoukpoe, Kokouvi Edem

AU - Osterland, Thomas

AU - Kuznik, Frédéric

AU - Ruck, Wolfgang

PY - 2015/10/5

Y1 - 2015/10/5

N2 - Abstract Thermal properties related to heat and mass transfer are crucial when designing thermochemical heat storage systems. Therefore, enhancing this phenomenon lies in the thermal conductivity of the used material. The effective thermal conductivity of salt hydrates and host matrices is measured using two different methods by differential scanning calorimeter from 100 to 200 °C and radial flow apparatus called guarded hot cartridge from 20 to 70 °C, where the method effect is less than 12%. On this latter, the results as function of temperature was modelled and theoretical correlation of effective thermal conductivity of the material bed presented. Four inorganic salts often used in thermochemical energy storage (CaCl2, MgCl2, SrBr2 and MgSO4) and host matrices (activated carbon, expanded natural graphite and silica gel) were used as samples and the results on both systems for only salts give a thermal conductivity in the range of 0.3-1.3 W m-1 K-1 with measurement uncertainty less than 14%. These obtained data are satisfactory with literature values. Regarding the results, the need of composite design is mandatory to achieve great thermal performances in thermal storage systems, especially in closed systems. The presented results can be used for the evaluation and the improvement of heat and mass transfer in thermochemical and sorption heat storage systems.

AB - Abstract Thermal properties related to heat and mass transfer are crucial when designing thermochemical heat storage systems. Therefore, enhancing this phenomenon lies in the thermal conductivity of the used material. The effective thermal conductivity of salt hydrates and host matrices is measured using two different methods by differential scanning calorimeter from 100 to 200 °C and radial flow apparatus called guarded hot cartridge from 20 to 70 °C, where the method effect is less than 12%. On this latter, the results as function of temperature was modelled and theoretical correlation of effective thermal conductivity of the material bed presented. Four inorganic salts often used in thermochemical energy storage (CaCl2, MgCl2, SrBr2 and MgSO4) and host matrices (activated carbon, expanded natural graphite and silica gel) were used as samples and the results on both systems for only salts give a thermal conductivity in the range of 0.3-1.3 W m-1 K-1 with measurement uncertainty less than 14%. These obtained data are satisfactory with literature values. Regarding the results, the need of composite design is mandatory to achieve great thermal performances in thermal storage systems, especially in closed systems. The presented results can be used for the evaluation and the improvement of heat and mass transfer in thermochemical and sorption heat storage systems.

KW - Energy research

KW - Thermal conductivity

KW - Salt hydrates

KW - energy storage

KW - Engineering

KW - Guarded heat cartridge

KW - DSC

UR - http://www.scopus.com/inward/record.url?scp=84937142748&partnerID=8YFLogxK

U2 - 10.1016/j.applthermaleng.2015.06.077

DO - 10.1016/j.applthermaleng.2015.06.077

M3 - Journal articles

VL - 89

SP - 916

EP - 926

JO - Applied Thermal Engineering

JF - Applied Thermal Engineering

SN - 1359-4311

M1 - 6771

ER -