PCM		phase change material
HTPCM		high-temperature phase-change material
TES		thermal energy storage
CSP		concentrating solar power plant
HTF		heat-transfer fluid
EMB		energy-mass balance
FDM		finite difference method
RHBIM		refined heat balance integral method
RPD		relative percent difference
${\lambda }_{\ell }$	$\mathrm{W}/\mathrm{m}\mathrm{K}$	Thermal conductivity of the liquid
${\lambda }_s$	$\mathrm{W}/\mathrm{m}\mathrm{K}$	Thermal conductivity of the solid
${\alpha }_{\ell }$	$1/\mathrm{K}$	Thermal expansion coefficient of the liquid
${\alpha }_s$	$1/\mathrm{K}$	Thermal expansion coefficient of the solid
$C_{\ell }$	$\mathrm{kJ}/\mathrm{kg}\mathrm{K}$	Specific heat capacity of the liquid
$C_s$	$\mathrm{kJ}/\mathrm{kg}\mathrm{K}$	Specific heat capacity of the solid
$B_{\ell }$	$\mathrm{Pa}$	Bulk modulus of the liquid
$B_s$	$\mathrm{Pa}$	Bulk modulus of the solid
$K_{\ell }$	$1/\mathrm{Pa}$	Compressibility of the liquid
$K_s$	$1/\mathrm{Pa}$	Compressibility of the solid
${\rho }_{\ell }\left(t\right)$	$\mathrm{kg}/{\mathrm{m}}^3$	Time dependent liquid density
${\rho }_s\left(t\right)$	$\mathrm{kg}/{\mathrm{m}}^3$	Time dependent solid density
${\rho }_{\ell }^{*}$	$\mathrm{kg}/{\mathrm{m}}^3$	Density of the liquid in the isochoric limit
$P^{*}$	$\mathrm{MPa}$	Inner pressure in the isochoric limit
$T_f^{*}$	$\mathrm{K}$	Fusion temperature in the isochoric limit
$L_f^{*}$	$\mathrm{kJ}/\mathrm{kg}$	Latent heat of fusion in the isochoric limit
$T_f\left(t\right)$	$\mathrm{K}$	Time dependent fusion temperature
$L_f\left(t\right)$	$\mathrm{kJ}/\mathrm{kg}$	Time dependent latent heat of fusion
$R\left(t\right)$	$\mathrm{m}$	Time dependent PCM radius
$\overline{r}\left(t\right)$	$\mathrm{m}$	Time dependent radius of the solid phase
$T_{\mathbb{H}}$	$\mathrm{K}$	Temperature at the surface of the PCM
${\tilde{k}}_s$	$\mathrm{Pa}$	Elastic constant of the spring
$\Delta U$	$\mathrm{J}$	Internal energy change
$\Delta V$	${\mathrm{m}}^3$	Total volume change
$\Delta Q_f$	$\mathrm{J}$	Energy absorbed as latent heat
$\Delta Q$	$\mathrm{J}$	Thermal energy absorbed
$M_{\mathrm{PCM}}$	$\mathrm{mg}$	Total mass of the PCM
$\Delta M_s$	$\mathrm{mg}$	Mass of melted solid
$t_{\max }$	s	Duration of the melting process