ABSTRACT
The application of a phase change material (PCM) as thermal energy storage observed unprecedented growth due to its large latent heat storage capacity at a constant temperature. However, the design of an energy storage heat exchanger is a challenging task because of the poor thermal conductivity of PCMs. In an effort to improve the heat exchanger design, this paper presents a numerical performance investigation of a PCM-based multitube heat exchanger incorporated with two new fin configurations. The analysis of the results shows that the placement of fins is one of the important aspects, which needs to be cogitated in the design of heat exchangers.
Nomenclature
Amush | = | mushy zone constant (kg/m3 · s) |
L | = | latent heat fusion (J/kg) |
cp | = | specific heat of PCM (J/kg · K) |
Nu | = | Nusselt number, = hl/k |
= | external body forces (N) | |
p | = | static pressure (N/m2) |
g | = | gravity acceleration (m/s2) |
Si | = | momentum source term (Pa/m) |
h | = | sensible enthalpy (J/kg) |
T | = | temperature (°C or K) |
H | = | enthalpy (J/kg) |
= | velocity component (m/s) | |
K | = | thermal conductivity (W/m · K) |
= | pull velocity (m/s) | |
Greek letters | = | |
β | = | thermal expansion coefficient (K) |
ρ | = | fluid density (kg/m3) |
γ | = | liquid fraction |
= | stress tensor (N/m2) | |
µ | = | dynamic viscosity (kg/m · s) |
Subscripts | = | |
HTF | = | heat transfer fluid |
Ref | = | reference |
ini | = | initial |
s | = | solidus of the phase change material |
l | = | liquidus of the phase change material |
Nomenclature
Amush | = | mushy zone constant (kg/m3 · s) |
L | = | latent heat fusion (J/kg) |
cp | = | specific heat of PCM (J/kg · K) |
Nu | = | Nusselt number, = hl/k |
= | external body forces (N) | |
p | = | static pressure (N/m2) |
g | = | gravity acceleration (m/s2) |
Si | = | momentum source term (Pa/m) |
h | = | sensible enthalpy (J/kg) |
T | = | temperature (°C or K) |
H | = | enthalpy (J/kg) |
= | velocity component (m/s) | |
K | = | thermal conductivity (W/m · K) |
= | pull velocity (m/s) | |
Greek letters | = | |
β | = | thermal expansion coefficient (K) |
ρ | = | fluid density (kg/m3) |
γ | = | liquid fraction |
= | stress tensor (N/m2) | |
µ | = | dynamic viscosity (kg/m · s) |
Subscripts | = | |
HTF | = | heat transfer fluid |
Ref | = | reference |
ini | = | initial |
s | = | solidus of the phase change material |
l | = | liquidus of the phase change material |