Thermal storage systems have to move heat in and out efficiently and repeatedly. Storage media such as phase change materials, thermal oil, molten salt and water often have low thermal conductivity, so the heat exchanger becomes the limiting component for charge and discharge power.
What storage duty demands
- A large heat transfer surface to compensate for low conductivity on the storage side
- Stable outlet temperature during discharge
- Structural tolerance of repeated expansion and contraction
- Materials compatible with corrosive storage media
Why finned tubes fit
Fins extend the surface inside a limited volume while keeping the pressure drop on the storage side under control. The bundle can be arranged as an immersed bank, a coil or an integrated tank element. Fin spacing and row depth are selected against the storage medium, the required charge and discharge time and the allowable temperature difference.
Typical arrangements
Common solutions include immersed finned tube banks in storage tanks, finned coils for phase change materials, and bundles integrated with heat pumps or Carnot battery systems. Thermal stress, support structure and material compatibility have to be considered together with the thermal calculation.
Wuxi Mazelu designs finned tube bundles against the storage medium and charge / discharge duty. Send the storage capacity, power and allowed time for a first assessment.