Design optimization of a novel annular fin on a latent heat storage device for building heating

The poor heat transfer performance of the heat exchanger leads to low heat storage efficiency of the latent heat storage device. To improve the heat transfer performance of the heat exchanger, a novel annular fin with inclined angle is proposed to enhance heat transfer of the heat exchanger. 12 fins with different structural parameters are designed and welded to the inner tube wall of the heat exchanger. The simulation model is in good agreement with the literature and the model is considered to be reliable. Based on the enthalpy-porosity model, the liquid fraction, temperature distribution, melting front, energy storage density and heat storage rate were used to compare and optimize the structural parameters of the annular fins. Results demonstrated that the difference in complete melting time due to the number of fins, fin arrangement, fin length and fin angle were 43 min, 85 min, 17 min and 10 min, respectively. The fin arrangement was the most significant in reducing the heat storage time. Compared to N = 4 and uniformly distributed fins, non-uniformly distributed fins reduced the total melting time of stearic acid by 53.13 % and 20.54 %. To be conclusive, the addition of non-uniformly distributed annular fins with 70 degrees inclination enhanced the heat transfer in the heat exchanger and saved a significant amount of heat storage time.

Automated summary

Improving the heat transfer performance of the heat exchanger can enhance the heat storage efficiency of the latent heat storage device. A novel annular fin with inclined angle is designed and welded to the inner tube wall of the heat exchanger to enhance heat transfer. Simulation results show that non-uniformly distributed fins reduced the total melting time of stearic acid by 53.13% and 20.54%, indicating that the addition of non-uniformly distributed annular fins with 70 degrees inclination improved heat transfer and reduced heat storage time significantly.