Session: 03-02 Phase Change Thermal Storage

Paper Number: 108169

108169 - Expediting Heat Transfer in PCM Solidification With Optimized Fin Configuration 

Storing renewable energy sources such as solar and wind and utilizing them in spite of their intermittent availability is made possible by integrating Latent Heat Thermal Energy Storage Systems (LHTESS). These systems use high storage capabilities materials with isothermal behavior; Phase Change Materials (PCMs). They help to mitigate the imbalance caused in energy storage and its supply. The only bottleneck in their complete practical utilization is the low thermal conductivity of most PCMs, which significantly hinders the phase-changing phenomena. This investigation emphasized enhancing the heat transfer rate in the PCM solidification by employing optimized extended surfaces, i.e., longitudinal fins. A two-dimensional model for PCM solidification is numerically simulated using finite-volume method with fin numbers ranging from 4 to the maximum fin number, which can be accommodated on the HTF tube, i.e., 60 and HTF tube temperature from 265 K to 257 K. The obtained numerical results are present in a traditional method and by Response Surface Method (RSM). The latter method has been applied to optimize the fin numbers and the temperature of the Heat Transfer Fluid (HTF). In this regard, criteria of achieving a minimum liquid fraction along with a maximum heat transfer rate have been set for various combination cases of fin number and HTF tube temperature suggested by the RSM technique. Optimization of these two parameters is essential as they significantly affect the energy storage capacity, the fluidity, and the overall heat transfer rate in the liquid PCM. Numerical results demonstrated that employing an optimized fin configuration and the HTF temperature reported the maximum reduction in solidification. The effect of using more fins on the phase-changing phenomena is insignificant as more number of fins hinder the natural convection process and thus slow down the solidification rate. A best combination of 15 fin number and 257 K HTF tube is found to be favorable to expedite the heat transfer rate in the phase changing process. This impact is reduced when the fin number is increased beyond 15. In addition, a correlation is also developed for the liquid fraction accounting for different fin numbers and HTF temperatures.

Presenting Author: Amrita Sharma IIT Jodhpur

Presenting Author Biography: Amrita Sharma is currently pursuing her Ph.D. from the Mechanical Engineering Department at the Indian Institute of Technology Jodhpur, Rajasthan, India. Her research domain is to develop an efficient latent thermal energy storage system for low-temperature cooling applications.