The present research focused on investigating the effects of ultrasonic field on the solidification process of PCM in a latent heat storage unit under varying frequency ( = 28 kHz and 40 kHz), power ( = 30 W, 39 W, and 48 W), heat transfer fluid inlet temperature ( = 10 °C, 20 °C, and 30 °C) and heat transfer flowrate ( = 5 L/min, 6 L/min, and 7 L/min) values. A rectangular stainless-steel cavity with dimensions of 100 mm × 100 mm × 300 mm was used as a latent heat thermal energy storage (LHTES) unit. Temperature measurements were carried out using 16 T-type thermocouples over a 14-hour test period. Mass-averaged temperature (), liquid fraction (), and discharged energy () values were computed, and the results were comparatively discussed for cases with and without ultrasonic field implementation. The findings demonstrated that the ultrasonic field negatively impacted the solidification process of PCM. In the absence of the ultrasonic field, i.e., reference case, 372.9 kJ of thermal energy was discharged. However, when = 28 kHz with = 48 W was applied, the energy release decreased to 281.9 kJ, corresponding to 24.40 %. Similarly, at a higher frequency ( = 40 kHz) with the same (48 W), the thermal energy release further decreased to 204.2 kJ (45.24 %). Additionally, it was observed that increasing the had a negative effect on the solidification process similar to that increasing the frequency. Lastly, was found to be the least effective parameter. In conclusion, this study revealed that the application of an ultrasonic field adversely affects the solidification behavior of PCM, leading to a reduction in the amount of energy discharged during the process.
