Natural Convection Flow of Nano-encapsulated Phase Change Materials Water Suspension in a Square Enclosure with Dual Heated Circulars

Natural convection flow and transferring of heat from nano-encapsulated phase change materials (NEPCM) suspension in square enclosure is investigated numerically. The enclosure is thermally insulated on three sides and contains two internal circular obstacles that act as isothermal hot walls, while the remaining wall is kept cold. The particles of NEPCM possess core shelled structures having PCM as core and solid shell, thereby uniting PCMs latent heat storage capability with nanofluids’ enhanced convective performance. Main aim of this study involves the analysis of phase change mechanisms and the coupled heat transfer, and to evaluate thermal functioning for the NEPCM suspension under natural convection. Impact of vital dimensionless factors including Stefan number, PCM core’s non-dimensional fusion temperature, NEPCM volume fraction, and Rayleigh number are systematically examined for understanding their effect on heat transfer characteristics. Relevant equations are altered to non-dimensional forms and finite element method is used to solve them. Grid independence and validity tests are conducted for ensuring the numerical stability and accuracy. Results depict that NEPCM particles’ fusion temperature is crucial parameter influencing NEPCMs’ heat transfer increase in natural convection flow. In particular, increasing non-dimensional fusion temperature of NEPCM particles to ۳% directs towards significant ۳% enhancement of average Nusselt number at 𝑅𝑎 = . The outcomes exhibit NEPCMs’ potential to substantially increase thermal efficacy, which provides unprecedented enhancement compared to the previously reported studies.

کلیدواژه ها:

NEPCM ، Heat transfer ، free convection ، Hot circulars ، Finite element method