Numerical investigation on heat transfer performance of a confined slot jet impingement with different MEPCM-water slurries using two-phase Eulerian–Eulerian model

Abstract

An in-house Fortran-based two-phase Eulerian–Eulerian solver is used to study an impinging jet with microencapsulated phase change material (MEPCM)-water slurry in a minichannel. The heat transfer performance of water based n-eicosane and n-octadecane MEPCM slurries are reported here. The melting pattern of the particles within the minichannel are also reported at different parameters. Figure of merit (FOM) is used to quantify the heat transfer performance of the MEPCM-water slurry taking into account both the thermal and flow characteristics of the slurry. The heat transfer enhancement around 72% is found in the average Nusselt number for a 5%-n-eicosane water slurry, compared to that of pure water at a jet Reynolds number of 200. The melting region of MEPCM particles is found to come closer to the heated walls with an increase in Reynolds number. An increase in the Reynolds number from 100 to 300 has brought an increment of around 81% in the Nusselt number at the jet impinging region, while the increment in the average Nusselt number is around 145%. The figure of merit (FOM), increases from 1.34 to 1.64 with an increase in particle concentration from 1% to 10%, at Re = 300. By comparing the figure of merit values, the best heat transfer performance compared to pure water is obtained for water-based n-eicosane slurry at Re = 100, and εs=1%. A parametric study involving Reynolds number, particle concentration, and channel height to jet width ratio has been reported. Present results are validated with numerical and experimental results available in the literature.