Parametric Investigation of the Roughness of MEPCM Particles Suspended in a Fluid Flowing in a Circular Tube

This paper reports on a parametric investigation of the effect of the microencapsulated phase change material (MEPCM) particle roughness on the heat transfer characteristics of an MEPCM slurry. The MEPCM slurry is hydrodynamically fully-developed and flows in a circular tube under laminar conditions with a constant heat flux boundary condition. Three roughness shapes were investigated and six parameters were analyzed to determine their effect on the heat transfer characteristics of the MEPCM slurry. Results show that the MEPCM particle roughness does have an effect on the heat transfer characteristics of the MEPCM slurry since the average Nusselt number (Nuaν) increases by up to 7.23% compared to that of the conventional MEPCM particle. Furthermore, the dimensionless perimeter of the MEPCM particle with roughness was found to increase by up to 110.47% compared to that of the conventional MEPCM particle while keeping the MEPCM particle area constant. Results also show that the rectangular roughness shape has the most effect on the average Nusselt number Nuaν compared to those of the other investigated roughness shapes. This paper provides a different perspective in the field of MEPCM slurries by raising awareness regarding the significance of the particle roughness for future numerical and experimental studies with the goal of increasing the accuracy of the model and developing new varieties of rough MEPCM particles that would enhance heat transfer.