Flow pattern determination and rheological characteristics of high-density phase change material slurry in homogeneous flow

Abstract

Erythritol slurry has shown great potential as a heat transport medium. We investigated the versatility of the flow pattern determination method and the effect of gravity on the rheological characteristics of erythritol slurry, with a focus on homogeneous flow. In vertical flow, the flow pattern was always homogeneous, whereas in horizontal flow, it depended on the flow velocity. Thus, the plots obtained from the horizontal flow were divided into two parts using linear regression analysis, and the discussion focused on the homogeneous part, which is the high-velocity region. Erythritol slurry behaved as a power law fluid in a homogeneous flow, regardless of the flow direction. However, the viscosity indices differed in the vertical and horizontal flows. The non-Newtonian behavior became more pronounced in the horizontal flow than in vertical flow. These findings may be valuable for the design and optimization of heat transport systems that use high-density PCM slurry.