Effect of product related parameters on heat-transfer rates to canned particulate non-Newtonian fluids (CMC) during reciprocation agitation thermal processing

Effect of product parameters (particle size, shape, density and concentration) on overall (U) and fluid-to-particle (h(fp)) heat transfer coefficients during reciprocating agitation thermal processing of canned particulate non-Newtonian fluid (1% CMC) mixtures were evaluated at various reciprocation frequencies using two full-factorial (3 x 3 x 3) experimental designs. Analysis of variance of results revealed that all parameters significantly affected (p < 0.001) U and h(fp). Larger size particles depicted lower U and h(fp), due to decrease in surface area per unit volume ratio. While Teflon particles had lowest heating rate index, Nylon particles depicted highest U and h(fp). This trend was explained by the fact that rate of temperature increase was better correlated with thermal diffusivity while U & h(fp), were better correlated with thermal effusivity. The magnitude of U and h(fp), associated with the three shapes varied in the following order: cube > sphere > cylinder. U and h(fp) values increased up to an optimal particle concentration of 20% and 30%, respectively, but decreased at higher particle concentrations. (C) 2015 Elsevier Ltd. All rights reserved.