STRESS TENSOR EXPRESSIONS FOR DISPERSIONS

The derivation of the expression of the Brownian contribution to the s tress tenser in a dispersion of spherical particles is discussed in re lation to the level of description. The result obtained by Batchelor a t the configuration space level is compared with a similar result of B ossis and Brady, derived at the underlying stochastic level from a Lan gevin equation. It is shown that the result of Bossis and Brady may be derived also at the configuration space level. This clarifies the con nection between both approaches and provides a generalization of Batch elor's result. (C) 1995 Society of Rheology.