BOUNDARY CONDffiONS IN CONTINUUM MECHANICS WITH PARTICULAR REFERENCE TO FLUID BEARINGPOROUSMED

Abstract

This work accomplishes three tasks. First, to model fluid be­ haviour in the thin region (interface) between bulk phase fluid and the porous body saturated by fluid, as:

1. a three dimensional continuum

2. a bidimensional continuum separating two bulk continua.

In the second case, balance relations are motivated for true and surface excess relations in cases of steady and creeping flow, creeping, and general flow. The simplest extension for stresstensor is derived carefully to be symmetric in surface excess balance relations.

Second, to obtain surface balance relations from the molecular viewpoint by applying surface averagi1_1g theorems developed using an in­ terfacial weighting function. Comparison between surface balance rela­ tions obtained by integration of volume balance relations across the inter­ face and relations developed from the molecular viewpoint is accomplished. This helps bringing to evidence the force exerted by the solid body on the fluid.