Dd. Joseph et J. Feng, A NOTE ON THE FORCES THAT MOVE PARTICLES IN A 2ND-ORDER FLUID, Journal of non-Newtonian fluid mechanics, 64(2-3), 1996, pp. 299-302
In this note we show that the normal stresses on a solid body in plane
flow of a second-order fluid are compressive and such as to turn long
bodies into the stream and to cause circular particles to aggregate a
nd chain.