Uniqueness and drag for fluids of second grade in steady motion Academic Article uri icon


  • For incompressible fluids of second grade that are compatible with the Clausius-Duhem inequality, non-uniqueness of steady flows with small Reynolds number (i.e. creeping flows) is possible provided the 'absorption number' is also small. We discuss this uniqueness question, generalize a well-known theorem of Tanner concerning how solutions of the Stokes equations may be used to generate solutions of the creeping flow equations for fluids of second grade, and give a new uniqueness theorem appropriate to a class of problems for the steady creeping flow of fluids of second grade. Under the conditions for uniqueness, we obtain a simple formula for the drag force on a fixed body which is immersed in a fluid of second grade which is undergoing uniform creeping flow. For bodies with certain geometric symmetries, the non-Newtonian nature of the fluid has no effect upon the drag. 1978.

published proceedings

  • International Journal of Non-Linear Mechanics

author list (cited authors)

  • Fosdick, R. L., & Rajagopal, K. R.

citation count

  • 72

complete list of authors

  • Fosdick, RL||Rajagopal, KR

publication date

  • January 1978