Rheological behavior of suspensions of randomly oriented rods: 3, Viscometer for opaque suspensions
With falling-ball rheometry, we have measured the apparent relative viscosity of suspensions of large, neutrally buoyant, rigid rods in a viscous Newtonian fluid, while approximately maintaining the rods in a randomly oriented configuration. A new technique for measuring the time of flight of a ball between two positions is used. This technique, based on an eddy-current detector, enables us to determine the position of a metallic (non-magnetic) ball falling through an opaque suspension, with an estimated inaccuracy of less than 1.5%. An electric signal, which peaks when the ball passes through the plane of the magnetic field, and the elapsed time are recorded using a computerized data acquisition system. The viscosities of two suspensions of different aspect ratio rods are compared at a particle volume fraction of 0.05.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (USA); Los Alamos National Lab., NM (USA)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 6955272
- Report Number(s):
- SAND-87-2059C; CONF-880827-1; LA-UR-88-583; ON: DE88005625
- Country of Publication:
- United States
- Language:
- English
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