VISCOSITY MEASUREMENT, constant torque:

This is not the usual method. Conventional instruments step from one constant stirring rate to another to gather data by measuring the torque. It is better for fluids with time-dependent behavior to step from one constant torque to another. At each constant torque, the rate is recorded to get the apparent viscosity. This is a very nice way to gather data on these fluids that have viscosity dependent on time. For example, a plot of apparent viscosity versus time may show creep, a term for change with time. Data at different torques would help determine the stress at which something such as catsup would begin to flow.

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