A simple and popular model for two nonnewtonian fluids in Fig. 1.8a is the power-law:
where C and n arc constants fit to the fluid [16]. From Fig. 1.8a, deduee the values of the exponent n for which the fluid is (a) newtonian, (b) dilatant, and (c) pseudoplas-tic. Consider the specific model constant C = 0.4 N · sn/m3, with the fluid being sheared between two parallel plates as in Fig. 1.7. If the shear stress in the fluid is 1200 Pa, find the velocity V of the upper plate for the eases (d) n = 1.0, (e) n = 1.2, and (f) n = 0.8.
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