TA Instruments TMA 2940 CE, Руководство оператора

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Using Your Options
TA I
NSTRUMENTS
TMA 2940 CE 4–46
η
=
Calculations for Viscosity and Wall
Shear Rate Data
To calculate sample viscosity (
η
) and wall shear
rate (
γ
), the experimental data is first scaled and
corrected for expansion of the parallel plates (as
previously shown on page 4-43). Then this
corrected data is applied to equations developed
by Dienes and Klemm ( J. Appl. Phys. , 17, 458,
1946) and Cessna and Jabloner ( J. Elast. Plast. ,
6, 103, 1974).
Equation:
4 F
∆
t
x x
10 6 mm 2 /m 2
3
π
r
4
∆
(1/ h
2
)
3 rh
∆
(1/ h
2
)
2
∆
t
where:
F = applied force (N)
r = parallel plate radius (mm)
h = sample height (mm)
t = time (sec)
η
= viscosity (Pa-sec)
γ
= shear rate (1/sec)
γ
=
x
•
•