Читать книгу The Rheology Handbook - Thomas Mezger - Страница 170

Preset

1 With controlled shear rate (CSR): γ ̇ = const (see Figure 3.34), and time-dependent temperature profile T(t), e. g. as an upward or downward ramp

2 With controlled shear stress (CSS): τ = const (similar to Figure 3.34), and time-dependent temperature profile T(t), e. g. as an upward or downward ramp

Result

Function of τ (or γ ̇ , respectively) and η dependent on the temperature (as in Figures 3.35 to 3.37, if time t is replaced by temperature T on the x-axis; see also Figures 3.46 and 3.47).

The shape of the curves of τ(T) and η(T) are similar because τ and η are proportional since

τ = η ⋅ γ ̇ (here with γ ̇ = const). However, the curves of the functions of γ ̇ (T) and η(T) show an

inverse shape since γ ̇ and η are inversely proportional (since η = τ/ γ ̇ , here with τ = const).

Figure 3.46: Temperature-dependent viscosity curve