Unterschiede
Hier werden die Unterschiede zwischen zwei Versionen angezeigt.
| Beide Seiten der vorigen RevisionVorhergehende Überarbeitung | |||
| en:grundlagenhandbuch:scale-up:modelluebertragung:konstante_spezifische_leistung [2025/06/22 11:07] – deppe2 | en:grundlagenhandbuch:scale-up:modelluebertragung:konstante_spezifische_leistung [2026/01/21 08:45] (aktuell) – gelöscht admin | ||
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| - | ====== Constant Specific Energy ====== | ||
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| - | ===== Constant Specific Energy ===== | ||
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| - | The starting point for this approach is the characteristic value Π5. of the melt conveying zone (see table). By assuming a constant melt temperature at the screw tip and in conjunction with the requirements specified beforehand (see table), the viscosity ratio of model design and main design results: | ||
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| - | $$\frac{\eta}{\eta_0} = \left(\frac{D}{D_0}\right)^{2\psi+\chi-2-\omega} \tag{1}$$ | ||
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| - | Furthermore, | ||
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| - | $$\frac{\dot{\gamma}}{\dot{\gamma}_0} = \left(\frac{D}{D_0}\right)^{1-\psi-\chi} \tag{2}$$ | ||
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| - | If both terms are logarithmized and the diameter ratio is eliminated, one receives: | ||
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| - | $$\lg\frac{\eta}{\eta_0} = \frac{2\psi + \chi - 2 - \omega}{1 - \psi - \chi} \lg\frac{\dot{\gamma}}{\dot{\gamma}_0} \tag{3}$$ | ||
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| - | According to Equation 1, at a constant temperature for the viscosity function it also applies: | ||
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| - | $$\lg\frac{\eta}{\eta_0} = (n - 1) \lg\frac{\dot{\gamma}}{\dot{\gamma}_0} \tag{4}$$ | ||
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| - | By that method the screw speed exponent for a constant specific energy input derives: | ||
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| - | $$\chi = \frac{n - n\psi + 1 + \omega - \psi}{n} \tag{5}$$ | ||
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| - | By inserting the screw speed exponent into Eq. $\frac{\dot{m}}{\dot{m}_0} = \frac{\dot{V}}{\dot{V}_0} = \left(\frac{D}{D_0}\right)^{2+\psi-\chi}$ the respective throughput for this operating point results. | ||