Unterschiede
Hier werden die Unterschiede zwischen zwei Versionen angezeigt.
| Beide Seiten der vorigen RevisionVorhergehende Überarbeitung | |||
| en:grundlagenhandbuch:scale-up:modelluebertragung:konstante_verweilzeit [2025/06/22 11:08] – deppe2 | en:grundlagenhandbuch:scale-up:modelluebertragung:konstante_verweilzeit [2026/01/21 08:47] (aktuell) – gelöscht admin | ||
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| - | ====== Constant Residence Time ====== | ||
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| - | ===== Constant Residence Time ===== | ||
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| - | The medium residence time can be described as a quotient of the free channel volume and the volume throughput. | ||
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| - | $$\bar{t} = \frac{V_{free}}{\dot{V}} \tag{1}$$ | ||
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| - | The substitution of both values by | ||
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| - | $$\dot{V} \sim b h D N \text{ and } V_{free} \sim b h L \tag{2}$$ | ||
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| - | and the formation of the quotient for the model design and for the main design leads to Equation 3. | ||
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| - | $$\frac{\bar{t}}{\bar{t}_0} = \frac{L D_0 N_0}{L_0 D N} = \left(\frac{D}{D_0}\right)^{\psi+\chi} \tag{3}$$ | ||
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| - | To be able to comply with the requirement of a constant residence time of the material in the model design as well as in the main design, the equation | ||
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| - | $$\chi = -\omega \tag{4}$$ | ||
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| - | has to apply. This means that at a constant screw length to diameter ratio (ω = 0) both machines are operated with an identical screw speed. | ||