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--- en:grundlagenhandbuch:drehmoment_und_antriebsleistung:enthalpiemodell:feststofffoerderzone [2025/06/20 09:36] – deppe2
+++ en:grundlagenhandbuch:drehmoment_und_antriebsleistung:enthalpiemodell:feststofffoerderzone [2026/01/27 15:37] (aktuell) – gelöscht deppe2
@@ Zeile 1: / Zeile 1: @@
-====== Solids conveying zone ======
-===== Solids conveying zone =====
-First of all, a specific enthalpy curve of a semi-crystalline plastic is considered (Picture 1). At the crystallite melting temperature, the plastic has a corresponding specific enthalpy depending on the type. This enthalpy is divided in PAM into $\Delta h_f$ solid enthalpy (enthalpy change to increase the solid temperature) and $\Delta h_a$ melting enthalpy (enthalpy required to dissolve the crystalline regions).
-**Picture 1:** Specific enthalpy curve of a partially crystalline polymer
-The specific enthalpy change at a supporting point compared to the filling point of the material results from the multiplication of the solid enthalpy by a percentage factor which is dependent on the filling temperature, the current solid temperature and the crystallite melting temperature. The factor indicates to what percentage of the crystallite melting temperature the solid was heated, starting from the starting temperature of the material. The melting enthalpy is initially not taken into account in the solids conveying zone. The reason is shown in figure 1. For the determination of the enthalpy increase must be referred to the black imaginary straight lines. If the melting enthalpy is taken into account, the straight line would have a too large gradient at low temperatures, resulting in too large a deviation. In the solids conveying range, however, the temperature increase lies precisely in this small value range. Formally expressed, the specific enthalpy change at a support point in the solids conveying range compared to the filling point is given by equation 0-1
-$$\Delta h_{FF} = \Delta h_f \cdot \frac{T_{FS} - T_E}{T_K - 0}\tag{Equation 0-1}$$
-For the driving power of an element area the difference of the specific enthalpy change between two supporting points is calculated with equation 0-2.
-$$\Delta \Delta h_{FF} = \Delta h_{FF_n} - \Delta h_{FF_{n-1}}\tag{Equation 0-2}$$
-Using the calculated specific enthalpy difference, the pressure difference and the introduced heat flow, the required drive power required between two support points in the solids transport zone can be calculated from this (equation 0-3).
-$$P_{D/FF} = \dot{m} \ast (\Delta \Delta h_{FF} + \frac{\Delta p}{\rho}) - \dot{Q}\tag{Equation 0-1}$$