Unterschiede
Hier werden die Unterschiede zwischen zwei Versionen angezeigt.
| Beide Seiten der vorigen RevisionVorhergehende ÜberarbeitungNächste Überarbeitung | Vorhergehende Überarbeitung | ||
| en:berechnungen:einfache_berechnung [2024/10/27 19:58] – neelest | en:berechnungen:einfache_berechnung [2026/09/17 09:23] (aktuell) – gelöscht - Externe Bearbeitung (Unbekanntes Datum) 127.0.0.1 | ||
|---|---|---|---|
| Zeile 1: | Zeile 1: | ||
| - | ======Regular calculation ====== | ||
| - | ===== Starting a calculation ===== | ||
| - | |||
| - | There are two ways to start the calculation \\ | ||
| - | - With selection of the calculation and process settings | ||
| - | - Quick calculation with the last used calculation and process settings | ||
| - | |||
| - | {{ : | ||
| - | |||
| - | The first selection opens a window in which the process parameters and the calculation settings can be changed. The settings are presented below. | ||
| - | Confirming the // | ||
| - | |||
| - | With the 2nd selection, the last known process and calculation settings are used and the progress and report display appears immediately. | ||
| - | |||
| - | {{ : | ||
| - | |||
| - | The calculation log appears in the upper part of the progress and report display. The calculation process can be recognised by the sequence at the bottom of the window. \\ | ||
| - | Here means: \\ | ||
| - | * **Green**: Successful calculation | ||
| - | * **Orange**: Warning message | ||
| - | * **Red**: Error message | ||
| - | |||
| - | By clicking on an orange or red field, the log jumps directly to the corresponding warning or error message. | ||
| - | |||
| - | ==== Process parameters ==== | ||
| - | |||
| - | A distinction is made between required and optional process parameters. \\ | ||
| - | The necessary parameters are required for a calculation. \\ | ||
| - | Optional parameters are voluntary inputs that can lead to improved simulation accuracy if the process variables are known. | ||
| - | === Necessary process parameters === | ||
| - | |||
| - | {{ : | ||
| - | |||
| - | The necessary process parameters require the following inputs: | ||
| - | * Optional specification of a circumferential speed/screw speed **OR** specification of a throughput (speed-orientated). \\ If the mass throughput is specified, the speed is calculated iteratively so that the specified throughput is achieved. \\ The specification of a throughput together with a speed is possible via the optional specification of the mass throughput. | ||
| - | * Pressure at the screw tip (specified or mould characteristic curve if a mould is defined) | ||
| - | * Pressure at the front edge of the hopper | ||
| - | * Specification of the final melt temperature (for an initial temperature profile, see also ‘Iterate temperature’ in the calculation settings) | ||
| - | * Raw material inlet temperature | ||
| - | === Optional process parameters === | ||
| - | |||
| - | {{ : | ||
| - | |||
| - | Values can be entered for the optional process parameters with the aim of achieving a more precise calculation accuracy. The following can be specified: | ||
| - | * Location of the melt vortex formation (OSW). Melting begins at this point | ||
| - | * Start of disperse melting. From this point at the latest** the calculation continues with the disperse melting model | ||
| - | * Throughput (at a specified speed) | ||
| - | * Parameters for the characteristic curve field. 3 speeds and 3 back pressures can be specified here so that characteristic curves for the extruder can be calculated automatically in a full factorial test plan (9 test points) (not yet implemented in REXng) | ||
| - | |||
| - | {{ : | ||
| - | |||
| - | ==== Calculation settings ==== | ||
| - | |||
| - | {{ : | ||
| - | |||
| - | The calculation settings are divided into 4 sections: | ||
| - | |||
| - | === Throughput === | ||
| - | * see also [[calculations: | ||
| - | |||
| - | Three basic settings are possible here \\ | ||
| - | * **Melt dominated**: | ||
| - | * **Coupling solids conveying**: | ||
| - | * **Slot bushing**: the throughput is determined by the | ||
| - | [[en: | ||
| - | |||
| - | If a grooved bush is defined, you can also select whether the calculation | ||
| - | * **Conveyor stiffness** (default) or | ||
| - | * **limit speed orientated** | ||
| - | and the conveying case differentiation can also be selected. | ||
| - | |||
| - | You can also select whether the throughput calculation should take [[en: | ||
| - | |||
| - | For **screws with barrier zones**, there are two options for calculating the pressure throughput | ||
| - | * The **analytical nodal point method**: based on network theory, standard | ||
| - | * Assumption of a **constant pressure gradient** between the solids and melt channel | ||
| - | |||
| - | If a **barrier zone becomes blocked** (solids bed width y in the solids channel achieved by compressing the channel over 100% channel width, **within** a barrier zone), the following options are available | ||
| - | * Continued **conventional melting**, in this case the solid changes into the melt channel and conventional melting is calculated in both channels | ||
| - | * **Disperse melting** from the location of the blockage | ||
| - | |||
| - | If solid bed widths of more than 100% **outside** a barrier zone occur, the melting calculation is cancelled with a warning message. | ||
| - | |||
| - | It is also possible to select whether the message of an insufficient feed throughput through the hopper should be displayed or suppressed. It only makes sense to display the message if a hopper has been defined. Otherwise, a round hopper opening the size of the extruder' | ||
| - | |||
| - | === Melting === | ||
| - | * see also [[en: | ||
| - | |||
| - | For degassing screws only, three options can be selected: | ||
| - | * **to degassing zone**: Standard, the melting calculation stops at the first degassing zone | ||
| - | * **from degassing zone conventional**: | ||
| - | * **from degassing zone disperse**: disperse melting in/after the degassing zone | ||
| - | |||
| - | === Temperature === | ||
| - | * see also [[en: | ||
| - | |||
| - | * If //Iterate temperature// | ||
| - | * If an internal temperature control is defined, the calculation of the internal temperature control can be activated or deactivated. | ||
| - | |||
| - | === Power === | ||
| - | * See also [[en: | ||
| - | |||
| - | Three power models can be selected: | ||
| - | * Enthalpy | ||
| - | * Isothermal | ||
| - | * Non-isothermal | ||
| - | |||
| - | ==== Check ==== | ||
| - | |||
| - | {{ : | ||
| - | |||
| - | The //Check// overview summarises which curves and parameters can be calculated (green tick) or cannot be calculated (exclamation mark). \\ | ||
| - | Click on the exclamation mark to display the reason why a curve or parameter cannot be calculated. | ||
| - | |||
| - | ===Further topics=== | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||
| - | * [[en: | ||