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The present article proposes to show the mathematical design of a spindle and the speed that it requires, using mathematical formulas, to carry out the extrusion process of recycled PETG or HDPE plastic. Speed control in this process is of great importance because the quality of the filament to be obtained will depend on it. The study will be simulated on spindles and casing that are 3640 and 3890 mm long respectively and made of AISI 4140 steel. The spindle casing has 3 types of band resistors, which vary their temperature according to the material to be used: PETG plastic or HDPE plastic. Each band type resistor is found in each section that the spindle has; the screw has 3 stages called the feeding zone, the compression zone, and the dosing zone. The production capacity is 40 kg /h of PETG or HDPE plastic filament 3 mm thick. In conclusion, the present method consists of the mathemati...

The present article delves into the comprehensive study of internal flow dynamics within a cryogenic chamber used for freezing food with high water percent. For cryogenic freezing is necessary to reduce temperature extremely and maintain a uniform distribution, different behaviours may cause structural damages on food. This is because the chamber comprises a circular-sectioned tunnel or chamber coupled with a set of Jet-type atomizers for the injection of liquid nitrogen. The internal flow, predominantly consisting of liquid nitrogen, necessitates prolonged residency within the chamber to uniformly and effectively cool or freeze food traversing its interior. Consequently, the primary aim is to extend the cryogenic fluid's residence time, achieved by strategically decelerating the flow. This deceleration is orchestrated through the strategic injection of the fluid to induce a swirling or ...

This article addresses the study of internal flow dynamics within a cryogenic chamber designed for freezing food using liquid nitrogen injection. The chamber features a circular section with strategically placed jet-type atomizers for this purpose. The primary objective is to extend the residence time of the cryogenic fluid within the chamber to ensure uniform and effective freezing of the passing food items. This is achieved by inducing a swirl effect through strategic deceleration of the flow using the atomizers. The meticulous placement of these atomizers at periodic intervals along the internal walls of the cylindrical chamber ensures prolonged recirculation of the internal flow. Internal temperature analysis is crucial to ensure the freezing process. The study is supported by numerical analysis in CFD ANSYS to assess the dynamics of the swirl effect and parameters associated with th...