Análisis del proceso de enfriamiento de un molde de estirado-soplado mediante simulación para un envase de 500ml

Abstract

In the present research, the focus was on analyzing the thermal behavior of the stretch-blow mold at various points during the cooling process, using simulation software. The design of the mold and the 500 ml container was carried out in SolidWorks, while the thermal study was conducted in ANSYS Fluent. The simulation parameters were determined analytically through heat transfer equations, employing Fourier's law and Newton's law of cooling. These equations were fundamental for obtaining the input data for the software, and the material properties of the mold and the container were obtained from tables at the desired temperatures for the simulation. To evaluate the thermal behavior at different points, the mold was divided into three planes with depths of 10 mm, 19 mm, and 37 mm. These measurements allowed for the determination of temperatures in the mold's cooling system for a 500 ml container. At a depth of 37 mm is the cooling system, where the water flow transfers and dissipates the heat generated by the environment and the PET container cooling process, maintaining the mold at temperatures between 16 °C and 20 °C. At the 19 mm plane, an intermediate point between the cooling system and the ambient temperature, a heat conduction process is observed with temperatures ranging from 26 °C to 40 °C. At the 10 mm plane, near the contact point with the bottle, a temperature increase is noted due to the container's heat, with ranges from 90 °C to 97 °C and a maximum mold temperature of 83 °C in certain areas. The cooling system design was based on a pre-existing model, adapted with changes in internal dimensions to improve mold cooling. The internal dimensions, with three cuts (two vertical and one horizontal) that connect to each other, allowed for a more homogeneous water flow distribution, minimizing temperature variations. This approach aimed to ensure that the PET container was molded adequately, avoiding issues such as excessive crystallization or material fragility, which are crucial for efficient production and high-quality final products.