Abstract: The injection molding process is regarded as a cycle of separate operations linked by certain technological parameters. This paper presents the mathematical model of the nonisothermal flow of polymer compounds through sprue (running) channels of an injection mold, taking into account all main features of the injection molding process. On the basis of this model, an attempt was made to develop a method to optimize the injection phase. Diagrams are plotted, which make a connection between the main technological parameters. Many assumptions were made on the basis of the fact that the flow occurs at low values of the Reynolds number and at a high Peclet number. This allows us to neglect inertia terms in the equation of motion and ignore axial thermal conductivity in the energy equation. The Ellis fluid model is used as a rheological model. Thermal boundary conditions of the first kind and the energy dissipation are taken into account. The flow is accompanied by a chemical reaction that leads to a sharp increase in viscosity. The viscosity is considered to depend on the temperature and the degree of conversion. This, in turn, led to the inclusion of the kinetic equation of a chemical reaction in the mathematical model. It is believed that a chemical reaction takes place in one stage and can be described using a single parameter - the degree of conversion. When a certain critical degree of conversion is reached, the viscosity rushes to infinity and the compound loses its fluidity. The heat output at a chemical reaction is not taken into account. The solution was analyzed numerically by the Galerkin-Kantorovich method according to the iterative scheme. Results of calculations have been presented. |
Keywords and phrases: polymer compounds, mathematical modelling, non-Newtonian fluids, injection molding, chemical reaction.
Received: November 17, 2020; Accepted: December 24, 2020; Published: April 12, 2021
How to cite this article: A. V. Baranov, Optimization of nonisothermal dissipative flow of chemically reacting polymer compounds in the injection molding, JP Journal of Heat and Mass Transfer 22(2) (2021), 191-200. DOI: 10.17654/HM022020191
This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License
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