Temperature Field Simulation Of I-shaped Beam Composites For ADP Process Based On Finite Volume Method

Advanced Pultrusion is one of the important technologies of low cost automation in composite materials,which has the advantages of high production efficiency and no limitation of size,low porosity and so on.In the ADP process,the prepreg directly into the high temperature die,rapid heating and curing into composite material.Thermal chemistry is quite complex in transient temperature field,directly affect the properties of components.However,the process of ADP can only be established through engineering experience,and there is no theoretical support.Therefore,the study of the curing temperature field of composite materials in ADP,has important significance for the improvement of process conditions,the improvement of product quality and the saving of energy loss.The main works of this paper are as follows:First of all,By differential scanning calorimetry(DSC)experiment,with resin curing kinetics as the theoretical foundation,through nonlinear fitting MATLAB,the curing kinetics equation of epoxy resin under non isothermal condition is established.Secondly,According to the technical process and technical conditions of advanced pultrusion process,combined with the differential equation of curing reaction kinetic and the heat conduction,mathematical model of temperature field is established,the boundary conditions and initial conditions are also analyzed,these are all for the preparation of numerical simulation of temperature field.Based on the analysis of the DSC image under the condition of non isothermal,the characteristic temperature of the carbon fiber reinforced epoxy composite in curing process was determined.With the help of Origin,we found that the characteristic temperature and the heating rate show a very good linear relationship.According to this,the precuring temperature and the curing temperature of the simulation process were determined.Finally,this paper aimed at the I-beam model,based on the finite volume method,using Microsoft Visual C++ platform,written the numerical simulation program,studied on the composite heat conduction problem with nonlinear heat source in the two-dimensional state,analysed the history of cure temperature and degree of cure during the curing of prepreg in the advanced pultrusion.This paper detailedly simulated the curing temperature field distribution of the same product in different time,the maximum thickness of different parts,the different fiber volume fraction,the different curing time,and the different curing temperatures.And found the critical thickness of the overheating effect.