Design Of Large-Scale Composite Mould With Inside Circulating Water Heating System

Composite rotor blades are one of the most important parts in a set of wind turbine. Large-scale blades could not be heated in traditional way when produced. That leads to long resin thermal curing time.Circulating water system was chosen as the inner heat source for composite mould of wind turbine blades in this paper. A simplified heat transient model was developed based on the analysis to the real heat transfer process of the mould. Finite element method (FEM) was adopted to solve the transient state temperature field of the model under different status. Results of numerical analysis indicate that, pipe materials and water flowage in pipe have little effect on mould heating results, mould with CFRP structure layer, higher environment temperature, thinner pipe wall, smaller pipe inner diameter and shorter pipe spacing do good to heating, and changes of circulating water temperature, structure and insulating layer thickness produce both advantages and disadvantages to heating.Design parameters of composite mould with inside heating pipeline were optimized in ANSYS optimization module and part of the mould for a wind turbine blade was made with optimized parameters.It shows that mould temperature field evaluation indexes are mainly anastomotic for measured values and calculated ones, which indicates the design method based on FEM in this paper could be adopted in project practice. Composite specimens were made and tested, of which one cured in room temperature and the other heated by circulating water system. Comparison to the former, the latter saved curing time by 75% and fiber steeping time by 42%, got thinner by 2.79%, increased curing degree by 9% and improved mechanic properties by 36～57%. The results above prove that the mould with inside circulating water heating system can take a great advantage to composite product preparation.