Transient Temperature Field Of Composite Functionally Graded Plate Under A Variety Of Thermal Boundary

Functional graded materials (FGM) is a new type of heterogeneous composites material, its chemical composition, microstructure and atomic arrangement show continuous gradient change from one side to the other side, so that the nature and function of the material change in the same way. It has incomparable superiority that many traditional materials don’t have. So it is widely used in the field of aerospace, nuclear reactors, the internal combustion engine and so on.The paper selected folder FGM metal/ceramic composite plate as a research object. The main research problems were as follows:(1) According to the theory of heat conduction and the view of the computational heat transfer, the finite element algorithm for the transient temperature field problem in the folder FGM metal/ceramic composite plate under a variety of thermal boundary conditions was researched. It took variational finite element method in the spatial domain and took finite difference method in the time domain. By using linear interpolation function the finite element basic equations of temperature field were derived and the computer program that can solve the basic equations of the finite element using advanced computer language FORTRAN was written.(2) Assume that the initial temperature To=300K, the temperature of the metal layer Ta=770K, the temperature of the ceramic layer Tb=1680K, the distribution shape factor of the material component M=1, the porosity A=0and so on. We can obtain that the transient temperature distribution in different moments and compare it with the one from references, the correctness of the method and the computer program used in this paper were examined.(3) The paper researches the influences of the heating and cooling and the convection heat transfer coefficient and the gradient layer composition and the porosity and the geometry on the one-dimensional transient temperature field and researches the moderating role of the FGM metal/ceramic composite plate for heat conduction.By numerical calculation, the results are as follows.(1) Gradient layer affects the transient temperature field of FGM metal/ceramic composite plate under convective heat transfer and heating conditions. It can make transient temperature field distribution curve more gentle, and with the increase in gradient layer thickness, the curve can be more flatten.(2) The FGM layer porosity has obvious impact on the distribution curve of the transient temperature field of folder FGM metal/ceramic composite plate under heating and cooling conditions. If the porosity is greater, the steeper the curve will be.(3) The convection heat transfer coefficient ha and hb has significant impact on the transient temperature field distribution of the folder FGM metal/ceramic composite plate. The smaller the convection heat transfer coefficient is, the more relaxed the curve of the transient temperature field of functionally graded composite plate is. The greater the convection heat transfer coefficient is, the steeper the curve will be.(4) The change of FGM material component distribution shape coefficient M has obvious impact on the transient temperature field distribution of folder FGM metal/ceramic composite plate during heating process. The distribution coefficient is larger, the more relaxed the curve will be. The smaller distribution coefficient is, the steeper the curve will be.