| With the deterioration of ecological environment and the shortage of environmental resource, human beings pay more attention to the environmental protection and energy conservation. The rule of law established for emission of internal combustion engine (ICE) is stricter; the competition of energy-saving technology among ICE plants is more violent. Therefore, energy-saving and emission decrease are the development objects of ICE. Introducing into Functionally Gradient Materials (FGM), integrating the emulsive combustion technology with the catalytic combustion technology, Ceramic/Metal Gradient Thermal Barrier Coatings (TBC) and Catalyst/Ceramic Gradient Environmental Barrier Coatings (EEC) are sequentially sprayed on the inside surface of chamber components of ICE to form Catalysis/Thermal Barrier Functionally Gradient Coatings (TBC-EBC), which can result in reforming catalysis reaction between fuel and steam under relative low temperature (200-500℃) to produce a small quantity of hydrogen gas and improve the combustion process of fuel as well as the emission - behavior, economic performance and the reliability of ICE. This is a new research direction."Conjoining the project of "Research on Design Methods and Manufacture Techniques for Gradient Thermal Barrier Coatings with Environment Protection Function" funded by the Open Foundation from the State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, this paper carried out theoretical analysis and numerical calculation of heat transfer and thermal stress in TBC-EBC. The mathematical model of the steam reforming catalysis reaction on TBC-EBC is established. And, the manufacture techniques and performance evaluation of TBC-EBC are also carried out in experiments.The structure model and the physical property model of TBC-EBC are set forth. In terms of heat transfer theory and thermoelastic theory, multi-layer plate model and multi-layer cylinder model are established for heat transfer and thermal stress analysis in TBC-EBC. They are both composed of four layers, i.e. substrate layer, bond layer,gradient TBC layer and gradient EBC layer, of which the gradient structure of gradient TBC layer and gradient EBC layer adopt polynomial and exponential function model. As for concrete calculation example, the temperature field and the thermal stress field in TBC-EBC are analyzed by analytical solution and the finite element method. The results show that the analytical solution shows good agreement with finite element solution.In order to study the influence from TBC-EBC on energy-saving and emission behavior of ICE, the chemical reaction speed model of reforming catalysis reaction between methane and steam is established in terms of chemical reaction dynamics and multi-phase catalysis theory. The ignition chemical equations of methane/steam reforming catalysis reaction in the pre-catalysis reforming reaction and the surface catalytic reforming reaction are studied. Furthermore, on the basis of experimental data from the steam reforming reaction with aliphatic hydrocarbon and aromatic hydrocarbon, the chemical reaction speed model of reforming catalysis reaction between fuel and steam is established, through which the quantity of hydrogen gas can be obtained. It is very meaningful for the study of the steam reforming reaction' s influence on the combustion process in ICE.According to the structure and performance requirement, TBC-EBC samples and real TBC-EBCs for ICE have been fabricated by plasma spray technique. The samples are observed by scanning electron microscopy (SEM), the components in them are analyzed by X-ray spectroscopy (XRS). And, the catalytic effect of TBC-EBC is appraised. The experiment shows that the sintered catalyst particles were found on the surface of TBC-EBC samples, which will affect the catalysis performance of TBC-EBC. As a result, the modified measures and the post treatment are put forward in order to provide foundation for the successful fabrication of TBC-EBC.
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