The NSR (NOx storage and reduction) technology is one of the most promising methods for removing NOx from next-generation lean-burn and diesel engines. Three major drawbacks, including the low temperature activity, the catalyst sulfur tolerance and the use of the large amount of the noble metals for the commercial application of NSR catalytic system, may be resolved by the development of a better catalytic system through a fast assay method in line with the combinatorial chemistry technique. The colorimetric method is the most effective way for screening a large number of the catalyst samples at once, although an appropriate dye for revealing the color specific to NOx should be examined in advance. A knowledgebased colorimetric methodology for screening a better NSR catalyst by combinatorial approach has been developed and validated by the experimental results determined by means of traditional, time-consuming techniques such as TPD.

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In this study, the temperature and thermal stress fields of an internal combustion hot blast stove were calculated and analysed. Turbulent, species transport, chemical reaction, radiation, and porous media models were implemented in a computational fluid dynamics model. Thermal boundary conditions on the structure of the hot blast stove were calculated based on the analytic adiabatic Y-plus method. A method to interpolate the thermal boundary conditions to a finite element mesh was developed, and the boundary conditions were mapped through the proposed method. In the on-gas period, the vortex was generated in the dome, and it made the variation of the temperature field in the checker chamber. The maximum temperature of the flue gas reached 1841 K in the on-gas period. In the on-blast period, the flow was considerably even compared to the on-gas period, and the average blast temperature reached 1345 K. The outer region of the checker chamber is shown to be continuously exposed to a higher temperature, which makes the region the main domain in managing the deterioration of the refractory linings. The shell temperature did not change during the operation due to the lower thermal diffusivity of the refractory linings, where the inner surface of the refractory had a maximum temperature change from 1441 K to 1659 K. The maximum temperature of the shell was 418.4 K at the conical region of the checker chamber side. The conical region had the higher maximum and middle principal thermal stresses due to the presence of a large temperature gradient around the conical region, where the largest maximum and middle principal stresses were 300.6 MPa and 192.0 MPa, respectively. The conical region was found to be a significant area of interest where it had a higher temperature and thermal stress.