REACT program evaluation

In solving the underlying model problem, the Jacobian matrix is an iteration matrix used in a modified Newton iteration. Thus it usually doesn t need to be computed too accurately or updated frequently. The Jacobian s role in sensitivity analysis is quite different. Here it is a coefficient in the definition of the sensitivity equations, as is 3f/9a matrix. Thus accurate computation of the sensitivity coefficients depends on accurate evaluation of these coefficient matrices. In general, for chemically reacting flow problems, it is usually difficult and often impractical to derive and program analytic expressions for the derivative matrices. However, advances in automatic-differentiation software are proving valuable for this task [36]. 

E. Riber, M. Garcia., V. Moureau, H. Pitsch, O. Simonin, and T. Poinsot. Evaluation of numerical strategies for LES of two-phase reacting flows. In Proc. of the Summer Program, pages 197-211. Center for Turbulence Research, NASA Ames/Stanford Univ., 2006. 

The boranes react very exothermically with oxygen and were once evaluated as potential fuels for rockets in the U.S. space program. 

Regarding the SCR catalyst substrate support, today, SCR substrates generally have 300 and 400 cells/square inch (300- and 400-csi). Heibel [43] showed that in the mass transfer controlled regime (230-350 °C), 600-csi substrates react 35 % faster than 400-csi catalysts. Substrates with higher cell densities are being evaluated in advanced programs for improved deNOx performance. 

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