Direct sensitivity analysis for ignition delay times

The sensitivity coefficients of ignition delay time with respect to chemical kinetic rate parameters is traditionally calculated using a brute force approach wherein the number of initial value problems solved is no fewer than the number of rate parameters. By reformulating the underlying initial value problem as a boundary value problem, it is shown that the sensitivity coefficients can be extracted directly, accelerating thus the computational time by at least an order of magnitude. This has far reaching consequences in kinetic model development and optimization, especially when a large number of rate constants are involved.