Fuel. blends are widely utilized in high-performance combustion engines and surrogate fuel models. It is essential to Understand thoroughly the fundamental. combustion properties such as the ignition delay time, laminar flame speed, and, extinction strain irate: of fuel, blends in this Study, the unsteady, ignition process of n-decane/toluene binary fuel blends is investigated numerically With detailed reaction mechanism and transport properties. The emphasis is spent on assessing the kinetic and transport effects of toluene addition on the premixed and nonpremixed ignition of n-decane with Two configurations are considered: a static premixed homogeneous configuration to examine the chemical kinetics and a nonpremixed counterflow configuration to assess the effects of kinetics as well as transport. For the homogeneous ignition process, the ignition delay time is found to be strongly affected by the toluene molar fraction in the binary fuel blends. Sensitivity analysis and path analysis are concluded and key elementary reactions involved in the ignition inhibition by toluene addition are identified. For the nonpremixed ignition process, the ignition delay time is shown to be strongly affected by the strain rate as well as the toluene blending ratio. The transport effects on the nonpremixed ignition process are examined with the help of scalar dissipation rate and sensitivity analysis. It is demonstrated that the diffusion transport plays a very important role in the nonpremixed ignition process.