Abstract Driscoll 9529203 The objective of the proposed research is to quantify and model the complex chemistry and stretch effects that occur within a premixed flame as it undergoes a turbulent wrinkling process. This proposal is a continuation of a previously NSF funded program. The PI plans to make use of a variety of laser diagnostic techniques to investigate two model problems relevant to premixed turbulent combustion. These unique flame experiments include: (1) the interaction of a flame front with an isolated vortex, and (2) the flame propagation in an isotropic homogeneous turbulent flow in a long channel, generated by a set of fans. The PI plans to measure profiles of important radical species, including CH, OH, O and H, and the stretch rates and vorticity along a premixed flame as it undergoes an unsteady wrinkling process. He also plans to obtain advanced Direct Numerical Simulations (DNS) with complex chemistry and compare results to both the flame-vortex and the homogeneous turbulence experiments, and to use the results to measure quantities that are required by other types of models.