Assessment of different chemistry reduction methods based on principal component analysis: Comparison of the MG-PCA and score-PCA approaches

Two families of PCA based combustion model were recently developed: score-PCA and MG-PCA. This paper presents the first comparative study of the two aftermentioned methods. Both methods are first benchmarked on 1-D laminar flames of hydrogen-air and syngas-air, to verify the consistency of the approaches. The sensitivity to differential diffusion is carefully addressed and a rotation technique is proposed, to allow for using score-PCA with differential diffusion. Then, 2-D flame-turbulence interactions are considered, spanning a wide range of velocity and length scale ratios, to demonstrate the ability of PC-based combustion models to efficiently capture the behavior of different combustion regimes, from flamelet-like flames to distributed reaction regimes.