Investigation of the Effect of Correlated Uncertain Rate Parameters on a Model of Hydrogen Combustion Using a Generalized HDMR method

Abstract The High Dimensional Model Representation (HDMR) method has been applied in several previous studies to obtain global sensitivity indices of uncorrelated model parameters in combustion systems. The method is based on a decomposition of the model output in terms of a hierarchy of cooperative effects among the model inputs, which is unique when the input parameters are independent. However, many combustion systems will contain correlated input parameters. The development of a generalized HDMR method is therefore presented here, which uses the Rosenblatt transformation on a correlated model parameter sample to obtain a sample of independent parameters. The generalized HDMR method is used for the determination of sensitivity indices of a hydrogen combustion model with 33 correlated input parameters for a given set of experimental conditions. The effect of the correlation of rate parameters on the calculated sensitivity indices of ignition delay times is investigated.