Aspects of Efficient Parameter Estimation for Diesel Oxidation Catalysts

Sammanfattning: In this thesis the objective was to tune the model parameters of diesel oxidation catalysts (DOC) to measurement data from engine rig experiments in an efficient manner. The scope was however not limited to the algorithm of parameter search alone but instead included the whole process starting with the design of experiments. Different aspects of efficient parameter estimation of a full scale DOC were evaluated. This included different kinetic models, mass transfer resistance evaluation, experiments at both engine rig and lab scale, and parameter estimation algorithms. A specially developed detailed kinetic model, a method for parameter estimation using Multivariate Data Analysis, and a method for full scale engine rig experiments were all important products. In addition to these outputs some relevant conclusions were made based on the studies • Including internal mass transport parameter in the tuning improved the possibilities of achieving a good fit for the catalyst model • If internal mass transport is to be modeled the kinetic model cannot include parameters mimicking the effects of transport resistance • A detailed kinetic model improves the conditions for separating kinetics and mass transport but also increases the need for experimen-tal complexity at the same time as model instability may increase