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On page 1103, the published paper omitted important text before and after figure 6.

Parameter tuning was performed against data from a full scale engine rig with a Diesel Oxidation Catalysts (DOC). Several different catalyst configurations were used with varying Pt loading, washcoat thickness and volume. To illustrate the interplay between kinetics and mass transport, engine operating points were chosen with a wide variation in variables (inlet conditions) and both transient and stationary operation was used. A catalyst model was developed where the catalyst washcoat was discretized as tanks in series both radially and axially. Three different model configurations were used for parameter tuning, evaluating three different approaches to modeling of internal transport resistance. It was concluded that for a catalyst model with internal transport resistance the best fit could be achieved if some parameters affecting the internal mass transport were tuned in addition to the kinetic parameters.

When performing catalyst modeling and parameter tuning it is desirable that the experimental data contain both transient and stationary points and can be generated over a short period of time. Here a method of creating such concentration transients for a full scale engine rig system is presented. The paper describes a valuable approach for changing the composition of engine exhaust gas going to a DOC (or potentially any other device) by conditioning the exhaust gas with an additional upstream DOC and/or SCR. By controlling the urea injection and the DOC bypass a wide range of exhaust compositions, not possible by only controlling the engine, could be achieved. This will improve the possibilities for parameter estimation for the modeling of the DOC.

This work concerns exhaust gas cleaning for heavy-duty diesel engines by means of NOx storage and reduction technology. A full-scale engine rig has been constructed and stationary NOx reduction tests performed. In the NOx storage and reduction approach, NOx is stored on a BaO surface as Ba(NO3)2 under long lean conditions and desorbed and reduced under short rich conditions. The rich conditions are created by injection of diesel fuel into the exhaust stream. The stationary NOx reduction tests have been performed at nine load points on an engine rig. They have shown that a stationary NOx reduction of between 25-53% is achievable at most load points depending on the temperature. The high oxygen content in the exhaust gas leads to the oxidation of the injected hydrocarbons and thus to a high fuel penalty. To lower the fuel consumption, the mass flow through the catalyst has been reduced under the regeneration periods. This was done using a bypass system with a pneumatic valve control.