Single Bank NOx Adsorber for Heavy Duty Diesel Engines 2003-01-1885
In a NOx adsorber programme the feasibility for applying this technology to heavy duty diesel engines was investigated.
After modelling and simulations for realising best λ < 1 engine conditions a platform was build which was used to obtain good NOx adsorber regeneration settings in a number of steady state key points without violating pre-defined limits. With these results the NOx adsorber was evaluated and tested. Besides establishing NOx conversions and BSFC penalties the programme also looked at the adsorber capabilities of dealing with sulphur poisoning and how well the adsorber could be de-sulphurised.
This programme showed clearly the stronger and weaker points in the NOx adsorber technology for heavy duty application. From NOx conversion - BSFC penalty trade off curves it became clear that at lower loads high conversions (> 90%) with small fuel penalties (< 2.5%) were possible. However at high load the conversions were reduced (< 70%) and the fuel penalties increased (> 6%). Another conclusion is that more catalyst durability development is required. Provided this durability plus the robustness towards (de-) sulphurisation improves then the single bank NOx adsorber technology could have potential for heavy duty applications.