Numerical heat transfer and thermal engineering of AdBlue (SCR) tanks for combustion engine emission reduction

In the automotive industry the selective catalytic reduction (SCR), which converts nitrogen oxides into nitrogen and water in the presence of a reducing agent, namely the so-called AdBlue urea–water solution, becomes major importance as a powerful emission reduction technique. Thermal engineering of SCR-tanks is a great challenge due to the melting and freezing behaviour of the AdBlue-fluid. In this paper, an efficient use of computational fluid dynamics and numerical heat transfer methods is presented for developing and optimising automotive SCR-tank systems. These thermal simulations include the phase change (melting and freezing), heat conduction, power generation, and natural convection effects within the liquid. The accuracy of the numerical scheme is assessed by comparisons with benchmark cases and experimental data. Typical industrial application examples are presented.