Simulation of continuously regenerating trap with catalyzed DPF

Model-Based Temperature Sensor Fault Detection and Fault-Tolerant Control of Urea-Selective Catalyst Reduction Control Systems

“…(2) The operating conditions fluctuate drastically during certain periods of time, which makes it difficult to predict the corresponding NH 3 and NO x emissions accurately. …”

“…Because of the high air-fuel ratio and heterogeneous combustion of air-fuel mixture in the diesel cylinder, NO x and PM levels are relatively higher than those in the gasoline engine exhaust [1][2][3][4][5]. Selective catalyst reduction (SCR) systems have been extensively investigated for the removal of NO x [6], where an aqueous urea solution is injected into the upstream tailpipe of the SCR catalyst to be decomposed into NH 3 and then restored on a catalyst surface for reaction with NO x in the exhaust gas, generating nitrogen (N 2 ) and water vapor as the main products. Obviously, the urea dosing is a significant control object in the whole system; its excess injection will lead to high urea consumption and undesirable -NH 3 slip, which is also regarded as a pollutant, while on the other hand, it is entirely possible that NO x emissions will exceed the regulation limit if the urea is underdosed [7].…”

Numerical Simulation on Flow Dynamics and Pressure Variation in Porous Ceramic Filter

“…Nevertheless, by the commercial software or in-house CFD code based on the Navier-Stokes equations, it is very challenging and computationally intensive to conduct the flow simulation, because we need to consider the complex geometry of the filter substrate and internal pores [18]. Thus, for the simulation in the porous filter with particle deposition, we have adopted a lattice Boltzmann method (LBM) [13,14,16,[19][20][21][22][23].…”

“…It is well known that the numerical approach for boundary conditions in the LBM are easy, which would be suitable for the fluid simulation in porous media [24]. Previously, we have conducted the soot deposition and oxidation to simulate the particle trap and filter regeneration by LBM [13,14,16,[19][20][21][22][23]. In this study, focusing on the filter substrate structure, we tested three materials, Al 2 TiO 5 , SiC, and cordierite, in the numerical simulation.…”

“…In this study, focusing on the filter substrate structure, we tested three materials, Al 2 TiO 5 , SiC, and cordierite, in the numerical simulation. To consider the fluid dynamics in the real product, we applied X-ray CT scanning for the filter inner structure [13,14,16,21,22]. We chose five samples (see Table 1) to set the porosities such as the pore size systematically.…”