Comparison of Three Soot Models Applied to Multi-Dimensional Diesel Combustion Simulations

Abstract

In this paper, three soot models previously proposed for diesel combustion and soot formation studies are briefly reviewed and compared. The three models are (1) two-step empirical soot model, (2) eight-step phenomenological soot model, and (3) complex-chemistry coupled phenomenological soot model. All three models have been implemented into the KIVA-3V simulation code. For comparison, a heavy-duty DI diesel engine case with fuel injection typical of standard DI diesel operating conditions was studied. Flame structures of a single diesel spray predicted using these three models were compared, and the results offer our perspective on the application of these three models to soot modeling in diesel engines.

Nine-step phenomenological diesel soot model validated over a wide range of engine conditions

“…These experimental cases cover a wide range of SOI timing and EGR. The SOI timings were varied from −20 to 5 • CA ATDC, and the EGR were supplied at three levels (i.e., 8,27, and 40%). The engine was operated at Mode 2, corresponding to 25% load and 821 rev/min.…”

“…In a recent work [7,8], three different soot modeling approaches were compared and several advantages of multi-step phenomenological (MSP) soot models highlighted. First, the MSP soot models involve only a few more steps than the two-step soot model, thus introducing almost no extra cost in computations.…”

Towards a detailed soot model for internal combustion engines

“…In [17], three empirical soot models of varying complexity implemented in KIVA are reviewed and compared.…”

Soot and NOx Modelling for Diesel Engines

“…This two-step empirical model doesn't consider detailed information on the soot formation mechanism and is independent of fuel. The simulation using this model can predict flame and soot distribution in a diesel spray in the engine; however, the flame predicted by this model disagrees with the diesel flame structure in the near nozzle region (Tao et al 2005). Therefore, detailed information of soot formation predicted is not accurate.…”