ترغب بنشر مسار تعليمي؟ اضغط هنا

Kinetic modelling of a surrogate diesel fuel applied to 3D auto-ignition in HCCI engines

465   0   0.0 ( 0 )
 نشر من قبل Denise Hagnier
 تاريخ النشر 2007
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Roda Bounaceur




اسأل ChatGPT حول البحث

The prediction of auto-ignition delay times in HCCI engines has risen interest on detailed chemical models. This paper described a validated kinetic mechanism for the oxidation of a model Diesel fuel (n-decane and α-methylnaphthalene). The 3D model for the description of low and high temperature auto-ignition in engines is presented. The behavior of the model fuel is compared with that of n-heptane. Simulations show that the 3D model coupled with the kinetic mechanism can reproduce experimental HCCI and Diesel engine results and that the correct modeling of auto-ignition in the cool flame region is essential in HCCI conditions.



قيم البحث

اقرأ أيضاً

68 - Bagher Abareshi 2017
Auto-ignition process of stoichiometric mixture of methane-air is investigated using detailed chemical kinetics in a single-zone combustion chamber. Effect of initial temperature on start of combustion (SOC). The Arrhenius expression for the specific reaction rate are calculated and auto-ignition was evaluated based on the species fractions and sensitivity analysis. Our results suggest that the SOC is directly related to initial temperature and the auto-ignition will not occur if the initial temperature low enough.
The Minimum Ignition Energy (MIE) of an initially Gaussian temperature profile is found both by Direct Numerical Simulations (DNS) and from a new novel model. The model is based on solving the heat diffusion equation in zero dimensions for a Gaussian velocity distribution. The chemistry is taken into account through the ignition delay time, which is required as input to the model. The model results reproduce the DNS results very well for the Hydrogen mixture investigated. Furthermore, the effect of ignition source dimensionality is explored, and it is shown that for compact ignition kernels there is a strong effect on dimensionality. Here, three, two and one dimensional ignition sources represent a spherical kernel, a long spark and an ignition sheet, respectively.
This paper proposes a methodology to estimate stress in the subsurface by a hybrid method combining finite element modeling and neural networks. This methodology exploits the idea of obtaining a multi-frequency solution in the numerical modeling of s ystems whose behavior involves a wide span of length scales. One low-frequency solution is obtained via inexpensive finite element modeling at a coarse scale. The second solution provides the fine-grained details introduced by the heterogeneity of the free parameters at the fine scale. This high-frequency solution is estimated via neural networks -trained with partial solutions obtained in high-resolution finite-element models. When the coarse finite element solutions are combined with the neural network estimates, the results are within a 2% error of the results that would be computed with high-resolution finite element models. This paper discusses the benefits and drawbacks of the method and illustrates their applicability via a worked example.
A one dimensional (1-D), isothermal model for a direct methanol fuel cell (DMFC) is presented. This model accounts for the kinetics of the multi-step methanol oxidation reaction at the anode. Diffusion and crossover of methanol are modeled and the mi xed potential of the oxygen cathode due to methanol crossover is included. Kinetic and diffusional parameters are estimated by comparing the model to data from a 25 cm2 DMFC. This semi-analytical model can be solved rapidly so that it is suitable for inclusion in real-time system level DMFC simulations.
The document describes a numerical algorithm to simulate plasmas and fluids in the 3 dimensional space by the Euler method, in which the spatial meshes are fixed to the space. The plasmas and fluids move through the spacial Euler mesh boundary. The E uler method can represent a large deformation of the plasmas and fluids. On the other hand, when the plasmas or fluids are compressed to a high density, the spatial resolution should be ensured to describe the density change precisely. The present 3D Euler code is developed to simulate a nuclear fusion fuel ignition and burning. Therefore, the 3D Euler code includes the DT fuel reactions, the alpha particle diffusion, the alpha particle deposition to heat the DT fuel and the DT fuel depletion by the DT reactions, as well as the thermal energy diffusion based on the three-temperature compressible fluid model.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا