A large eddy simulation (LES) model was developed to simulate the combustion process in a spark-assisted homogeneous charge compression ignition (SACI) engine. First, an ignition and flame propagation model based on a reaction progress variable is presented. The reaction progress variable is defined based on the normalized cumulative heat release. Transport equation for the progress variable is...

We derive analytical expressions for the propagation speed of downward combustion fronts of thin solid fuels with a background flow initially at rest. The classical combustion model for thin solid fuels that consists of five coupled reaction-convection-diffusion equations is here reduced into a single equation with the gas temperature as the single variable. For doing so we apply a two-zone com...

Exhausts of airship fabric bag in the stratosphere such as hydrogen which can be used for fuels by using catalytic combustion method. This can save the extra fuels used in the power system. Pd/γAl2O3 catalyst was prepared in this work by impregnation method and the H2 catalytic combustion reaction kinetic was investigated between the pressure of 3.6 kPa and 101.3 kPa. The effects of temperature...

Catalytic combustion is a promising technique for producing thermal energy in MEMS(Micro Electro-Mechanical Systems) scale electrical power generators. To examine the feasibility and possible benefits of catalytic combustion in MEMS-scale channels, catalytic reactions in small diameter (1 mm) flow reactor tubes at low Reynolds numbers are simulated by using the commercial fluid dynamics code FL...

A new low-temperature method to produce (InxGa1−x)2O3 (x 4 0.1, 0.2, and 0.3) powders with high purity, high chemical homogeneity and improved crystallinity in the as-synthesized state has been developed. This procedure produced finely divided powders through an exothermic reaction between the precursors. The process starts with aqueous solutions of In(NO3)3 and Ga(NO3)3 as the precursors and h...

In order to get a methane catalytic combustion micro-sensor, two different catalytic systems used in traditional methane catalytic combustion sensors were fabricated into a mesoporous structure and their catalytic activities were investigated. In comparison, the Rh2O3-Al2O3 system can form more a uniform mesoporous structure and has a much higher specific surface area. Even more importantly, it...

Hazardous organic wastes from industrial, military, and commercial activities represent one of the greatest challenges to human beings. Advanced oxidation processes (AOPs) are alternatives to the degradation of those organic wastes. However, the knowledge about the exact mechanisms of AOPs is still incomplete. Here we report a phenomenon in the AOPs: induced effects, which is a common property ...

In this paper the travelling wave solutions in the adiabatic model with two-step chain branching reaction mechanism are investigated both numerically and analytically in the limit of equal diffusivity of reactant, radicals and heat. The properties of these solutions and their stability are investigated in detail. The behaviour of combustion waves are demonstrated to have similarities with the p...

Ammonium glycolate combustion was used to synthesize SrZr0.95Y0.05O3−x powders. Soluble metal-glycolate complexes, detected by infrared spectroscopy, were formed with Y+3 and Zr+4, which maintain atomic level mixing of metal cations with glycolic acid. Sr+2/glycolic acid mixtures did not form glycolate complexes. Temperature-programmed reaction studies showed that only precursor solutions with ...

0021-9991/$ see front matter 2012 Elsevier Inc http://dx.doi.org/10.1016/j.jcp.2012.06.029 ⇑ Corresponding author. E-mail address: [email protected] (M. Ihme). Many combustion models that are based on the flamelet paradigm employ a reaction progress variable. While such a progress variable is well defined for one-step reaction kinetics, this is typically not the case for complex chemical mechanis...