Deisy Chaves^1,5,*, Maria Trujillo¹, Edward Garcia², Juan Barraza², Edward Lester³, Maribel Barajas⁴, Billy Rodriguez⁴, Manuel Romero⁴, Laura Fernández-Robles⁵

Intelligent Automation & Soft Computing, Vol.26, No.3, pp. 397-405, 2020, DOI:10.32604/iasc.2020.013916

Abstract Precise automated determination of char morphologies formed by coal during combustion can lead to more efficient industrial control systems for coal combustion. Commonly, char particles are manually classified following the ICCP decision tree which considers four morphological features. One of these features is unfused material, and this class of material not characteristic of Colombian coals. In this paper, we propose new machine learning algorithms to classify the char particles in an image based system. Our hypothesis is that supervised classification methods can outperform the 4 ‘class’ ICCP criteria. In this paper we evaluate several morphological features and specifically assess the… More >

Jong Seong Chae¹, Seok Wan Kim², Tae In Ohm^1,*

Journal of Renewable Materials, Vol.8, No.7, pp. 789-799, 2020, DOI:10.32604/jrm.2020.010023

Abstract In the production (as co-fuel or alone) of solid refuse fuel (SRF), knowledge about the characteristics of the raw materials is required for an ecofriendly and effective combustion process. SRFs are commonly produced by drying combustible waste and removing incombustible matter, resulting in a higher combustibility as compared to the original waste. However, the characteristics of SRFs may highly vary depending on where and from which materials they were produced. Thus, we investigated the characteristics of various SRFs using thermogravimetric analysis (TGA). As a TGA sample is commonly small, on the scale of milligrams, and, unlike homogeneous fuels, SRFs are… More >

Yongkang Zheng^1,2,*, Chao Yan¹

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.3, pp. 637-650, 2020, DOI:10.32604/fdmp.2020.09694

Abstract The flow field inside the combustor of a scramjet is highly complicated and the related turbulent Prandtl and Schmidt numbers have a significant impact on the effective numerical prediction of such dynamics. As in many cases researchers set these parameters on the basis of purely empirical laws, assessing their impact (via parametric numerical simulations) is a subject of great importance. In the present work, in particular, two test cases with different characteristics are selected for further evaluation of the role played by these non-dimensional numbers: Burrows-Kurkov case and DLR case. The numerical results indicate that these parameters influence ignition location.… More >

Lei Zhang¹, Haiyan Wang^1,*, Junpeng Zhang¹, Zhi Wang², Zuohui Xu¹, Xinyu Gao¹

Journal of Renewable Materials, Vol.8, No.3, pp. 219-237, 2020, DOI:10.32604/jrm.2020.09096

Abstract The effects of the number of layers, the arrangement of carbon fiber (CF) tow and the epoxy resin (ER) matrix on the fire performance of carbon fiber/epoxy composites (CFEC) were studied by a variety of experimental methods. The results show that the number of layers of CF tow has influence on the combustion characteristics and fire propagation of the composites. The arrangement of CF tow has influence on flame propagation rate and high temperature mechanicalproperties. The mechanism of the influence of the number of layers of CF tow on the composite is mainly due to the different thermal capacity of… More >

Zaiguo Fu^{1, *}, Huanhuan Gao¹, Zhuoxiong Zeng¹, Jiang Liu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.3, pp. 805-830, 2020, DOI:10.32604/cmes.2020.08825

Abstract In order to comprehensively evaluate the flow and heat transfer performance of a large-size annular combustion chamber of a heavy-duty gas turbine, we carried out numerical computation and analyses on the velocity, temperature and pressure fields in the chamber with double swirlers. The mathematical model of the coupling combustion, gas flow, and heat transfer process was established. The influences of the inlet swirling strength, fuel-air ratio and temperature of the premixed gas on the multi-field characteristics and synergy were investigated on the basis of field synergy theory. The results showed that the central recirculation zone induced by the inlet swirling… More >

Jianjun Liang¹, Zhe Song², Peili Zhang^{1, *}

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.4, pp. 445-458, 2019, DOI:10.32604/fdmp.2019.07951

Abstract In order to investigate the burning characteristics of a 0# diesel and 3# jet fuel, a small-scale experimental bench mainly composed of a cone calorimeter was arranged. The heat release and burning rates were investigated changing the external irradiance in order to clarify the triadic relationship among these quantities. The effective heat of combustion of 0# diesel and 3# jet fuel were 38.89 MJ/kg and 43.15 MJ/kg, respectively, with the corresponding combustion efficiencies being 96.78% and 99.60% (the effective peak heat of combustion being 1.665 times the mean value for both types of fuel). According to our experimental results, the… More >

W. A. El-Askary^1,2, S. A. Wilson², A. Hegab²

CMES-Computer Modeling in Engineering & Sciences, Vol.76, No.3&4, pp. 235-266, 2011, DOI:10.3970/cmes.2011.076.235

Abstract In the present work, a complete simulation of reactive flow in the combustion chamber of a rocket motor equipped with convergent-divergent nozzle has been introduced. The model describes the combustion process inside the combustion chamber considering a steady premixed reactant gas injected through side porous walls of the combustion chamber. The products flow through a convergent-divergent nozzle with adiabatic impermeable walls. The reactants are treated as two-dimensional, multi-components, turbulent compressible flow. The local properties of the mixture are calculated and updated during the solution process. At the boundary of the combustion chamber, a constant mass flux and predefined properties are… More >

SouadMorsli^1,*, Amina Sabeur¹, Mohammed El Ganaoui²

FDMP-Fluid Dynamics & Materials Processing, Vol.11, No.4, pp. 342-353, 2015, DOI:10.3970/fdmp.2015.011.342

Abstract The aim of this work is the numerical simulation of the combustion of hydrogen with air in a burner and the numerical solution of local entropy generation rate in the combustion chamber. The effects of equivalence ratio φ and oxygen percentage γ on combustion and entropy generation rates are studied for different φ(ranging from 0 to 1.0) and γ values (ranging from 10 to 30%). The predictions show that the increase of φ (or the decrease of λ ) reduces notably the reaction rate levels. The equations of continuity, of energy and momentum are solved by volume finite using commercial… More >

R. Prosser¹

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.4, pp. 411-424, 2009, DOI:10.3970/fdmp.2009.005.411

Abstract A novel wavelet-based method for the simulation of reacting flows on adaptive meshes is presented. The method is based on a subtraction algorithm, wherein the wavelet coefficients are calculated from the low resolution up (as opposed to the standard top-down approach). The advantage of this new method is that it allows the calculation of wavelet coefficients on sparse grids, and thus lends itself more readily to adaptive computational meshes than does the traditional wavelet algorithm. The approach is used to simulate a one-dimensional laminar pre-mixed flame with different Lewis numbers. The computational grid is adapted via the removal of grid… More >