Mathematical modelling of sparkplug ignition of a coal-dust monodisperse suspension in a methane-air mixture

The paper provides the numerical simulation of a coal-dust monodisperse suspension sparkplug ignition in a methane-air mixture. The methane-air mixture is not stoichiometric. The aim of the research is a design-theoretical determination of the minimum ignition energy of coal-dust-methane-air mixture (CDMAM) depending on the methane volume fraction. Simulation has shown that the increase of the methane volume fraction leads to the decrease of the CDMAM minimum ignition energy, and with the expansion of coal particles the minimum ignition energy rises

Effect of coal dust on the air-methane mixture combustion in the Swiss-roll burner

The 2-D numerical model has been developed to simulate the combustion of lean coal-methane-air mixture in “Swiss-roll” burner and investigate the effect of coal particles content and mixture feed rate on the stable burner operation. Five homogeneous and three heterogeneous chemical reactions are considered. The Eulerian model for gas phase and the discrete particle model (Lagrangian) for particle phase taking into account the radiation are used in this study. Simulations are performed for the two turns “Swiss roll” burner with heat insulated outer wall, channel width of 6 mm and inner wall thickness of 2 mm. It is shown that the presence of coal particles in a lean methane-air mixture expands the range of stable operation of the "Swiss-roll" burner. It is found that an increase in the content of coal particles reduces the combustion time of the particles by in-creasing the combustion temperature, changes the shape of the reaction zone, and shifts it to the burner inlet

Numerical investigation on burning stability of the coal-dust methane-air mixture in a recuperative burner

The paper is devoted to numerical investigation on combustion singularities of the bi-dispersed coal-dust methane-air mixture in a slot recuperative burner. The aim of the research is to determine the stable combustion conditions of the methane-air mixture depending on the fuel flow rate at the inlet of the burner and on the parameters of the mixture (the particle size and the mass concentration of the coal particles, the percentage composition of inert particles and the methane volume content). The problem was solved by finite difference method. The regimes of stable combustion for the coal-dust methane-air mixture depending on the fuel content and the fuel flow rate at the inlet of the burner the have been defined

Investigation of the combustion stability of methane-air mixture in recuperative burners of different geometries

The results of numerical investigations of 5.5% methane-air combustion stability in heat recuperative burners (counter flow burner, U-shape burner and Swiss-roll burner) are presented in this paper. The investigation is carried out with the use of commercial CFD package Ansys-Fluent. The boundaries of combustion stability of 5.5% methane-air mixture depending on the gas flow rate at the inlet of the burners are determined

Thermal interaction of biological tissue with nanoparticles heated by laser radiation

We explore the problem of thermal interaction of nanoparticles heated by laser radiation with a biological tissue after particle flow entering the cell. The solution of the model equations is obtained numerically under the following assumptions: a single particle is located in a neighborhood exceeding the particle size; the environment surrounding the particle is water with the conventional thermal characteristics. The model equations are deduced from the particle and the environment energy conditions taking into account the heat transfer in the particle and in its environment by conduction. We also assume that at the boundary between the particle and the surrounding water the perfect thermal contact takes place

Influence of the medical and social characteristics of patients on the assessment of the effectiveness of treatment

The article examines the influence of the characteristics of the medical and social characteristics of surgical patients on their assessment of the effectiveness of treatment in a hospital. The study was conducted on the basis of Mariinskaya City Hospital by random sampling by questioning 100 patients undergoing treatment at surgical departments. It has been established that patients with surgical pathology undergoing inpatient treatment represent a special social group that has conditions and lifestyle characteristics that have a positive impact on their evaluation of the treatment. Patients highly appreciate the effectiveness of treatment in surgical departments

Adsorptive Voltammetry of 4-chlordehydromethyltestosterone

The article presents the results of the study of the electrochemical behavior of the anabolic steroid 4-chlordehydromethyltestosterone. The studies detected operating conditions for the voltammetric determination of anabolic glassy carbon electrode. The influence of such factors as pH, supporting electrolyte, the electrolysis and adsorption component on the analytical signal of the analyte was studied. The algorithm of sample preparation is presented and conditions for the quantitative determination of the active ingredient of the drug “Turinabol” by voltammetry is proposed. The evaluation of the proposed method accuracy was conducted

Digital Technologies in Art: on the Example of the 16th Istanbul Biennale

The article is devoted to the use of digital technology in the framework of the 16th Istanbul Biennale. It explores specific examples of digital accompaniment of works.Статья посвящена применению цифровых технологий в рамках 16‑й Стамбульской биеннале. Рассматриваются конкретные примеры цифрового сопровождения произведений