The article presents the experimental study analysis results of the methane combustion efficiency in a high-enthalpy oxygen-containing flow (HOF) inside of constant cross-section channel, finite along the length. The range of initial HOF enthalpies was considered from 350 to 700 kJ/kg. The regularities of the HOF initial enthalpy influence on the methane combustion efficiency were obtained. The values of the fuel excess coefficient under which the maximum coefficients of methane combustion completeness in the HOF are realized were determined. The data obtained indicate the realization of transitional diffusion-kinetic modes of methane combustion and make it possible to assess the factors limiting the combustion process.

The results of an experimental study of the effect of integral electrical and acoustic action on flame stabilization during combustion of a homogeneous air-methane mixture are presented. The...

The article is devoted to estimating the intensifying efficiency of methane-air ignition by adding a small amount of hydrogen and/or ethylene. It presents features of the experimental determination of the ignition delay period for fuel-air mixtures using shock installation and methods of processing empirical data. The testing of the known ignition kinetic models for methane, hydrogen, and ethylene with air was carried out. The results of test calculations were compared with those previously published, as well as original experiments. The kinetic model was chosen to provide the minimum discrepancy between the calculated and experimental data. The regularities of the effect of hydrogen and ethylene additives on the ignition dynamics of the methane-air mixture for the range of initial pressures from 1 to 8 bar at temperatures from 900 to 1100 K were obtained with the use of non-stationary numerical modeling. Methane-air mixtures with the mass fraction of additives not exceeding 10% were studied. The quantitative indicators of possible reduction in the ignition delay period of methane-air mixtures were detected.

This paper deals with the optimization criteria, mathematical model, and calculation results for the mixing of flows in a model combustion chamber with different configurations for the system of injecting the gasification products of power condenced composition. Gasification products represent a mixture of gas and condensed phases. The earlier developed data processing algorithm is improved by introducing a probabilistic approach into the trajectory estimation of the distribution of disperse phase particles in the cross sections of a model combustion chamber of small length. As a result of the performed parametric studies, some recommendations are proposed to improve the quality of mixing the gasification products with the air flow in a model combustion chamber and minimize the effect of condensed phase particles on the walls of the flow duct of a combustion chamber. The results of these studies can be used for the development of recommendations on how to provide the performability and improve the efficiency of the working process in promising power plants.

This paper presents experimental data on the ignition induction period of synthetic hydrocarbons at various temperatures and pressures obtained using a shock tube. The experimental results were used to determine the influence of the ignition induction period on the combustion efficiency of hydrocarbons in high-enthalpy flows for diffusion-kinetic regimes An integral mathematical model is presented that takes into account the influence of the kinetic factors of ignition and combustion on the efficiency of physicochemical processes in air flow. The results of calculating the combustion efficiency of synthetic hydrocarbons in flows with different parameters are given.

A method is proposed for the study of the heat resistance of samples of high-temperature composite materials via local laser heating of their surface in a supersonic flow. The performed studies allow the strategic selection of high-temperature materials based on the intensity of erosion with simultaneous laser and gasdynamic effects. The ablation rates of composite materials were experimentally determined at implemented surface temperatures of 2100–2300 K and blowing with a supersonic flow at a Mach number M = 2. The effect of the various additive materials, including carbides and oxides of Hf, Si, Ta, and Zr, on the ablation rate was studied. The data can be used as recommendations in the selection of formulations for high-temperature composite materials.