Numerical simulation of ignition of particles of a coal–water fuel

Mathematical modeling of heat transfer in production premises heated by gas infrared emitters

“…Numerical studies were carried out for free-convective flows corresponding to the turbulent regime for two Grashof numbers: Gr = 4 10 12 and Gr = 10 10 The analysis of thermal regimes in the quite typical region under consideration can be carried out both with respect to the distributed characteristics of the process (inhomogeneous in real practice and nonstationary temperature fields) and by the averaged ones (the temperature averages over the region at fixed instants of time). In the first case, the temperature gradients can be estimated and the maximum or minimum air temperature zones identified.…”

“…An analysis of the ranges of changes in the main characteristics and parameters of the processes under consideration, as well as the typical sizes of the regions in which GIE is possible, showed that the Gr numbers in real conditions exceed 10 10 . That is, the regimes of thermogravitational convection under the conditions under consideration are turbulent.…”

“…To solve the system of difference analogs of the initial nonlinear partial differential equations with nonlinear boundary conditions, the method and algorithm developed [3][4][5] for solving problems of thermogravitational convection in closed regions with local energy sources were used. To substantiate the reliability of the results of numerical modeling, the conservativeness of the difference scheme was estimated by a technique developed for solving nonlinear heat conduction problems [9] and developed for ignition of water-coal fuels under conditions of intense local injection of fumes into the region filled with an oxidizer [10,11].…”

Initiation of Ignition of Highly Fuel Particles in The Flow of High Temperature Medium

“…The last is, most likely, due to inadequate basic aspects conceived of the theory of ignition of such fuels. Numerical methods [6][7][8] allow to make calculations (even with full flowing together of the complex physic-chemical processes) thermal preparation and ignition of particles of CWF. However, such techniques are difficult to apply when designing combustion equipment of boiler units.…”

Ignition of Water Coal Particles Coated with a Waterfilm in the Stream of High-Temperature Environment

“…Current models [11][12][13][14][15][16][17][18][19] of ignition and combustion of coal-water fuel droplets are not considered from the point of view the possibility of the formation of particles WCF whose surface is covered with a water film. As the experiments [20] have shown, the probability of such a configuration is very high (P ≥ 50%).…”