Abstract
In order to study the heat transfer issue of underground coal gasification (UCG) channel, an extension model of cylindrical channel was established to study the temperature distribution law of UCG channel during the entire gasification process (dry and distillation stage, reduction stage and oxidation stage) based on the Fourier heat transfer theory and the Laplace transform method. Considering the radial extension of gasification boundary, this issue is a thermal conduction of moving boundary condition, and the unsteady thermal conduction mathematical equation under the moving coordinate system was established, and assumes that the gasification channel boundary satisfies the first kind of boundary condition in the entire gasification process, and the boundary temperature changes in a piecewise linear manner. The secondary Laplace transform and inversion method was used to solve the temperature equations of all stages, and the analytical solutions, which contains the initial temperature distribution function w1η+u2τ orw2η+u3τ, were also obtained. The values and their changing laws of temperature propagation range (t ≥ 30 °C, or Δt ≥ 10 °C) and the high-temperature distribution range (t ≥ 300 °C) were also given, and they are affected by the boundary temperature conditions and the radial extension rate of gasification channel.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call