Numerical simulation of “temperature-chemistry” coupling process of oxidation and heat storage of residual coal in goaf

Abstract

Under certain conditions, the residual coal in goaf will be heated up by oxidation and heat accumulation. Taking the chemical reaction field and heat transfer field in the process of coal oxidation as the research objects, the coupling model of chemical reaction field and heat transfer field is proposed, and the control equations have been established; with parameters sweeping (heat storage coefficient η=10%, 20%, 50%, 100%), the change characteristics of chemical reaction rate and coal temperature over time and the change characteristics between chemical reaction rate and coal temperature in the process of coal oxidation heat storage in goaf under different heat dissipation conditions are revealed. The results show that the oxygen consumption rate changes in the form of negative exponential, and the coal temperature successively goes through the stages of slow rising and fast rising, which is consistent with the previous research results by relevant scholars; the chemical reaction field and heat transfer field show a positive synergistic effect in the process of coal oxidation.

Keywords

• oxidation and heat storage
• residual coal of goaf
• oxidation dynamics
• multi-physics coupling
• numerical simulation