To understand the gas flow processes, 3D computational fluid dynamics (CFD) models have been developed to study the goaf gas dynamics under the influence of various mining and geological parameters including ventilation layouts, face orientation and gas emission rates.
For example, gas flow processes in a porous medium may be subject to different flow regimes within different pores; diffusion is important only within small pores for a given pore pressure.
Based on extensive studies of the mining induced overburden de-stressing, permeability distribution, and goaf gas flow processes under drainage and ventilation, a conceptual model, called annular overlying zone (AOZ) as shown in Fig. 13, was developed.
Above-boiling temperature conditions, as encountered, for example, in geothermal reservoirs and in geologic repositories for the storage of heat-producing radioactive wastes, may induce strong liquid and gas flow processes in porous subsurface environments.
The gas flow rate, process pressure, and plasma power density were 10 sccm, 4 Pa, and 0.221 W/cm2, respectively.
Results are also presented on the exclusion of oxygen and moisture from the coating area, achieved using the same gas flow isolation process.
Due to the complex gas solids flow process, it is extremely desirable that a real time monitoring and control system is used in the process in order to enable a bubbling stable fluidization and reduce the chance of defluidization due to agglomeration with high moisture contents particles.
Simulations on the behaviour of TiCl4 and NH3 process gas flows during process conditions in the RTCVD reactor chamber using Lennard Jones Potential approximation and Phoenics CVD software show that the two main gas species TiCl4 and NH3 behave very different and thus thoroughly have to be treated individually.
