CFD simulation and experimental study on the flow field and typical energetic dust dispersion in the 5 L column vessel

The explosion of energetic dust is more hazardous than general industrial dust, but there was a dearth of suitable equipment for measuring the explosion characteristics of energetic dust. At present, a 5 L column vessel can be used to measure the explosion characteristics of energetic dust has been created. This study examined the internal flow field and dispersion pattens of RDX dust with different particle sizes within the 5L vessel by combining CFD simulation and experiments. The results demonstrated that the flow field underwent a transformation following the introduction of RDX dust, accompanied by a notable decline in turbulence level and velocity within the vessel, and the comparison of simulation and experimental results showed that the valve weakened the airflow. The large-sized (Class-II) dust showed significant settling and more independent motion trajectory, whereas the small-sized (Class-V) dust formed a dust column in the central line of the vessel and showed better suspension, but the flow field exhibited a lack of symmetry. The optimal ignition delay time was 70 ms, and in the 70 ± 10 ms interval, the distribution of Class-II dust was more uniform. Compared with the existing 20 L spherical vessel, the 5 L vessel exhibited a markedly lower but more uniform turbulence level, and the dust distribution was significantly improved, meanwhile solved the problems of dust accumulation in the pipeline and particle size change. This study provides an important reference for the further research of 5 L column vessel and proves that it can achieve higher safety and accuracy in energetic dust explosion experiment.