Theoretical evaluation of explosion index for wood dust explosion
HU Taoping;YU Zi;GUO Lu;XU Changyan;College of Science,Nanjing Forestry University;College of Materials Science and Engineering,Nanjing Forestry University;
In the existing theoretical model of wood dust combustion and explosion parameters,the theoretical calculation only roughly simulated the evolution trend of explosion pressure over time,and there was a large deviation between the theoretical calculation result and the experimental result,which included the maximum explosion pressure and the increase rate of pressure. Based on the kinetics of combustion chemistry,the theory of thermodynamics and the theory of gas molecular dynamics,the dynamical theoretical model of wood dust explosion was proposed. According to the experimental conditions,the newly developed model was used to theoretically calculate the maximum explosion pressure and the pressure increase rate. The results were compared with the theoretical calculation results by using the existing model under different wood dust concentrations and different wood dust sizes. The comparison results indicated that the results calculated using the newly developed model were closer to the experimental results. The average deviations of the maximum explosion pressure and the maximum increase rate of pressure between this calculation and the experimental data were lower than 9%. In the case of different wood dust concentrations and different wood dust sizes,using the same experimental data,the maximum explosion pressure,the maximum increase rate of pressure and the explosion index of wood dust explosion were also calculated theoretically. Compared with the experimental measurement data,the newmodel was better than that of the existing theoretical model. In addition,this newmodel could be used to calculate the curve of the maximum increase rate of pressure with the continuous change of wood dust concentration. The results showed that the maximum pressure increased firstly and then decreased with the increase of wood dust concentration, and the maximum value appeared at the intermediate wood dust concentration. The maximum value of the explosion index calculated was 14. 57 MPa·m/s, and the corresponding wood dust concentration was 845 g/m3. The concentration range of wood dust with an explosion index of over 10 MPa·m/s was330-1 945 g/m3. In this interval,the explosion indexes of different wood dust concentrations can be accurately confirmed by this newtheoretical model. In conclusion,the newly developed model had high consistency with experimental data,which can accurately predict the possible explosion index of wood dust explosion.
【Fund】： 国家重点研发计划(2016YFD0600703-1);; 江苏省研究生科研与实践创新计划项目(KYCX17_0841)
【CateGory Index】： O643.221
【CateGory Index】： O643.221