Qin Yi 1,2,3,4, Chen Xiaowei 1,5, Huang Wei 3
1. State Key Laboratory of Explosion Science and technology, Beijing University of technology, Beijing 100081
2. School of mechanical and electrical engineering, Beijing University of technology, Beijing 100081
3. Safety Engineering College of Chongqing University of science and technology, Chongqing 401331
4. Institute of general engineering, China Academy of Engineering Physics, Mianyang, Sichuan 621999
5. Frontier Interdisciplinary Research Institute of Beijing University of technology, Beijing 100081
In order to avoid the damage caused by the explosion of combustible premixed gas in the confined space, it is the key of anti explosion design and daily safety management to predict the explosion overpressure accurately. Based on the experimental data of the existing literature, the explosion overpressure model is established by using the smooth laminar flame propagation theoretical model. The instability in the process of flame propagation in a large volume confined space causes the flame front to fold and cause turbulent combustion, which leads to a large increase in the surface area of the flame front, and shows similar fractal characteristics in the process of flame propagation. According to the self similar fractal characteristics in the process of fold and turbulent flame propagation, and based on the fractal combustion theory and relevant empirical data, the prediction model of explosion overpressure considering the fold and turbulent flame propagation of combustible premixed gas explosion is further established, and compared with the experimental results. The results show that when the volume of the confined space is large and the peak pressure is estimated by using the explosion overpressure model established by the theory of fold and turbulent flame propagation, the relative errors of the experimental and theoretical calculation under the two conditions are 10.4% and 11.1%, respectively. Compared with the smooth laminar flame propagation theoretical explosion overpressure model, the errors are reduced by 72.3% and 50.6%, respectively. The theoretical model established in this paper is in good agreement with the experimental results, which can meet the needs of structural anti explosion design or daily safety management to a certain extent.
Key words: laminar flame, turbulent flame, explosion overpressure, prediction model
Quoted text: Qin Yi, Chen Xiaowei, Huang Wei. Prediction of overpressure of combustible gas explosion in confined space [J]. Explosion and impact, 2020, 40 (3): 032202. Doi: 10.11883/bzycj-2019-0175
Table 2 peak overpressure value of experiment and theoretical calculation
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