关键词: 粉尘爆炸, 泄放设计, 静态动作压力, 最大泄爆压力, 泄放关系式

Abstract: The reliability of dust explosion venting standards is of great importance to explosion protection. Dust explosion venting experiments with four venting diameters under elevated static activation overpressures ranging from 0.12 to 0.6MPa were performed in the 20-liter chamber. The lycopodium dusts with a median diameter of 70μm were adopted. The experimental results were compared with the predictive values calculated by NFPA 68 and EN 14491. The results indicated that NFPA 68 results tend to be conservative for small venting diameters and dangerous for larger venting diameters. It was found that the prediction results of NFPA 68 correlation have a good accuracy and are stable under elevated static activation overpressures. However， the prediction results of EN 14491 are inaccurate and unstable， which tend to be very conservative. The huge divergence between NFPA 68 and EN 14491 results under elevated static overpressures was analyzed based on the correlations of the empirical functions proposed by the standards.

Key words: dust explosion, venting design, static activation overpressure, maximum reduced overpressure, venting correlation