The paper presents recent findings in quantitative evaluation of turbulence generated during venting of gaseous deflagrations in empty enclosures without initial turbulence. A correlation dependence of venting generated turbulence is presented and discussed. The scale of enclosure and the Bradley number are shown to be the main parameters influencing the turbulence generated during venting. This correlation is a part of the innovative vent sizing technology that is based on two correlations, which are valid for various combustible mixtures and enclosures of arbitrary volume and strength. The conservative form of the universal correlation for vented gaseous deflagrations is presented for the first time. The result of a comparison between the suggested conservative vent sizing formulas, experimental data and predictions by the empirical vent sizing technique of NFPA 68 standard (Edition 1998) is given. The influence of turbulence generated during venting on vent sizing of enclosures with inertial vent covers is analysed and equation for scaling of upper limit for vent cover inertia is suggested. The upper limits for vent cover inertia are estimated for enclosures of different volume from 0.1 to 1000 m~3, which can withstand the same maximum overpressure of 30 kPa and have the same vent cover release overpressure of 3 kPa. Results have demonstrated that inertial vent covers have 100% "efficiency", if inertia is below an upper limit calculated by the suggested equation, even the absolute value of inertia is much higher than the level that has been accepted so far.
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