NFPA 68 (2013) provides simple calculation methods for sizing vents for combustible dust deflagrations. These methods have limited applicability to process operations. For systems outside of the applicability limits of NFPA 68, Murphy and Melhem presented in 2016 a methodology using a burn rate model for deflagration vent sizing. It involved estimating a reference laminar burning velocity and then using this velocity to simulate behavior at different operating conditions. The paper introduced the methodology and derived a laminar burning velocity for Niacin from measurements in an explosion severity test in a 20-liter sphere. In this present work, this methodology is applied to simulate a full-scale vessel (8m)3 under both unvented and vented conditions. The results show excellent agreement with the measured values. For the vented tests, the predicted Pmax and dP/dtmac were within the experimental error of the explosion severity tests used in the analysis. For the vented tests, the value of Pred was within the range of published measured values. Laminar burning velocity is a fundamental parameter of the dust. According to Eckhoff (1997), the laminar rate at which a laminar combustion wave or reaction zone propagates relative to the unburnt gas is called the fundamental or laminar burning velocity.
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