Prediction of Ignition Delay Time of Premixed Gas Using a Micro Flow Reactor

Abstract

To examine new fuel's ignition delay time, a simpler experimental method other than a shock tube or a rapid compression machine is required. In this study, a new method to estimate ignition delay time combining a micro flow reactor and the Livengood-Wu integral is proposed. Using a micro flow reactor, which has a steady temperature distribution by an external heat source, the steady ignition point for premixed gas under constant pressure is obtained. Then, the temperature history that the premixed gas had experienced before it ignites can be calculated. Based on the Livengood-Wu integral and the temperature history, the coefficient and the activation energy for the Arrhenius type ignition delay model was obtained. Finally, the ignition delay time for the lean methane-air premixed gas is predicted using ignition point and temperature history. However, the predictions were quite different from other researches because the actual temperature history might be changed from the temperature history obtained before ignition for normal flame with heat release from its combustion. But for weak flame with less heat release, more accurate value was obtained.