The Influence of Turbulent Mixing on Deflagration to Detonation Transition (original) (raw)
In the current study, the influence of turbulent mixing on Deflagration to Detonation Transition (DDT) is investigated, using a state-of-the-art Large Eddy Simulation (LES) strategy, for conditions which correspond to recent experiments [1–3]. This investigation follows the procedure of Radulescu and Maxwell [4] by considering the re-ignition of fully quenched detonations, following the detonation interaction with a porous medium, as shown in Figure 1. This type of DDT has also been examined experimentally for detonation interactions with perforated plates [5], or a series of obstacles, or blockages [6,7]. Currently, the quenching process of detonations is well understood. As a detonation wave diffracts around an object, the sudden change in area causes volumetric expansion of the gas behind the leading shock wave. Eventually, the detonation can become quenched when local cooling due to this expansion overcomes local heating due to chemical reactions [8–10]. The result is a de-coupl...
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