Evaluation of accident scenarios including flame acceleration and deflagration-to-detonation transition (DDT) in chemical plant piping systems increases the need for an efficient numerical simulation tool capable of dealing with this phenomenon. In this work, a hybrid pressure-density-based solver including deflagrative flame propagation as well as detonation propagation is presented. The initial incompressible acceleration stage is covered by the pressure-based solver until the flame velocity reaches the fast flame regime and transition to the density-based solver is done. The deflagration source term is formulated in terms of a turbulent flame speed closure model incorporating various physical effects crucial for flame acceleration at low turbulence conditions (Katzy and Sattelmayer, 2018). Modelling of the detonation source term is based on a quadratic heat release function (Hasslberger, 2017). The presented numerical approach is validated in terms of DDT locations and pressure data from Schildberg (2015) as well as recently completed flame tip position measurements. For this purpose, H₂/O₂/N₂ mixtures ranging from 25.6 vol-% H₂ to 29.56 vol-% H₂ in two different pipe geometries are considered. The focus of the current work is on predicting the DDT location correctly and good agreement is observed for the investigated cases.

对化工厂管道系统中包括火焰加速和爆燃-爆轰过渡（DDT）在内的事故场景的评估增加了对能够处理这种现象的有效数值模拟工具的需求。在这项工作中，提出了一种基于混合压力密度的求解器，包括爆燃性火焰传播和爆轰传播。初始不可压缩的加速阶段由基于压力的求解器覆盖，直到火焰速度达到快速火焰状态并完成向基于密度的求解器的过渡为止。爆燃源术语是根据湍流火焰速度闭合模型制定的，该模型包含了对低湍流条件下火焰加速至关重要的各种物理效应（Katzy和Sattelmayer，2018年）。爆震源项的建模基于二次放热函数（Hasslberger，2017）。根据Schildberg（2015）的DDT位置和压力​​数据以及最近完成的火焰尖端位置测量，对本文提出的数值方法进行了验证。为此，H在两种不同的管道几何形状中，考虑了₂ / O ₂ / N ₂混合物，其混合物的H ₂为25.6体积％H ₂至29.56体积％H ₂。当前工作的重点是正确预测滴滴涕的位置，并在调查的案例中观察到良好的一致性。