Abstract Emission measurements from unsteady combustion systems such as Pulse Detonation Combustion (PDC) are challenging due to the inherently large variations in pressure, temperature, composition, and flow velocity of exhaust gas. Comparison experimental data is additionally complicated by differences operating conditions gas sampling setup between different facilities. Qualitative considera...

An experimental investigation into the detailed mixing, combustion and ignition processes occurring in a flow field under the influence of resonant acoustic perturbations has been performed. These acoustic perturbations were created by a pulse combustor of the "Helmholtz" type. Cycle-resolved ensemble-averaged measurements of the velocity field, combined with instantaneous images of chemilumine...

We describe transient spectroscopic measurements with a current-switched semiconductor diode laser. Following a fast pulse modulation in the injection current of the diode laser, the diode laser frequency is switched by a few hundred MHz and, then, is scanned over 10 GHz range in a short-time evolution (<0.5 μs). Free-induction decay based on the frequency switching and transient absorption spe...

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