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Shock tubes are vital experimental tools that are used to study high temperature gas-phase kinetics and shock tube research accounts for most of the high temperature experimental data relevant to combustion. Several shock tube techniques are briefly discussed and references to prior more detailed reviews supplied. The use of shock tube techniques to elucidate reaction rates and mechanisms for elementary unimolecular and bimolecular reactions is discussed. Particular attention is given to studies that provide fundamental data that can be extrapolated to systems that cannot be studied in isolated experiments. In this context, experiments on the dissociation and isomerization of fuel radicals, pyrolysis of saturated cyclic and heterocyclic molecules of importance in surrogate fuels and nontraditional fuels, and the role of resonantly stabilized radicals in formation of polycyclic aromatic hydrocarbons are discussed.

A shock tube is a device in which a shock wave is normally formed by the rupture of a diaphragm, which divides a gas at high pressure from a test section containing the species of interest at a lower pressure. The shock wave brings the test gas virtually instantaneously to a known high temperature and pressure, maintains that condition for a time and then is supplanted by an expansion wave which cools the sample rapidly. During this time, the test gas can be studied by continuous sampling, for example to a time-of-flight mass spectrometer or alternatively sampled at the end of process by gas chromatography or other appropriate analytical techniques. Here, we discuss both methodologies and show with examples the benefits of both approaches.