Detonation of Hydrogen/Hydrocarbon Blended Fuels.

An experimental study of detonation was carried out for mixtures of blended fuels (H2/CH4 or H2/C3H8) and air. The detonation tube length is 7m and its inner diameter is 10mm. Fast deflagration and detonation speeds were measured by means of photodiodes, which are fitted with the tube by a special technique and detect light emitted from the reaction zone. The effects of mixing ratio of fuels on the behavior of deflagration to detonation, detonation speed and detonability limits were investigated. There exists a deflagration speed at the exit of the spiral that establishes detonation, and a reproducible pulsating deflagration speed can be seen near the limit of detonation. Detonation velocity increases monotonically with equivalence ratio or the ratio of hydrogen in blended fuels.