EXPERIMENTAL AND NUMERICAL-STUDIES ON TRANSMISSION OF GASEOUS DETONATION TO A LESS SENSITIVE MIXTURE

A phenomenon of detonation transmission from one gaseous mixture (dono r) to another of lower sensitivity (acceptor) was studied experimental ly and numerically. The objective was to study effects of a donor mixt ure length and acceptor mixture sensitivity on the possibility of deto nation transmission. Experiments were carried out in detonation tube 9 .5-12 m long and 174 mm id. Three types of donor mixtures were used in the driver: stoichiometric acetylene/air, stoichiometric hydrogen/air , and 20% of hydrogen/air. Air mixtures with 14-29.6% of hydrogen were used as accepters. Driver length varied from 0.17 to 5.6m. Detonation transmission was studied for an abrupt opening of interface between t wo mixtures. Series of 1D and 2D calculations were made to simulate th e problem numerically. Both, results of experiments and calculations r evealed a set of parameters that effect transmission process. Critical conditions were determined as minimum driver length expressed in term s of characteristic chemical reaction length scales of acceptor mixtur e. They were shown to depend on differences in reaction rates and ener gy contents of donor and acceptor mixture.