Explosion development and deflagration-to-detonation transition in coal dust/air suspensions

https://doi.org/10.1016/S0082-0784(88)80261-3Get rights and content

Large-scale experiments, conducted by the CEGB, to investigate the development of propagating explosions of flowing coal dust/air suspensions in ducts have produced flame speeds and pressures up to detonation levels. These results provide perhaps the clearest evidence to date that detonations can develop in coal dust/air suspensions by way of deflagration to detonation transition (DDT).

The experimental facility comprised a 0.6m diameter instrumented test duct supplied with mixture from an air blower and coal dust feeder installation, and was equipped with appropriate ignition source devices. The tests were performed in two distinct phases:

Phase 1 comprised tests in a 30 m straight duct, and produced deflagrations with modest flame speeds and pressure rises up to little more than 1 bar.

Phase 2 involved the inclusion in the test line of an explosion chamber of volume 20 m3 and an extension of test duct length to 42m. These changes produced much-enhanced flame speeds and pressure rises which, under particularly favourable conditions of mixture composition, reached detonation values with pressures up to 81.5 bar and clear evidence of DDT.

Data are presented which illustrate the dependence of explosion strength on system geometry, ignition source, coal type and mixture parameters, and the relationship between measured values of maximum flame speed and pressure rise is compared with those derived from other related research.

References (6)

  • CybulskiW.
  • BartknechtW.
  • ShchelkinK.I. et al.
There are more references available in the full text version of this article.

Cited by (0)

View full text