Effect of ignition position on the run-up distance to DDT for hydrogen–air explosions
| Autor: | Detlef Arndt, Rainer Grätz, Swen Scheider, Robert Blanchard |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
Deflagration to detonation transition
Shock wave Hydrogen Chemistry General Chemical Engineering Environmental engineering Detonation Energy Engineering and Power Technology chemistry.chemical_element Mechanics Management Science and Operations Research Industrial and Manufacturing Engineering law.invention Ignition system Acceleration Control and Systems Engineering Position (vector) law Tube (fluid conveyance) Safety Risk Reliability and Quality Food Science |
| Zdroj: | Journal of Loss Prevention in the Process Industries. 24:194-199 |
| ISSN: | 0950-4230 |
| DOI: | 10.1016/j.jlp.2010.12.007 |
| Popis: | The method described in this paper enabled reliable and accurate positioning of an overdriven detonation by calculation of shock wave velocities (detonation and retonation) for hydrogen explosions in a closed 18 m long horizontal DN150 pipe. This enabled an empirical correlation between the ignition position and the run-up distance to DDT to be determined. It was shown that the initial ability of the flame to expand unobstructed and the piston-like effect of burnt gas expanding against the closed end of the tube contributed to initial flame acceleration and hence were able to affect the run-up distance to overdriven detonation. Flame speeds and rates of initial pressure rise were also used to explain how these two competing effects were able to produce a minimum in the run-up distance to DDT. The shortest run-up distance to DDT, relative to the ignition position, for this pipe and gas configuration was found when the ignition position was placed 5.6 pipe diameters (or 0.9 m) from the closed pipe end. The shortest run-up distance to DDT relative to the end of the pipe was recorded when the ignition source was placed 4.4 pipe diameters or 0.7 m from the pipe end. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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