Development of Explosion Suppression System Requirements for Shipboard Pump Rooms.
COAST GUARD RESEARCH AND DEVELOPMENT CENTER GROTON CONN
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The results of the explosion suppression test series conducted in the forward pump room of the tanker RHODE ISLAND internal volume of 18,120 cu ft are reported. Propaneair and n-Hexaneair mixtures near stoichiometric were used in 10 percent of the pump room volume. The n-Hexane was explosively dispersed and ignited by a propane flame. The unsuppressed tests produced maximum pressures of 12 psig. The suppression attempt was unsuccessful because the pressure detectors, set to trigger the suppression system at 12 psig, were too slow. The propane was injected through two 12 inch pipes and a delay time was provided between injection and ignition to permit the fuel to become quiescent. Upon ignition, the pressure developed very similarly to the n-Hexane explosions and more rapidly than expected. This was finally attributed to obstructions creating turbulence which increased the flame speed and thus the rate of pressure rise. Ultraviolet detectors detected the incipient explosion from 110 to 400 milli-seconds before a pressure detector set for 12 psig. Two explosion suppression systems were tested. They each were based on the following principles 1 a UV detector sees the incipient explosion, 2 the control circuitry fires initiators, 3 the initiators rupture a diaphragm releasing a suppressing agent, 4 the agent is thrown at the flame front, and 5 the explosion is suppressed. In analyzing the tests, the size of the fireball at agent contact, agent breakdown, afterburning and the maximum pressure were considered.
- Organic Chemistry
- Marine Engineering
- Safety Engineering
- Ammunition and Explosives