| 摘要 |
<p>The invention is for discriminating between the explosion of an ammunition round itself and the fire or explosion which may then take place in the object struck by the round and for initiating suppression of the latter fire or explosion only. The object may, for example, be an armoured vehicle in which it is desired to initiate fire or explosion protection action when the exploding ammunition round causes or is about to cause fire or explosion of the hyrocarbon fuel but not to cause suppression action when the only fire or explosion is that of the round itself. The vehicle 5 carries a radiation detector 10 which measures the ratio of the intensity of the radiation at 3.4 and 4.4. microns. When (Figure 1B) an exploding ammunition round passes through the fuel tank 8 entraining initially unburning hydrocarbon fuel D with it, the detector 10 measures a relatively low ratio because the unburning hydrocarbon fuel vapour between the burning round and the detector 10 has a very intense absorption band at 3.4 microns. Fire suppression is thus initiated, so as to suppress the hydrocarbon fire which would very shortly follow. If the round (Figure 1A) does not strike the fuel tank 8, hydrocarbon fuel vapour is not present in the vicinity of the exploding ammunition round and the ratio measured by the detector 10 is higher and explosion suppression is not initiated.</p> |
