The ETC activities at FOI - Weapons and protection during 2004
Publish date: 2004-01-01
Report number: FOI-R--1397--SE
Pages: 57
Written in: Swedish
Abstract
The report accounts for the work performed at FOI - Weapons and Protection during 2004 within the electrothermal-chemical (ETC) launching technique area. Modelling of a plasma generator for plasma initiation has been studied and a theoretical derivation for an axial plasma generator is presented. Translucent gun propellants have shown to be more suitable for ETC-applications than for related graphited propellants. Absorption measurements have been performed on some received translucent propellants and show that inhomogeneous parts of the propellant has a greater effect on the transparency of the propellant than the thickness of the propellant. Conductive flame experiments performed in closed vessel on translucent gun propellant tend to show that the effect on gun propellant burning rate by addition of electrical energy is significantly higher than for other, earlier examined propellants. This is to be confirmed by further experiments, though, to be able to determine the importance of the transparency of a gun propellant. An evaluation of high-pressure (100 MPa) discharge phenomena on ETCexperiments performed so far, shows that an arc discharge takes place after dissipation of 0.2-0.4 kJ and at a power of 0.1-0.5 MW during the discharge process. A concept were different types of conducting foils can be used for propellant ignition, is also described. Continued work on plasma ignition and translucent gun propellants, both in CF experiments and in plasma ignition experiments, is planned. The modelling of a plasma generator is continued in further work, together with interior ballistics modelling. A continued collaboration with foreign research groups within the ETC area is also planned.