Spectral Pyrometry of Dusty Plasma During an Electric Explosion of a Tungsten Wire

It is well known that the optical spectrum of the radiation produced during the electric explosion of tungsten wires (EEW) in vacuum is composed of both line and continuous components. A detailed description of a spectral pyrometry method is presented, which allows one to use the shape of the Planck component of the continuous spectrum to determine the effective temperature of the explosion products. The effect of temperature growth during the EEW on the measurements of effective and maximum temperatures is discussed. Results are presented from numerical simulations of temperature for different time dependences of its dynamics. It is shown that, under the linear approximation of temperature growth, the calculated results agree satisfactorily with experimental data. It is shown that, when the wire reaches the tungsten boiling point, no Planck continuous spectrum is observed. The developed method allows one to estimate the absolute luminous flux during EEW. It is shown that the light radiation from EEW products is volumetric. Additionally, during the electric explosion, an extra continuous spectrum—relative to the Planck spectrum—is observed in the 360–500 nm wavelength range, which is produced by nonequilibrium radiation. The characteristics of this nonequilibrium radiation and its dependence on the diameter of the exploding wire were obtained and possible mechanisms of its production are also discussed.