The investigation of processes in the discharge chamber of ETH-launchers which influence their operation efficiency

Summary form only given. The basis of the electric discharge launcher is the discharge chamber in which the arc´s electric energy conversion into the internal energy of the working gas takes place. The main possible mechanisms of the heat transfer from the arc´s column at the current of about 1 MA to the surrounding gas (hydrogen) at the initial concentration of 3/spl middot/10/sup 22/ cm/sup 3/ are analyzed. The peculiarity of the heat transfer process is the existence of the initiating wire and of the electrodes´ material atoms, the concentration of which is equal to 10/sup 19/-10/sup 20/ cm/sup 3/. The arc´s temperature is determined on the basis of conductance, obtained in the experiments. The shock waves, converted into acoustic ones are found. Average mass gas temperature is estimated due to the velocity spreading. The increase of gas heat efficiency with the growth of its initial pressure has been registered. It proves the fact of gas heat owing to shock wave energy and owing to the energy absorption, radiated by the arc. Significant experimental material has been accumulated in the spheres of development, investigation and exploitation of the present type of launchers. Basing on its qualitative analysis the conclusions are made relative to the possible ways of operation efficiency increase for the facilities of this type. A set of dependencies such as: conversion coefficient of the input electric discharge energy, converted into the hydrogen internal energy, depending on the initial gas pressure; the velocity of the mass bodies versus the input electric discharge energy and versus the accelerated body mass at the fixed energy values (in the masses range of 3-250 g, energy up to 2/spl middot/10/sup 6/ J and velocity-up to 6 km/sec) is presented. The energy balance chart of a launcher of 31 mm caliber is given.