The first screw extruder capable of continuously forming macroscopic solid
hydrogen particles to be injected into the plasma of thermonuclear devices
was created and successfully tested. A model of nonisothermal hydrogen flow
in the screw channel was developed and used to calculate the extruder effi
ciency as a function of the system parameters. The results of calculations
and experimental data are presented for the extrusion of 500 cm(3) of solid
hydrogen using an extruder with a working volume of 8 cm(3) operating at a
rate of 63 mm(3)/s. Temperature dependences of the viscosity and shear str
ength of solid hydrogen were studied in the temperature interval from 10 to
13 K, where solid hydrogen behaves like a Bingham fluid. (C) 2000 MAIK "Na
uka/Interperiodica".