Generation of hydrogen isotopes with an electricpulse hydride injector
Introduction
The idea of developing an electrical pulse hydride injector occurred in connection with theneed for a controlled supply of gaseous hydrogen isotopes, i.e., tritium, into large experimental fusioninstallations of the TOKAMAK type. The presently employed gas supply systems for this type ofreactor were originally developed for use with hydrogen and deuterium and use piezo valves asdosage elements. The piezo valve is installed in the gas pipeline and separates a gas at high pressurefrom the fusion chamber at vacuum. To achieve the required gas flow rate into the chamber, gasunder a pressure of a few bar and in an amount, which allows to maintain this pressure over the entiresupply time, is used. Thus, during operation with a deuterium/tritium mixture a substantial inventoryof gaseous tritium needs to be dealt with.
The EPHI is based on different principles. It keeps the hydrogen isotopes in a chemicallybound state on special absorbers. The dosed generation of gas occurs by heating selected absorberswith short, high current pulses. Detailed information on the EPHI is given in [1]. In this work,new data obtained with a new generation EPHI are reported.
Section snippets
Brief description of the EPHI-1C and the experimentalinstallation
EPHI-1C is a new-generation injector of hydrogen isotopes that can generate gas pulses inup to hundreds of s yielding more than 5.1021 molecules per shot. For the operation ofthe injector, the absorbers must first be saturated with hydrogen isotopes. The injector vessel is madeof stainless steel, at the ends of which flanges are welded (Fig. 1) . At equal distances from the flanges, a nozzle is installed on the cylindrical surface of the tube,through which evacuation of the injector, the gas
The main objectives of the experiment and experimentalresults
The main objectives of the present experiments are:
•definition of the conditions under which the titanium coated foils mounted in the injector aresaturated up to a condition, which is defined by the chemical formula TiD;
•investigation of deuterium liberation from the foils;
•quantification of the deuterium absorbed by the foils;
•definition of quasi-equilibrium pressures of deuterium as a function of the current passingthrough the foil and of the titanium saturation with deuterium.In preliminary
Discussion
As apparent from Fig. 4, the principle course of the pressure curves as a functionof time does not vary when the deuterium generation conditions are changed. The rise of pressureis decelerated with time (or number of current pulses) . By increasing the current, the requiredamount of deuterium can be released from the foil within a shorter period of time. For example,whereas at a current of 12 A the first 1 mbar is obtained in about 2200 s and the second 1 mbar inabout 3500 s, at 17 A the time
Conclusion
It is shown that the EPHI concept is suitable for the repeated dosage of hydrogen isotopeswithin a broad range of gas inventories. Prior to technological implementation further work on thelaws of gas saturation and generation is still needed. In addition, the techniques for manufacturingthe foils should be further improved.
References (3)
- Azizov EA, Kareev YuA, Savotkin AN, Frunze VV, Penzhorn RD, Glugla M. An Electrical PulseHydride Injector (EPHI) for...
Cited by (2)
On an Electric Pulsed Hydride Injector for gas puffing into tokamaks
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2006, Instruments and Experimental Techniques