COMPARATIVE STUDY OF THE MORE PROMISING COMBINATIONS OF BLANKET MATERIALS, POWER CONVERSION SYSTEMS, AND TRITIUM RECOVERY AND CONTAINMENT SYSTEMS FOR FUSION REACTORS

摘要

The many possible combinations of blanket materials, trit¬ium generation and recovery systems, and power conversion sys¬tems were surveyed first by reviewing the principal design studies that have been prepared and then by examining a compre¬hensive set of designs generated by using a common set of ground rules that included all of the boundary conditions that could be envisioned. The results indicate that, of the wide variety of systems that have been considered, by far the most promising employs lithium recirculated in a closed loop within a niobium blanket structure and cooled with boiling potassium or cesium. This approach gives the simplest and lowest cost tritium re¬covery system, the lowest pressure and thermal stresses, the simplest structure with the lowest probability of a leak, the greatest resistance to damage from a plasma energy dump, and the lowest rate of plasma contamination by either outgassing or sputtering. The only other blanket materials combination that appears fairly likely to give a satisfactory tritium generation and recovery system is an Li2BeF4-Incoloy blanket, and even this system involves major uncertainties in the effectiveness, size, and cost of the tritium recovery system. Further, the Li2BeF4 blanket system has the disadvantage that the world reserves of beryllium are too limited to support a full-blown fusion reactor economy, its poor thermal conduc-tivity leads to cooling difficulties and a requirement for a complex structure with intricate cooling passages, and this inherently leads to an expensive blanket with a relatively high probability of leaks. The other blanket materials com¬binations yield even less attractive systems.