eddies is accomplished by a signal correlator and their transit time is determined by an on-line computer. Tests in water at velocities from 1 to 16 feet per second have shown the technique to be capable of an accuracy of 2 percent. Work is being planned to investigate and test a similar system in sodium to temperatures of 1200°F.

p

In a number of applications pulsed-electromagnetic fields offer some important advantages over the sinusoidal fields used in conventional eddy-current testing. Inspection equipment for fuel-element cladding has been developed that can detect defects in tube walls equal to or greater than 5 percent of the wall thickness at an inspection rate of 10 meters per minute. Equipment has also been constructed that can locate voids and measure their depth in the sodium bonds of fuel elements and capsules to 2 millimeters below the surface. Pulsedelectromagnetic methods were recently used for the first time to measure the motion of fuel inside a fuel element undergoing a transient irradiation in TREAT.

Holography

Equipment to make and display three-dimensional, wave-front-reconstructed images (optical holograms) has been installed at ANL, and several optical holograms have been made. This technique shows great promise for nondestructive testing applications since highly magnified, three-dimensional images of the interior of opaque objects are possible. The various experimental techniques and difficulties associated with this method are being studied. An experiment at the CP-5 reactor to determine the feasibility of making holograms with a monochromatic neutron beam was not successful.

REACTOR PHYSICS COMPUTER CODE DEVELOPMENT

A digital computer code system called the ARC (Argonne reactor computation) system has been placed into operation at ANL to facilitate the solution of complex reactor theory and design problems.

30-622 0-69-pt. 4- -24

You will note the foreign LMFBR's that are scheduled to come on line in the next 5 to 10 years-the Phenix, a 250-megawatt reactor, in France; the PFR, a 250-megawatt plant being built now in Great Britain; and in Russia they are going with three plants at one timethe BR-60, a 60-megawatt-electric LMFBR reactor, the BN-350, which is a 150-megawatt-electric LMFBR demonstration reactor, as well as their BN-600, a 600-megawatt-electric LMFBR demonstration

reactor.

and Reso

Tommendati

lading nuc

Supported by ceanogr

Mr. RAMEY. The Soviets are connecting a desalting plant to their BN-350 plant. It is being built in the Caspian area. It is supposed to be completed this year or next year. We figure they may have a few start-up problems to iron out.

(Off the record.)

TERRESTRIAL ELECTRIC POWER DEVELOPMENT

pro

Marine St

Mr. BOLAND. On page RD 62, $4,400,000 is budgeted to continue the terrestrial electric power development program. What is the urgency of maintaining this program at this level in fundi fiscal year 1970?

r

Mr. SHAW. The fiscal year 1970 budget request represents a signified t cant reduction from prior fiscal year 1968 funding level of $6 million. As a result of this reduction, which was ordered as a result of overall

WAP-2

budget economy, the terrestrial electric power program has deferred re and canceled a number of important programs and presently is concentrating only on those programs that have the highest priority need.es These include the development of (1) miniaturized Pu238 power sources ti for use in biomedical engineering applications including the cardiac pacemaker and intelligence-gathering communications applications com and (2) low power (<100 watts) Sr sources for oceanographic and marine activities. Although the AEC is restricting its efforts to these T critical programs, it should be noted that each of these programs has, as b a result of budget stringency, been extended by at least 1 to 2 years. Furthermore, the current budget level does not permit AEC to start necessary development of large isotope-powered (1 to 10 kilowatt) power sources projected for use with active ASW sonar arrays. This latter program has been designated by the Department of the Navy as a top priority program and AEC support of this activity is being requested. Necessary development must, however, be deferred until fiscal year 1971 at the earliest.

In regard to the current efforts involving Sro power sources (SNAP-21/23) it must be emphasized that the need for these isotope power sources is closely coupled with the national program of ocean engineering and exploitation which represents an increasingly significant national priority program. The National Council on Marine Resources and Engineering Development, established by the Congress in 1966 for the specific purpose of establishing a national marine sciences program, has clearly recognized the need for reliable and long endurance power sources. The Second Report of the President to the Congress on Marine Resources and Engineering Development (1968) identifies the absence of long endurance power sources as haps the most critical, unmet need of underwater technology." Furthermore, the report of the Commission on Marine Science Engineer

66* * *

per

ing and Resources issued in January 1969 has, as one of its major recommendations, the continuing technological development of power systems necessary for underseas operations and resources development, including nuclear systems. These recommendations have been strongly supported by the Department of Defense, Government agencies, and the oceanographic community in numerous studies and reports. The capability of nuclear power devices to provide long endurance in the sea-water environment over a wide range of power represents the single most important characteristic associated with these devices particularly in comparison with existing energy sources. As a result, the AEC has been under significant pressure to accelerate and expand its current terrestrial and marine power sources development program. Due to budget considerations, no acceleration is permissible in fiscal year 1970. The requested fiscal year 1970 funding represents the very minimum necessary to carry out an orderly and meaningful technology development program.

As an illustration of the effect of the stretchout resulting from current funding levels, it should be noted that both the Commission on Marine Science Engineering and the National Council have recommended the development by this Government of a worldwide weather buoy network as a priority undertaking. The capability of this buoy network may be significantly enhanced from a reliability and endurance viewpoint by the use of compact radioisotope power sources of the SNAP-23 design. The present rate of development on the SNAP-23 power source will, however, delay the availability of these devices to the 1974 time period which is presently incompatible with the Coast Guard's plans for development, testing and evaluation of buoy systems and components. As a result of this incompatibility, the SNAP-23 device may not be available for consideration in this critical application. Therefore, the effects of current program stretchout resulting from budget stringencies is already having significant impact. Furthermore, other important applications including nuclear detection seismological stations have similarly been compromised by current program delays. Any further reduction in funding levels will have even more significant impact from a utility and timeliness standpoint.

GENERAL REACTOR TECHNOLOGY

Mr. BOLAND. Beginning on page RD-66, $47 million is requested to continue the general reactor technology program.

Please highlight some of the results under this work during the past

year.

Mr. SHAW. Continuing direction and focusing of the general reactor technology (GRT) programs toward the near term as well as advanced technology requirements of the priority reactor development programs was emphasized throughout the year. The results of these endeavors can best be measured in terms of improved technical problem definition, unique experimental methods developments, a continuing expansion of the depth and breadth of knowledge in reactor technology and new technical hypotheses supported by experimental results.

The GRT program activities provide the base technology on reactor fuels and materials, basic engineering developments for reactors and their fuel cycles, reactor physics and chemistry. Pertinent examples

and highlights from the past year's GRT program activities are reported herewith.

SWELLING OF NUCLEAR FUELS

infor

arle, the at are hig

Some insight into the basic mechanisms and factors which controltage 4. the swelling of nuclear fuels under irradiation has been obtained at the Columbus Laboratories of Battelle Memorial Institute. These studies suggest that the swelling of nuclear fuels can be described in terms of four stages which may occur in sequence or with overlaps depending upon the temperature and other conditions. The four stages are illustrated in the chart (below) which shows the swelling behavior str of UO2.

Stage 1 involves a period of time in which the insoluble fission-gas atoms diffuse through the fuel and precipitate as diatomic or larger gas bubbles. The pressure of gas in these nearly stationary and spheri cal bubbles causes the fuel to swell, and this swelling is opposed primarily by the creep strength of the fuel and its cladding.

Stage 2 involves a period of time in which these bubbles begin to move through the fuel under the influence of stress or temperature gradients. Such moving bubbles are not spherical and will encounter other gas atoms and bubbles and swell the fuel as they grow larger.

Stage 3 is characterized by the formation of channels which inter connect the bubbles containing the fission gas with external void