Tests were run at the General Electric Company, Atomic Power Equipment Department, to determine the burnout conditions for a non-uniformly heated rod in an annular geometry.

The nuclide Cs-137 is a fission product commonly used for measurement of uranium burnup in irradiated uranium fuel by the fission product to uranium ratio method. In the application of this method, the largest single error introduced in the measurement of burnup is the uncertainty in the half-life of Cs-137. Because of the uncertainty in this value and its importance in nuclear fuel burnup analysis, a reinvestigation was undertaken to obtain a more accurate value using the mass spectrometric method.

Work performed during the quarter is summarized by direct measurement of fission gas pressure, loop modifications, UO2 fuel performance

The General Electric Company is designing and building a 180,000 kilowatt nuclear power plant for the Commonwealth Edison Company at a site 47 miles southwest of Chicago. The construction permit was issued on May 4, 1956 but is subject to submittal to the Commission of a final hazards summary report and a finding by the Commission that the final design provides reasonable assurances that the health and safety of the public will not be endangered by operation of the reactor in accordance with the specified procedures.

This report describes progress made in the study of the feasibility of the concept, plant arrangement studies, and considerations pertaining to partial plant attendance. It is concluded that both the indirect and direct boiling cycles are feasible. The recommended reference design is the direct cycle, in a single capsule, with the turbine, generator and pumps on a single shaft.

The pressure drop of a new fuel element design concept of spacing rods by means of helical wire springs was investigated experimentally and analytically.

A code (RAPTURE) was programmed for the Philco TRANSAC 2000 computer to perform calculations needed for the evaluation of Doppler Coefficients in fast reactors with degraded neuron spectra. This code computes resonance integrals, averages them over resonance parameter distributions, and computes fission and capture cross sections as a function of fuel temperature and of potential scattering cross section per absorber isotope.

In concurrent flow of two phase mixtures there exists a velocity difference between the vapor and liquid phases. This difference in velocity is known as the slip velocity. The prediction of slip is the subject of Part I. In boiling systems there is some heat transfer rate at which nucleste boiling becomes unstable. At this point the separate bubbles coalesce forming an insulating vapor film on the heat transfer surface resulting in the destruction, or burnout, of the heater. The prediction of the conditions causing burnout is the subject of Part II.

The fabricability, elevated temperature strength, steam corrosion resistance, and hydrogen pickup of various binary, ternary, and quaternary alloys were studied experimentally.