A summary of the Brayton Isotope Power Systems (BIPS) design layout drawings is presented. These drawings were generated in compliance with Task 3 (Preliminary Design of the BIPS Ground Demonstration System) of Phase I of the ERDA sponsored BIPS contract E(04-3)-1123.

The performance of an idealized geothermal binary-fluid-cycle energy conversion system is shown to be a function of the temperatures of brine and working fluid leaving the heat exchanger. System power output, heat exchanger area required and initial well and heat exchanger costs are determined for counterflow, single and multi-pass parallel-counterflow exchangers. Results are presented graphically as functions of the brine and working fluid exit temperatures from the exchanger. Use of the system analysis developed is illustrated by showing quantitatively the advantage of the counterflow over the other flow arrangements considered.

A compendium of miscellaneous documents, memos, and progress report extracts for the Brayton Isotope Power System Ground Demonstration System Preliminary Design Review is presented. The document does not represent a formal interim or final report, but is furnished to aid the customer in evaluating the progress of the ERDA BIPS GDS design.

These materials were stacked together for irradiation by the LLL rotating target neutron source. A description of the samples is included along with data on dosimetry. (JRD)

The ''wide'' ribbon machine, JPL No. 1, is satisfactorily nearing completion. Heat sinks to accelerate growth rates were tested. Although horizontal gradients can be tailored with the heat sinks, no growth rate improvement was realized. The electrical effects of linear boundaries have been studied. Thin ribbon growth as an immediate task is reconsidered.

A summary is presented of studies of the heat transfer and pressure drop characteristics of extended surfaces. The summary is based on data that were compiled and analyzed with the objectives of determining the effects of geometrical configurations of an extended surface tube bank on its heat transfer and pressure drop characteristics. A generalized correlation of heat transfer and friction losses was developed on the basis of this analysis. These correlations can be used to predict the performance of an extended surface tube bank of specified geometry and flow conditions.

The crystal-growth method under investigation is a capillary action shaping technique. Meniscus shaping for the desired ribbon geometry occurs at the vertex of a wettable die. As ribbon growth depletes the melt meniscus, capillary .action. supplies replacement material. In this report, a new capillary die design is described. It represents a departure from the die types used for edge-defined, film-fed growth, in that the bounding edges of the die top are not parallel or concentric with the growing ribbon. The new dies allow a higher melt meniscus with concomitant improvements in surface smoothness and freedom from SiC surface particles, which can degrade perfection. Also in this reporting period, ribbons were grown for delivery to JPL. Twenty ribbons and 30 ribbon samples were shipped. Detailed dimensional characteristics of most ribbons grown during the past year are presented. Finally, our initial progress in the growth of 38-mm (1-1/2-inch)-wide ribbons, up to 46 cm in length, is reported.

A compendium of flight system preliminary design internal memos and progress report extracts for the Brayton Isotope Power System Preliminary Design Review to be held July 20, 21, and 22, 1975 is presented. The purpose is to bring together those published items which relate only to the preliminary design of the Flight System, Task 2 of Phase I. This preliminary design effort was required to ensure that the Ground Demonstration System will represent the Flight System as closely as possible.

A test program was conducted to determine the fatigue behavior of LHTGR fuel element dowel/socket systems. Two dowel/socket systems, namely, a four-dowel system and a five-dowel system, were tested to failure under shear loads applied through a fatigue test apparatus to simulate repetitive loading during a seismic event.

There is an abundance of salt domes in the Gulf Coastal region. Advances in leaching technology and cavern shape control make it possible to build large caverns with configurations approaching teardrops, cylinders, and spheres. Fenix and Scisson has designed and constructed several dozen caverns in sizes up to three million barrels (16.8 million cubic feet). It is now within current technological bounds to evacuate the brine left in the cavern following construction, dehumidify the cavern atmosphere and supply conditioned cavern ventilation. The state-of-the-art in drilling large diameter holes has advanced to the point that it is now possible to drill 120-in. holes as deep as 6,000 ft and 144-in. holes to lesser depths. Additional research is needed in the area of cavern stability. Cavern shrinkage rates are known to increase with depth because of lower salt strengths at higher pressures and temperatures.