FLOSS III is a third-generation version of a digital computer program which solves a one-dimensional difference representation of the momentum, energy, continuity, and state equations for turbulent, compressible gas flow in equivalent hydraulic channels. Extensive use of this program has been employed in the design and performance analyses of Pluto-type nuclear heat exchangers, and in the specific case of the Tory II-A test series, agreement was obtained to better than 5% for all experimentally measured parameters. The NOMAC and DASH-N programs combine the effects of up to thirty varieties of channels with the dependent boundary conditions imposed by a common inlet diffuser and exit nozzle. The resulting calculations yield performance information for blow-down facility and ramjet flight condition application of the heat exchanger.

Project Sherwood is a nation-wide attempt to produce a controlled thermo-nuclear fusion reaction. The Astron experiment, conceived by Nicholas Christofilos, will utilize the effects of a cylindrical layer of relativistic electrons to contain and heat the plasma. A high quality, 200-ampere, 5-Me V electron beam is required to form the electron layer. The electron beam is produced by a linear induction electron accelerator. Three hundred and thirty-three toroidal cores of magnetic material surround an evacuated ceramic accelerating column. The electrons are accelerated by the transverse electric field produced by the changing flux. The magnetic cores are tape-wound toroids of .001", 50% Ni - 50% Fe. Two hundred eighty-eight cores are 24" o.d. x 8-1/2" i. d. x 1/2" thick and the remaining forty-five are 33" o. d. x 18" i. d. x 1/2" thick. Each core is required to support 16 kG for 0.4 psec. The choice of magnetic material was made by testing all available material for the required parameters. Results of these tests are presented.

The theory of the hydrodynamic origin of cosmic rays proposed by Johnson and the author (Colgate) has developed to the point where the final evolution of a star to the supernova instability and subsequent explosion can be described with sufficient detail such that cosmic rays with appropriate intensity, composition, and spectrum to account for observations are a logical and necessary result. In the first publication it was pointed out that nuclei in the surface of the star may acquire many orders or magnitude more than the average energy per particle released in the explosion because of the large ratio of matter density between the core and the outer mantle. A shock from a sudden pressure increase in the core intensifies as it advances into lower-density material, thereby imparting extreme relativistic energies to the outermost layers. The shock wave was assumed on the basis that the observed explosion occurred in a time short compared to the traversal time of sound across the dimensions of the star. It was argued without proof that an adiabatic process would be inconsistent with the accepted gravitational instability as the trigger mechanism. In an attempt to confirm this supposition we extend the hydrodynamic calculations to describe …

A phase shift analysis is an attempt to translate experimental measurements (observables) into well-determined scattering amplitudes, since these are the quantities that can be readily compared with theoretical predictions, In this sense, the phase shift analysis should contain as little theory as possible. The scattering amplitudes (or phase shifts) constitute an experimental statement, and the phase shift analysis should logically be done by the experimental groups who measure the observables.

This scaler was designed to replace an obsolescent tube design that was in general use at Lawrence Radiation Laboratory in Livermore. The new design, using solid state devices and printed circuit modules, allows two complete scalers in one frame to occupy the same rack space as the tube design. Switches in the input circuits of the new scaler change input impedance and sensitivity for operation with either tube or transistor circuits. The use of transistors has greatly increased reliability, and has also reduced power by a factor of fifteen. Modular construction of all circuits, including the power supply, minimizes down time since all modules are replaceable without removing the scaler from its rack. Reliability, then cost, were the criteria dictating choice of components and circuits in the scaler design.

The transient aerothermodynamic processes in a gas-cooled reactor are described in a simplified manner to illustrate some of the fundamental physical phenomena involved, to provide some approximate but useful methods of analysis, and to aid in the understanding and use of more complex computer solutions. The transient heat balance equation for an element of a single reactor channel is derived in terms of aerothermodynamic time constants, and typical analytic solutions for transients are presented. This equation is used in generating the time-dependent equation for the channel exhaust gas temperature. The single-channel analysis is extended to multiple channels. A method for determining the approximate transient temperature envelopes for various reactor components is presented. The effects of aerodynamic and thermal coupling between different reactor channels are illustrated. Some of the simplifying assumptions are investigated with respect to the conditions under which they are valid.

It has been shown that the time of burst of exploding wires can be predicted from known thermodynamic and electrical properties of the wire materials under some conditions. The mathematical relationships are a set of integrals (transformation time integrals) similar in form to the empirical "action integrals" sometimes used in exploding wire work. This paper discusses the use of the transformation time integrals to calculate the resistance and temperature of a wire as a function of time up to the time of burst and to investigate the effects of environment of the wire on the temperature, resistance, and time of burst.

Nuclear excavation is the name given to the concept of using large scale nuclear explosion craters for useful projects, such as harbors, canals, and roadway cuts. It is one of the principal applications of the Plowshare Program for industrial, or peaceful, uses of nuclear explosives. Plowshare is sponsored by the U.S. Atomic Energy Commission and is under the technical direction of the Lawrence Radiation Laboratory at Livermore, California. The purpose of this paper is to describe cratering concepts and the present state of nuclear excavation technology. The general nature of the safety hazards associated with nuclear excavation are also discussed.

If a piston with constant velocity moves into a shock tube containing material at rest and at uniform density, the result is well known and trivial. The shock propagates with uniform speed, the state and speed of the material behind the shock is constant. One can ask if similar flows exist for cylindrical of spherical symmetry. Quickly one rules out the possibility of a solution which retains all the properties of this trivial solution. One asks if there are any solutions such that the material behind the shock is not accelerated. Indeed, there are. In the following, it is shown that for a y-law gas, there is a family of densities such that if a piston moves into the material with uniform velocity, the material behind the shock is not accelerated. Further, these are the only densities with this property. In the case of planar symmetry, the trivial case mentioned above is a member of the family, as is to be expected.

Recent underground nuclear tests conducted by the U.S. Atomic Energy Commission have yielded data on the effects of contained nuclear explosions in four rock mediums: tuff, alluvium, rock salt, and granite. This report presents and compares data obtained primarily through exploratory mining and drilling into the postshot environment of 35 such events.

The calibration of mercury vapor detectors has always posed a problem because of the difficulty of generating known concentrations of mercury vapor in air. The purpose of this study was to design an apparatus that would generate and chemically measure known concentrations of mercury vapor in air for calibration work.

Late in 1962, a group in the Computation Division at Lawrence Radiation Laboratory, Livermore, began a study of compiler languages and techniques, the culmination of which was a machine independent FORTRAN written in FORTRAN. The impetus behind this study was a local need to move rapidly and efficiently from one machine to another. A secondary incentive was the need to be able to implement language extensions without the customarily long gestation period. Because of a large inventory of FORTRAN codes at this installation, FORTRAN source language was chosen as standard. Some effort was also expended on a syntax directed compiler written in FORTRAN for FORTRAN. With the knowledge of FORTRAN techniques gained from writing the syntax compiler and translators for other machines, the writing of FORTRAN in FORTRAN was begun.

Calculations of the photonuclear giant resonance according to the Wilkinson model are presented in this report. In this model the giant resonance in the cross section for absorption of gamma rays by nuclei is ascribed to the excitation of large numbers of nucleons in closed shells. The model generally predicts correctly the integrated cross section for the giant resonance, bu the resonance energy is too low. Results are presented in a series of tables and formulas so that the integrated cross section may be calculated for any given nucleus.

In this study, a physical-numerical model is used to investigate processes important for cratering, or excavation, physics for high-explosive sources in desert alluvium. High explosives do not vaporize much of the geological environment surrounding the initial cavity containing the explosive. Thus, a relatively simple, and in some cases a well-known, equation of state exists for the high-explosive cavity gas for pressure greater than 1 atmosphere. However, nuclear explosives are known to vaporize a great deal of surrounding geological environment during the early part of cavity life history. This vaporized material is believed to condense late in the life history of the cavity, and prior to vent of the cavity gas to the atmosphere, such that the latent heat of condensation plays an important role in nuclear excavation. So far, no numerical-physical models of the response of a geologic environment to a nuclear explosive includes the effect of condensation on the hydrodynamics of late times. Thus, the calculation of the cavity pressure at late times including the effect of condensation is one of the current unsolved problems in the calculation of a crater formed by nuclear explosives. This study, then, develops a predictive, numerical-physical model for H.E. sources of the cavity …

The production of energy by nuclear reactions results in the production of radioactive nuclei. Therefore, in considering the possible utilization of nuclear explosives for peaceful purposes it is necessary to be able to predict the expected activities, their amounts, and dispositions. The amounts and kinds of radioactivities produced by detonation of a nuclear explosive are dependent upon the specific design of the explosive. The behavior and ultimate fate of the activities produced by the explosion depend on the composition of the medium in which the detonation occurs, the nature of the detonation, and the chemical species involved.

In any underground nuclear explosion, the shock front that propagates from the shot point carries with it energy from the explosion, and distributes this energy by doing work on the surrounding material. In the process, the material undergoes changes in both its physical and mechanical states. If enough energy is deposited in the material, it will vaporize or melt thus changing its physical state, or cause it to crush or crack. During the past few years, special computer codes have been developed for predicting the close-in phenomena of underground nuclear explosions using the laws of physics, and the knowledge of the properties of the materials in which the detonations occur. As a consequence, a better understanding of experimental observations and measurements has evolved.

The effects of explosion-induced ground motion must be evaluated in planning and executing any nuclear excavation project. For some projects ground use intensity may dictate the use of less-than-optimum yields to minimize damaging effects. In remote areas, weighing the alternatives of outright purchase of some property or use of smaller yields may be required. The cost of indemnifying owners against damage must be considered in any case. Discussions of the effects of ground motion on three broad types of facilities - engineered structures, residential buildings, and equipment required for the support of nuclear excavation operations - are presented. A method of predicting the response of single- and multi-storied buildings, the response spectrum technique, is discussed, with emphasis on the application of explosion-induced spectra.

In November 1952 an event took place which was to have a profound effect on political alignments of the world. This event was the detonation of "Mike", the first large thermonuclear device. The political implications of this experiment overshadowed what has come to be a major advance in the development of scientific tools; the experimentally verified, extremely high thermal neutron flux observed in Mike. Subsequent to this observation, the Atomic Energy Commission established a study program to investigate this particular characteristic of nuclear devices. Under the program, Los Alamos Scientific Laboratory and Lawrence Radiation Laboratory, Livermore, have studied the mechanisms of high fluxes, capture systematics, general stability characteristics, and more specifically, nuclear design to accomplish this massive neutron irradiation. Utilization of these greatly increased fluxes can be expected to significantly advance understanding in many fields.

Over the past 13 years a considerable body of data on explosive cratering has been developed for application to nuclear excavation projects. These data were obtained from some ten cratering programs using chemical explosives (TNT or nitromethane) and seven nuclear cratering detonations. The types of media studied have ranged from marine muck to hard, dry basalt, although most effort has been devoted to craters in NTS desert alluvium and basalt. Considerable effort has also been devoted to the study with chemical explosives of the use of linear explosives and rows of point charges. This paper is intended to be a summary of these data and a statement of the understanding which has been developed from them.

LRL has the responsibility of demonstrating the feasibility of a reactor for use as a power plant for a low-altitude, high-Mach-number missile. This reactor is literally a very high power air heater which must work at temperatures in excess of 2000' F. The reactor is exposed to high loads so one of the primary problems is providing high temperature structure. Considerable effort has been devoted to developing ceramic structural elements. One of the materials considered for this purpose is silicon nitride. In ceramic structural elements operating over large temperature ranges, a major problem is coping with thermal stress. In this respect there is a similarity with the radome problem. The work on silicon nitride at LRL consisted of limited fabrication studies (principally for familiarization), measurement of properties of interest to the application, and funding of fabrication scale-up efforts.

A fraction of the energy released by the underground detonation of nuclear explosives is locally deposited as residual thermal energy. An accurate prediction of this usable fraction of the energy released is necessary to evaluate the feasibility of several of the proposed projects in the Plowshare Program. This paper will present a summary of the available data on residual thermal energy from nuclear detonations in three different geological media: tuff, halite, and granodiorite.

The Chapman-Jouguet pressure and equation of state of the high explosives PBX 9404 and LX04-01 have been experimentally derived. To assure a strictly one-dimensional geometry, spheres of high explosives were used. Experimental measurements of the radius-time history of material accelerated by the explosive gases were used in conjunction with finite difference calculations of the hydrodynamic equations to obtain some previous inaccessible data on high explosives.

In the course of modern physics research, the need frequently arises for storage of large quantities of electrical energy which can be periodically discharged at high peak power into a load. Until recently, the homopolar machine has been an intriguing device having considerable academic interest but little practical value. In recent years, successful machines have been developed to utilize liquid-metal brush systems. The liquid-metal brush overcomes all the problems associated with current collection power loss, frictional loss, and limiting peripheral velocity. Consequently, these machines are now worth serious consideration where high-current dc generation is required. The main purpose in setting up a homopolar generator test program was to establish the limits to which an essentially standard commercially available generator of this type could be pushed.

The angle errors of a rotary table can be accurately measured by stepping off the angles with an optical caliper and computing table error from (1) the error readings at each angle measured and (2) the cumulative caliper error that will be evident when the circle is closed at 360', eliminating the necessity of adjusting the caliper to the exact setting.