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Some preliminary design considerations for the ANS (Advanced Neutron Source) reactor cold source

Description: Two areas concerned with the design of the Advanced Neutron Source (ANS) cold source have been investigated by simple one-dimensional calculations. The gain factors computed for a possible liquid nitrogen-15 cold source moderator are considerably below those computed for the much colder liquid deuterium moderator, as is reasonable considering the difference in moderator temperature. Nevertheless, nitrogen-15 does represent a viable option should safety related issues prohibit the use of deuterium as a moderating material. The slab geometry calculations have indicated that reflection of neutrons may be the dominant moderating mechanism and should be a consideration in the design of the cold source. 9 refs., 2 figs.
Date: January 1, 1988
Creator: Henderson, D.L.
Partner: UNT Libraries Government Documents Department

Symmetry of laser driven implosions

Description: The achievement of significant nuclear energy yields from laserheated pellets of thermonuclear fuel requires that the fuel be compressed to at least several orders of magnitude above initial density. Such compressions can be attained by spherical implosions, but because of the large compression ratios required, these implosions must be highly symmetrical. Calculations of the behavior of imploding spheres and shells by a spherical harmonic perturbation method, and by two-dimensional hydrodynamic codes within their limitations, have shown the importance of electron thermal conduction in the low-density ablation cloud of a pellet in bringing about the required symmetry. These calculations show that, at early time in the heating of a pellet when the ablation cloud is relatively small and cold, the symmetry requirements are most severe and call for as many as four laser beams. However, symmetry requirements at later times, when most of the laser energy must be deposited, may be met by as few as one beam. (auth)
Date: October 1, 1973
Creator: Henderson, D.B. & Morse, R.L.
Partner: UNT Libraries Government Documents Department

Fuel temperature determination for ICF microspheres

Description: The common heuristic expression for estimating thermonuclear burn in ICF microspheres far from bootstrap heating is often used for inversion to obtain peak temperatures from experimental data. It contains an ad hoc or fitted parameter and lacks some parameters of obvious influence in actual systems. We present an alternative expression, which may be usefully inverted and does not suffer these defects.
Date: August 1, 1980
Creator: Henderson, D.B. & Giovanielli, D.V.
Partner: UNT Libraries Government Documents Department

Effect of deviations from the Maxwell distribution on neutron production in laser targets

Description: Because of the brief duration of laser implosions and the small size of the pellets, one may be concerned that the ions never reach a Maxwell distribution or that the tail is lost by diffusion. This might have a large effect on <sigma v>, which depends heavily on the tail. We have calculated the ion distribution and the DT <sigma v>. Results are presented for the ratio of <sigma v> for a monoenergetic isotropic distribution to that for a Maxwell distribution, for the rate of approach of <sigma v> to the equilibrium value, and for the decay of <sigma v> due to fast ion losses. The main effect in the last case is due to energy losses, not to non-Maxwellian distribution. The effect is substantially different than previously reported.
Date: November 1, 1978
Creator: Henderson, D.B. & Petschek, A.G.
Partner: UNT Libraries Government Documents Department

Solubility, viscosity and density of refrigerant/lubricant mixtures

Description: This report presents results for low refrigerant concentration (70, 80, 90 and 100 weight percent lubricant) mixtures of the following fluids: CFC-12/ISO 32 naphthenic mineral oil, HCFC-22/ISO 32 naphthenic mineral oil, CFC-12/ISO 100 naphthenic mineral oil, HFC-134a/ISO 22 pentaerythritol ester mixed acid, HFC-134a/ISO 32 pentaerythritol ester mixed acid [number sign]1, HFC-134a/ISO 68 pentaerythritol ester mixed acid, HFC-134a/ISO 100 pentaerythritol ester mixed acid, HFC-134a/ISO 32 pentaerythritol ester mixed acid [number sign]2, HCFC-123/ISO 32 naphthenic mineral oil, HCFC-123/ISO 100 naphthenic mineral oil, HCFC-123/150 SUS alkylbenzene, HCFC-123/300 SUS alkylbenzene. These data have been reduced to engineering form and are presented in the form of a Daniel Chart. Equations are given along with statistical measures of goodness of fit.
Date: April 1, 1993
Creator: Henderson, D.R.
Partner: UNT Libraries Government Documents Department

Solubility, viscosity and density of refrigerant/lubricant mixtures

Description: This report presents results on low refrigerant concentration (70, 80, 90, and 100 weight percent lubricant) mixtures of the following fluids: CFC-12/ISO 32 naphthenic mineral oil; HCFC-22/ISO 32 naphthenic mineral oil; and HFC-134a/ISO 32 pentaerythritol ester mixed acid. These data have been reduced to engineering form and are presented in the form of a Daniel Chart. Scatter diagrams are given for the first fluid listed above, with the intent of illustrating the quality of data as well as providing the rationale for selecting the particular functional forms chosen to represent the experimental data. Equations are given along with statistical measures of goodness of fit.
Date: January 1, 1993
Creator: Henderson, D.R.
Partner: UNT Libraries Government Documents Department

Investigations into the Optimization of Multi-Source Strength Brachytherapy Treatment Procedures

Description: The goal of this project is to investigate the use of multi-strength and multi-specie radioactive sources in permanent prostate implant brachytherapy. In order to fulfill the requirement for an optimal dose distribution, the prescribed dose should be delivered to the target in a nearly uniform dose distribution while simultaneously sparing sensitive structures. The treatment plan should use a small number of needles and sources while satisfying the treatment requirements. The hypothesis for the use of multi-strength and/or multi-specie sources is that a better treatment plan using fewer sources and needles could be obtained than by treatment plans using single-strength sources could reduce the overall number of sources used for treatment. We employ a recently developed greedy algorithm based on the adjoint concept as the optimization search engine. The algorithm utilizes and ''adjoint ratio'', which provides a means of ranking source positions, as the pseudo-objective function. It ha s been shown that the greedy algorithm can solve the optimization problem efficiently and arrives at a clinically acceptable solution in less than 10 seconds. Our study was inclusive, that is there was no combination of sources that clearly stood out from the others and could therefore be considered the preferred set of sources for treatment planning. Source strengths of 0.2 mCi (low), 0.4 mCi (medium), and 0.6 mCi (high) of {sup 125}I in four different combinations were used for the multi-strength source study. The combination of high- and medium-strength sources achieved a more uniform target dose distribution due to few source implants whereas the combination of low-and medium-strength sources achieved better sparing of sensitive tissues including that of the single-strength 0.4 mCi base case. {sup 125}I at 0.4 mCi and {sup 192}Ir at 0.12 mCi and 0.25 mCi source strengths were used for the multi-specie source study. This study also proved inconclusive ...
Date: September 30, 2002
Creator: Henderson, D. L.; Yoo, S. & Thomadsen, B.R.
Partner: UNT Libraries Government Documents Department

Energy Efficiency and Renewable Energy Network (EREN): Customer satisfaction survey

Description: The Energy Efficiency and Renewable Energy Network (EREN) Customer Satisfaction Survey was developed and executed in support of EREN`s continuous quality improvement (CQI) plan. The study was designed to provide information about the demographic make up of EREN users, the value or benefits they derive from EREN, the kinds and quality of services they want, their levels of satisfaction with existing services, their preferences in both the sources of service and the means of delivery, and to provide benchmark data for the establishment of continuous quality improvement measures. The survey was performed by soliciting voluntary participation from members of the EREN Users Group. It was executed in two phases; the first being conducted by phone using a randomly selected group; and the second being conducted electronically and which was open to all of the remaining members of the Users Group. The survey results are described.
Date: April 22, 1996
Creator: Anderson, A. V. & Henderson, D. P.
Partner: UNT Libraries Government Documents Department

Disposal Critcality Analysis Methodology: BWR Benchmarks

Description: Computer code benchmarks using commercial reactor critical (CRC) data for boiling water reactor (BWR) fuel assemblies using the SCALE and MCNP code packages have been conducted. Depleted fuel inventories which take into account actinide and fission product concentrations are used to develop reactor critical models and the associated neutron multiplication factors. Bias calculated from this integral benchmark method will be applied to the disposal criticality analysis methodology to ensure the sub-criticality of spent commercial nuclear fuel forecast for emplacement into the proposed geologic repository at Yucca Mountain. Previous CRC benchmark calculations have been performed for startup tests for Cycles 13 and 14 of the Quad Cities Unit 2 BWR. Additional benchmarking activities have been performed and applied to evaluations of beginning-of-cycle (BOC) reactor critical models for Cycles 7 and 8 of the LaSalle Unit 1 BWR. Similar to the methodology used for ensuring sub-critical margin for spent nuclear fuel shipping casks, the proposed criticality analysis approach computes the neutron multiplication factor of arbitrary fuel assemblies placed in spent fuel waste packages that represents a bounding criticality model. This is accomplished by calculating spent fuel inventories with the SAS2H sequence of the SCALE code package and computing the neutron multiplication of the spent fuel assemblies in the waste package with MCNP.
Date: August 1, 1999
Creator: Henderson, D.P. & Salmon, D.A.
Partner: UNT Libraries Government Documents Department

Solubility, viscosity and density of refrigerant/lubricant mixtures. Quarterly technical progress report, 1 October--31 December 1992

Description: This report presents results on low refrigerant concentration (70, 80, 90, and 100 weight percent lubricant) mixtures of the following fluids: CFC-12/ISO 32 naphthenic mineral oil; HCFC-22/ISO 32 naphthenic mineral oil; and HFC-134a/ISO 32 pentaerythritol ester mixed acid. These data have been reduced to engineering form and are presented in the form of a Daniel Chart. Scatter diagrams are given for the first fluid listed above, with the intent of illustrating the quality of data as well as providing the rationale for selecting the particular functional forms chosen to represent the experimental data. Equations are given along with statistical measures of goodness of fit.
Date: January 1, 1993
Creator: Henderson, D. R.
Partner: UNT Libraries Government Documents Department

Solubility, viscosity and density of refrigerant/lubricant mixtures. Quarterly technical progress report, 1 April 1993--30 June 1993

Description: This report presents the results of experimental measurements on low refrigerant concentration mixtures (0, 10, 20,30 wt %) of twelve working fluids. These data have been reduced to engineering form and are presented in the form of a Daniel Chart and a plot of density versus temperature and composition. Extensive numerical analysis has been performed in order to derive equations which allow two independent variables (temperature and composition) and to provide for corrections in composition due to vapor space volume in the test apparatus; details of these calculations are provided in Appendix A. This report supersedes all previous reports.
Date: October 1, 1993
Creator: Henderson, D. R.
Partner: UNT Libraries Government Documents Department

Solubility, viscosity and density of refrigerant/lubricant mixtures. Quarterly technical progress report, 1 January--31 March 1993

Description: This report presents results for low refrigerant concentration (70, 80, 90 and 100 weight percent lubricant) mixtures of the following fluids: CFC-12/ISO 32 naphthenic mineral oil, HCFC-22/ISO 32 naphthenic mineral oil, CFC-12/ISO 100 naphthenic mineral oil, HFC-134a/ISO 22 pentaerythritol ester mixed acid, HFC-134a/ISO 32 pentaerythritol ester mixed acid {number_sign}1, HFC-134a/ISO 68 pentaerythritol ester mixed acid, HFC-134a/ISO 100 pentaerythritol ester mixed acid, HFC-134a/ISO 32 pentaerythritol ester mixed acid {number_sign}2, HCFC-123/ISO 32 naphthenic mineral oil, HCFC-123/ISO 100 naphthenic mineral oil, HCFC-123/150 SUS alkylbenzene, HCFC-123/300 SUS alkylbenzene. These data have been reduced to engineering form and are presented in the form of a Daniel Chart. Equations are given along with statistical measures of goodness of fit.
Date: April 1, 1993
Creator: Henderson, D. R.
Partner: UNT Libraries Government Documents Department

Cygnus PFL Switch Jitter

Description: The Cygnus Dual Beam Radiographic Facility consists of two identical radiographic sources: Cygnus 1 and Cygnus 2. Each source has the following X-ray output: 1-mm diameter spot size, 4 rads at 1 m, 50-ns full-widthhalf-maximum. The diode pulse has the following electrical specifications: 2.25 MV, 60 kA, 60 ns. This Radiographic Facility is located in an underground tunnel test area at the Nevada Test Site (NTS). The sources were developed to produce high-resolution images on subcritical tests performed at NTS. Subcritical tests are single-shot, high-value events. For this application, it is desirable to maintain a high level of reproducibility in source output. The major components of the Cygnus machines are Marx generator, water-filled pulse forming line (PFL), water-filled coaxial transmission line, threecell inductive voltage adder, and rod-pinch diode. A primary source of fluctuation in Cygnus shot-to-shot performance may be jitter in breakdown of the main PFL switch, which is a “self-break” switch. The PFL switch breakdown time determines the peak PFL charging voltage, which ultimately affects the source X-ray spectrum and dose. Therefore, PFL switch jitter may contribute to shot-to-shot variation in these parameters, which are crucial to radiographic quality. In this paper we will present PFL switch jitter analysis for both Cygnus machines and present the correlation with dose. For this analysis, the PFL switch on each machine was maintained at a single gap setting, which has been used for the majority of shots at NTS. In addition the PFL switch performance for one larger switch gap setting will be examined.
Date: July 21, 2007
Creator: Mitton, C.; Corrow, G. & Henderson, D.
Partner: UNT Libraries Government Documents Department

Nuclear Analysis for Near Term Fusion Devices

Description: A Next Step Options (NSO) study was initiated to consider the logical steps that might be undertaken to restructure the U.S. Fusion Sciences Program. Most of the effort was concentrated on designing the Fusion Ignition Research Experiment (FIRE), which is in the preconceptual design phase. It utilizes 16 cryogenically cooled wedged copper TF coils with beryllium copper in the inner legs and OFHC copper in the outer legs. We provided significant contributions in the areas of neutronics, shielding and activation analyses. The design went through different changes. Early in the year 2002 the baseline design changed from a major radius of 2 m to a major radius of 2.14 m and an aspect ratio of 3.6. In addition the fusion power during the DT pulses changed from 200 MW to 150 MW. We spent significant part of the effort calculating the nuclear performance parameters for the final baseline design. While pulses producing a total of 5 TJ of DT fusion energy and 0.5 TJ of DD fusion energy were considered in the previous designs, a detailed experimental plan was developed that results in higher total fusion energy. We assessed the impact on the peak magnet insulator dose. Multi-dimensional calculations were performed also to determine the impact of plasma shape and profile on he peak radiation effects in the TF coils. We performed multi-dimensional calculations for one of the most critical diagnostics ports to assess streaming and determine the nuclear environment at the sensitive components. The radwaste level and volume was quantified for the different components of FIRE.
Date: April 2, 2007
Creator: Sawan, M.E.; Kulcinski, G.L. & Henderson, D.L.
Partner: UNT Libraries Government Documents Department