Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report April 1–June 30, 2010 (open access)

Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report April 1–June 30, 2010

Individual raw datastreams from instrumentation at the Atmospheric Radiation Measurement (ARM) Climate Research Facility fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent approximately daily to the ARM Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual datastream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998.
Date: July 9, 2010
Creator: Sisterson, D. L.
Object Type: Report
System: The UNT Digital Library
Characterization of electron microscopes with binary pseudo-random multilayer test samples (open access)

Characterization of electron microscopes with binary pseudo-random multilayer test samples

We discuss the results of SEM and TEM measurements with the BPRML test samples fabricated from a BPRML (WSi2/Si with fundamental layer thickness of 3 nm) with a Dual Beam FIB (focused ion beam)/SEM technique. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize x-ray microscopes. Corresponding work with x-ray microscopes is in progress.
Date: July 9, 2010
Creator: Yashchuk, Valeriy V; Conley, Raymond; Anderson, Erik H.; Barber, Samuel K.; Bouet, Nathalie; McKinney, Wayne R. et al.
Object Type: Article
System: The UNT Digital Library
Verification of the Defense Waste Processing Facility Process Digestion Method for the Sludge Batch 6 Qualification Sample (open access)

Verification of the Defense Waste Processing Facility Process Digestion Method for the Sludge Batch 6 Qualification Sample

For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) confirms applicability of the digestion method to be used by the DWPF lab for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) receipt samples and SRAT product process control samples.1 DWPF SRAT samples are typically dissolved using a room temperature HF-HNO3 acid dissolution (i.e., DWPF Cold Chem (CC) Method, see DWPF Procedure SW4-15.201) and then analyzed by inductively coupled plasma - atomic emission spectroscopy (ICPAES). In addition to the CC method confirmation, the DWPF lab's mercury (Hg) digestion method was also evaluated for applicability to SB6 (see DWPF procedure 'Mercury System Operating Manual', Manual: SW4-15.204. Section 6.1, Revision 5, Effective date: 12-04-03). This report contains the results and comparison of data generated from performing the Aqua Regia (AR), Sodium Peroxide/Hydroxide Fusion (PF) and DWPF Cold Chem (CC) method digestion of Sludge Batch 6 (SB6) SRAT Receipt and SB6 SRAT Product samples. For validation of the DWPF lab's Hg method, only SRAT receipt material was used and compared to AR digestion results. The SB6 SRAT Receipt and SB6 SRAT Product samples were prepared in the SRNL Shielded Cells, and the …
Date: June 9, 2010
Creator: Click, D.; Jones, M. & Edwards, T.
Object Type: Report
System: The UNT Digital Library
X-ray optics metrology limited by random noise, instrumental drifts, and systematic errors (open access)

X-ray optics metrology limited by random noise, instrumental drifts, and systematic errors

Continuous, large-scale efforts to improve and develop third- and forth-generation synchrotron radiation light sources for unprecedented high-brightness, low emittance, and coherent x-ray beams demand diffracting and reflecting x-ray optics suitable for micro- and nano-focusing, brightness preservation, and super high resolution. One of the major impediments for development of x-ray optics with the required beamline performance comes from the inadequate present level of optical and at-wavelength metrology and insufficient integration of the metrology into the fabrication process and into beamlines. Based on our experience at the ALS Optical Metrology Laboratory, we review the experimental methods and techniques that allow us to mitigate significant optical metrology problems related to random, systematic, and drift errors with super-high-quality x-ray optics. Measurement errors below 0.2 mu rad have become routine. We present recent results from the ALS of temperature stabilized nano-focusing optics and dedicated at-wavelength metrology. The international effort to develop a next generation Optical Slope Measuring System (OSMS) to address these problems is also discussed. Finally, we analyze the remaining obstacles to further improvement of beamline x-ray optics and dedicated metrology, and highlight the ways we see to overcome the problems.
Date: July 9, 2010
Creator: Yashchuk, Valeriy V.; Anderson, Erik H.; Barber, Samuel K.; Cambie, Rossana; Celestre, Richard; Conley, Raymond et al.
Object Type: Article
System: The UNT Digital Library
Climate implications of carbonaceous aerosols:  An aerosol microphysical study using the GISS/MATRIX climate model (open access)

Climate implications of carbonaceous aerosols: An aerosol microphysical study using the GISS/MATRIX climate model

Recently, attention has been drawn towards black carbon aerosols as a likely short-term climate warming mitigation candidate. However the global and regional impacts of the direct, cloud-indirect and semi-direct forcing effects are highly uncertain, due to the complex nature of aerosol evolution and its climate interactions. Black carbon is directly released as particle into the atmosphere, but then interacts with other gases and particles through condensation and coagulation processes leading to further aerosol growth, aging and internal mixing. A detailed aerosol microphysical scheme, MATRIX, embedded within the global GISS modelE includes the above processes that determine the lifecycle and climate impact of aerosols. This study presents a quantitative assessment of the impact of microphysical processes involving black carbon, such as emission size distributions and optical properties on aerosol cloud activation and radiative forcing. Our best estimate for net direct and indirect aerosol radiative forcing change is -0.56 W/m{sup 2} between 1750 and 2000. However, the direct and indirect aerosol effects are very sensitive to the black and organic carbon size distribution and consequential mixing state. The net radiative forcing change can vary between -0.32 to -0.75 W/m{sup 2} depending on these carbonaceous particle properties. Assuming that sulfates, nitrates and secondary …
Date: April 9, 2010
Creator: Bauer, Susanne E.; Menon, Surabi; Koch, Dorothy; Bond, Tami & Tsigaridis, Kostas
Object Type: Article
System: The UNT Digital Library
Development of a new generation of optical slope measuring profiler (open access)

Development of a new generation of optical slope measuring profiler

We overview the results of a broad US collaboration, including all DOE synchrotron labs (ALS, APS, BNL, NSLS-II, LLNL, LCLS), major industrial vendors of x-ray optics (InSync, Inc., SSG Precision Optronics-Tinsley, Inc., Optimax Systems, Inc.), and with active participation of HBZ-BESSY-II optics group, on development of a new generation slope measuring profiler -- the optical slope measuring system (OSMS). The desired surface slope measurement accuracy of the instrument is<50 nrad (absolute) that is adequate to the current and foreseeable future needs for metrology of x-ray optics for the next generation of light sources.
Date: July 9, 2010
Creator: Yashchuk, Valeriy V.; Takacs, Peter Z.; McKinney, Wayne R. & Assoufid, Lahsen
Object Type: Article
System: The UNT Digital Library
Implications of HARP Results for the Energy of the Proton Driver for a Neutrino Factory and Muon Collider (open access)

Implications of HARP Results for the Energy of the Proton Driver for a Neutrino Factory and Muon Collider

Cross-section data from the HARP experiment for pion production by protons from a tantalum target have been convoluted with the acceptance of the front-end channel for the proposed neutrino factory or muon collider and integrated over the full phase space measured by HARP, to determine the beam-energy dependence of the muon yield. This permits a determination of the optimal beam energy for the proton driver for these projects. The cross-section data are corrected for the beam-energy dependent 'amplification' due to the development of hadronic showers in a thick target. The conclusion is that, for constant beam power, the yield is maximum for a beam energy of about 7 GeV, but it is within 10% of this maximum for 4 < T{sub beam} < 11 GeV, and within 20% of the maximum for T{sub beam} as low as 2 GeV. This result is insensitive to which of the two HARP groups results are used, and to which pion generator is used to compute the thick target effects.
Date: June 9, 2010
Creator: Strait, J.; Mokhov, N. V. & Striganov, S. I.
Object Type: Article
System: The UNT Digital Library
Optimization Studies for Radiation Shielding of a Superconducting RF Cavity Test Facility (open access)

Optimization Studies for Radiation Shielding of a Superconducting RF Cavity Test Facility

Test facilities for high-gradient superconducting RF cavities must be shielded for particle radiation, which is generated by field emitted electrons in the cavities. A major challenge for the shielding design is associated with uncertainty in modeling the field emission. In this work, a semi-empirical method that allows us to predict the intensity of the generated field emission is described. Spatial, angular and energy distributions of the generated radiation are calculated with the FISHPACT code. The Monte Carlo code MARS15 is used for modeling the radiation transport in matter. The detailed distributions of the generated field emission are used for studies with 9-cell 1.3 GHz superconducting RF cavities in the Fermilab Vertical Cavity Test Facility. This approach allows us to minimize the amount of shielding inside cryostat which is an essential operational feature.
Date: July 9, 2010
Creator: Ginsburg, Camille M. & Rakhno, Igor
Object Type: Article
System: The UNT Digital Library
Tumor Engineering: The Other Face of Tissue Engineering (open access)

Tumor Engineering: The Other Face of Tissue Engineering

Advances in tissue engineering have been accomplished for years by employing biomimetic strategies to provide cells with aspects of their original microenvironment necessary to reconstitute a unit of both form and function for a given tissue.We believe that the most critical hallmark of cancer is loss of integration of architecture and function; thus, it stands to reason that similar strategies could be employed to understand tumor biology. In this commentary, we discuss work contributed by Fischbach-Teschl and colleagues to this special issue of Tissue Engineering in the context of 'tumor engineering', that is, the construction of complex cell culture models that recapitulate aspects of the in vivo tumor microenvironment to study the dynamics of tumor development, progression, and therapy on multiple scales. We provide examples of fundamental questions that could be answered by developing such models, and encourage the continued collaboration between physical scientists and life scientists not only for regenerative purposes, but also to unravel the complexity that is the tumor microenvironment. In 1993, Vacanti and Langer cast a spotlight on the growing gap between patients in need of organ transplants and the amount of available donor organs; they reaffirmed that tissue engineering could eventually address this problem by …
Date: March 9, 2010
Creator: Ghajar, Cyrus M & Bissell, Mina J
Object Type: Book
System: The UNT Digital Library
New Classes of Quasi-helically Symmetric Stellarators (open access)

New Classes of Quasi-helically Symmetric Stellarators

New classes of quasi-helically symmetric stellarators with aspect ratios ≤ 10 have been found which are stable to the perturbation of magnetohydrodynamic modes at plasma pressures of practical interest. These configurations have large rotational transform and good quality of flux surfaces. Characteristics of some selected examples are discussed in detail. The feasibility of using modular coils for these stellarators has been investigated. It is shown that practical designs for modular coils can be achieved.
Date: August 9, 2010
Creator: Ku, L. P.
Object Type: Report
System: The UNT Digital Library
Nanograting-based compact VUV spectrometer and beam profiler for in-situ characterization of high-order harmonic generation light sources (open access)

Nanograting-based compact VUV spectrometer and beam profiler for in-situ characterization of high-order harmonic generation light sources

A compact, versatile device for VUV beam characterization is presented. It combines the functionalities of a VUV spectrometer and a VUV beam profiler in one unit and is entirely supported by a standard DN200 CF flange. The spectrometer employs a silicon nitride transmission nanograting in combination with a micro-channel plate based imaging detector. This enables the simultaneous recording of wavelengths ranging from 10 nm to 80 nm with a resolution of 0.25 nm to 0.13 nm. Spatial beam profiles with diameters up to 10 mm are imaged with 0.1 mm resolution. The setup is equipped with an in-vacuum translation stage that allows for in situ switching between the spectrometer and beam profiler modes and for moving the setup out of the beam. The simple, robust design of the device is well suited for non-intrusive routine characterization of emerging laboratory- and accelerator-based VUV light sources. Operation of the device is demonstrated by characterizing the output of a femtosecond high-order harmonic generation light source.
Date: July 9, 2010
Creator: Kornilov, Oleg; Wilcox, Russell & Gessner, Oliver
Object Type: Article
System: The UNT Digital Library
Alternate Materials in Design of Radioactive Material Packages (open access)

Alternate Materials in Design of Radioactive Material Packages

This paper presents a summary of design and testing of material and composites for use in radioactive material packages. These materials provide thermal protection and provide structural integrity and energy absorption to the package during normal and hypothetical accident condition events as required by Title 10 Part 71 of the Code of Federal Regulations. Testing of packages comprising these materials is summarized.
Date: July 9, 2010
Creator: Blanton, P. & Eberl, K.
Object Type: Article
System: The UNT Digital Library
Energy Proportionality for Disk Storage Using Replication (open access)

Energy Proportionality for Disk Storage Using Replication

Energy saving has become a crucial concern in datacenters as several reports predict that the anticipated energy costs over a three year period will exceed hardware acquisition. In particular, saving energy for storage is of major importance as storage devices (and cooling them off) may contribute over 25 percent of the total energy consumed in a datacenter. Recent work introduced the concept of energy proportionality and argued that it is a more relevant metric than just energy saving as it takes into account the tradeoff between energy consumption and performance. In this paper, we present a novel approach, called FREP (Fractional Replication for Energy Proportionality), for energy management in large datacenters. FREP includes areplication strategy and basic functions to enable flexible energy management. Specifically, our method provides performance guarantees by adaptively controlling the power states of a group of disks based on observed and predicted workloads. Our experiments, using a set of real and synthetic traces, show that FREP dramatically reduces energy requirements with a minimal response time penalty.
Date: September 9, 2010
Creator: Kim, Jinoh & Rotem, Doron
Object Type: Report
System: The UNT Digital Library
Major Effects in the Thermodynamics of Detonation Products: Phase Segregation versus Ionic Dissociation (open access)

Major Effects in the Thermodynamics of Detonation Products: Phase Segregation versus Ionic Dissociation

Water (H{sub 2}O) and nitrogen (N{sub 2}) are major detonation products of high explosives and it has long been conjectured that they may phase segregate at high enough temperatures and pressures to influence detonation properties of common explosives. We analyze the phase diagram of H{sub 2}O-N{sub 2} mixtures using a thermodynamic theory for polar-nonpolar mixtures and find that phase segregation is unlikely to occur above approximately 1600K. Therefore, H{sub 2}O-N{sub 2} immiscibility is not likely to be relevant for detonation predictions. We propose instead that the high pressure ionic dissociation of water plays an important role in detonation, and model it using a new ionic thermodynamics. We employ this model in chemical equilibrium calculations of standard high explosives, e.g. PETN, HMX and RDX, and find that it performs very well under a wide range of conditions. Thus, although it may require further development, it is likely that explicitly ionic thermodynamics will become a standard tool for explosives modeling.
Date: March 9, 2010
Creator: Bastea, S & Fried, L E
Object Type: Article
System: The UNT Digital Library
PERFORMANCE OF A CONTAINMENT VESSEL CLOSURE FOR RADIOACTIVE GAS CONTENTS (open access)

PERFORMANCE OF A CONTAINMENT VESSEL CLOSURE FOR RADIOACTIVE GAS CONTENTS

This paper presents a summary of the design and testing of the containment vessel closure for the Bulk Tritium Shipping Package (BTSP). This package is a replacement for a package that has been used to ship tritium in a variety of content configurations and forms since the early 1970s. The containment vessel closure incorporates features specifically designed for the containment of tritium when subjected to the normal and hypothetical conditions required of Type B radioactive material shipping Packages. The paper discusses functional performance of the containment vessel closure of the BTSP prototype packages and separate testing that evaluated the performance of the metallic C-Rings used in a mock BTSP closure.
Date: July 9, 2010
Creator: Blanton, P. & Eberl, K.
Object Type: Article
System: The UNT Digital Library
GLOBAL MONITORING OF URANIUM HEXIFLORIDE CYLINDERS NEXT STEPS IN DEVELOPMENT OF AN ACTION PLAN (open access)

GLOBAL MONITORING OF URANIUM HEXIFLORIDE CYLINDERS NEXT STEPS IN DEVELOPMENT OF AN ACTION PLAN

Over 40 industrial facilities world-wide use standardized uranium hexafluoride (UF{sub 6}) cylinders for transport, storage and in-process receiving in support of uranium conversion, enrichment and fuel fabrication processes. UF{sub 6} is processed and stored in the cylinders, with over 50,000 tU of UF{sub 6} transported each year in these International Organization for Standardization (ISO) qualified containers. Although each cylinder is manufactured to an ISO standard that calls for a nameplate with the manufacturer's identification number (ID) and the owner's serial number engraved on it, these can be quite small and difficult to read. Recognizing that each facility seems to use a different ID, a cylinder can have several different numbers recorded on it by means of metal plates, sticky labels, paint or even marker pen as it travels among facilities around the world. The idea of monitoring movements of UF{sub 6} cylinders throughout the global uranium fuel cycle has become a significant issue among industrial and safeguarding stakeholders. Global monitoring would provide the locations, movements, and uses of cylinders in commercial nuclear transport around the world, improving the efficiency of industrial operations while increasing the assurance that growing nuclear commerce does not result in the loss or misuse of cylinders. …
Date: June 9, 2010
Creator: Hanks, D.
Object Type: Article
System: The UNT Digital Library
End of Enrichment Reconstruction (open access)

End of Enrichment Reconstruction

The age and composition of special nuclear material (SNM) offers a great deal of forensic information; e.g., likely producer or country of origin. Nuclear materials (nuclides) decay at different rates, often in a chain fashion; therefore, the composition of the nuclides changes over time. Trace nuclides in special nuclear material often carry more information regarding age and original composition, but trace nuclides can be easily lost in 'approximations.' Current decay calculation technology is based on a matrix Taylor approximation that is imprecise in nature and time-consuming to compute. Better computational technology for decay calculation and age estimation is needed. This project offers better Nuclear Forensics technology solutions for these needs.
Date: June 9, 2010
Creator: Yuan, Ding
Object Type: Article
System: The UNT Digital Library
Hydrogen Delivey Infrastructure Option Analysis (open access)

Hydrogen Delivey Infrastructure Option Analysis

This report summarizes an evaluation of various hydrogen delivery options
Date: May 9, 2010
Creator: Chen, Tan-Ping
Object Type: Report
System: The UNT Digital Library
Strike Point Control for the National Spherical Torus Experiment (NSTX) (open access)

Strike Point Control for the National Spherical Torus Experiment (NSTX)

This paper presents the first control algorithm for the inner and outer strike point position for a Spherical Torus (ST) fusion experiment and the performance analysis of the controller. A liquid lithium divertor (LLD) will be installed on NSTX which is believed to provide better pumping than lithium coatings on carbon PFCs. The shape of the plasma dictates the pumping rate of the lithium by channeling the plasma to LLD, where strike point location is the most important shape parameter. Simulations show that the density reduction depends on the proximity of strike point to LLD. Experiments were performed to study the dynamics of the strike point, design a new controller to change the location of the strike point to desired location and stabilize it. The most effective PF coils in changing inner and outer strike points were identified using equilibrium code. The PF coil inputs were changed in a step fashion between various set points and the step response of the strike point position was obtained. From the analysis of the step responses, PID controllers for the strike points were obtained and the controller was tuned experimentally for better performance. The strike controller was extended to include the outer-strike point …
Date: July 9, 2010
Creator: Kolemen, E.; Gates, D. A.; Rowley, C. W.; Kasdin, N. J.; Kallman, J.; Gerhardt, S. et al.
Object Type: Report
System: The UNT Digital Library
An imaging proton spectrometer for short-pulse laser plasma experiments (open access)

An imaging proton spectrometer for short-pulse laser plasma experiments

Ultra intense short pulse laser pulses incident on solid targets can generate energetic protons. In additions to their potentially important applications such as in cancer treatments and proton fast ignition, these protons are essential to understand the complex physics of intense laser plasma interaction. To better understand these laser-produced protons, we designed and constructed a novel, spatially imaging proton spectrometer that will not only provide at high-resolution the energy distribution, but also the protons angular characteristics. The information obtained from this spectrometer compliments those from other methods using radiochromic film packs, CR39 films and other protons spectrometers. The basic characterizations and example data from this diagnostics will be presented. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, as part of the Cimarron project funded by LDRD-09SI11.
Date: February 9, 2010
Creator: Chen, H.; Hazi, A.; van Maren, R.; Chen, S.; Fuchs, J.; Gauthier, M. et al.
Object Type: Article
System: The UNT Digital Library
Electrochemical hydrogen Storage Systems (open access)

Electrochemical hydrogen Storage Systems

As the global need for energy increases, scientists and engineers have found a possible solution by using hydrogen to power our world. Although hydrogen can be combusted as a fuel, it is considered an energy carrier for use in fuel cells wherein it is consumed (oxidized) without the production of greenhouse gases and produces electrical energy with high efficiency. Chemical storage of hydrogen involves release of hydrogen in a controlled manner from materials in which the hydrogen is covalently bound. Sodium borohydride and aminoborane are two materials given consideration as chemical hydrogen storage materials by the US Department of Energy. A very significant barrier to adoption of these materials as hydrogen carriers is their regeneration from 'spent fuel,' i.e., the material remaining after discharge of hydrogen. The U.S. Department of Energy (DOE) formed a Center of Excellence for Chemical Hydrogen Storage, and this work stems from that project. The DOE has identified boron hydrides as being the main compounds of interest as hydrogen storage materials. The various boron hydrides are then oxidized to release their hydrogen, thereby forming a 'spent fuel' in the form of a lower boron hydride or even a boron oxide. The ultimate goal of this project …
Date: August 9, 2010
Creator: Macdonald, Dr. Digby
Object Type: Report
System: The UNT Digital Library
On The Anomalous Fast Ion Energy Diffusion in Toroidal Plasmas Due to Cavity Modes (open access)

On The Anomalous Fast Ion Energy Diffusion in Toroidal Plasmas Due to Cavity Modes

An enormous wave-particle diffusion coefficient along paths suitable for alpha channeling had been deduced in mode converted ion Bernstein wave experiments on Tokamak Fusion Test Reactor (TFTR) the only plausible explanation advanced for such a large diffusion coefficient was the excitation of internal cavity modes which induce particle diffusion along identical diffusion paths, but at much higher rates. Although such a mode was conjectured, it was never observed. However, recent detailed observations of high frequency compressional Alfven eigenmodes (CAEs) on the National Spherical torus Experiment (NSTX) indirectly support the existence of the related conjectured modes on TFTR. The eigenmodes responsible for the high frequency magnetic activity can be identified as CAEs through the polarization of the observed magnetic field oscillations in NSTX and through a comparison with the theoretically derived freuency dispersion relation. Here, we show how these recent observations of high frequency CAEs lend support to this explanation of the long-standing puzzle of anomalous fast ion energy diffusion on TFTR. The support of the conjecure that these internal modes could have caused the remarkable ion energy diffusion on TFTR carries significant and favorable implications for the possibilities in achieving the alpha channeling effect with small injected power in a …
Date: March 9, 2010
Creator: Gorelenkov, N. N.; Fisch, N. J. & Fredrickson, E.
Object Type: Report
System: The UNT Digital Library
Room Temperature Magnetic Barrier Layers in Magnetic Tunnel Junctions (open access)

Room Temperature Magnetic Barrier Layers in Magnetic Tunnel Junctions

We investigate the spin transport and interfacial magnetism of magnetic tunnel junctions with highly spin polarized LSMO and Fe3O4 electrodes and a ferrimagnetic NiFe2O4 (NFO) barrier layer. The spin dependent transport can be understood in terms of magnon-assisted spin dependent tunneling where the magnons are excited in the barrier layer itself. The NFO/Fe3O4 interface displays strong magnetic coupling, while the LSMO/NFO interface exhibits clear decoupling as determined by a combination of X-ray absorption spectroscopy and X-ray magnetic circular dichroism. This decoupling allows for distinct parallel and antiparallel electrode states in this all-magnetic trilayer. The spin transport of these devices, dominated by the NFO barrier layer magnetism, leads to a symmetric bias dependence of the junction magnetoresistance at all temperatures.
Date: March 9, 2010
Creator: Nelson-Cheeseman, B. B.; Wong, F. J.; Chopdekar, R. V.; Arenholz, E. & Suzuki, Y.
Object Type: Article
System: The UNT Digital Library
DDES and IDDES of Tandem Cylinders. (open access)

DDES and IDDES of Tandem Cylinders.

The paper presents an overview of the authors contribution to the BANC-I Workshop on the flow past tandem cylinders (Category 2). It includes an outline of the simulation approaches, numerics, and grid used, the major results of the simulations, their comparison with available experimental data, and some preliminary conclusions. The effect of varying the spanwise period in the simulations is strong for some quantities, and not others.
Date: September 9, 2010
Creator: Balakrishnan, R.; Garbaruk, A.; Shur, M.; Strelets, M.; Spalart, P.; Russia, New Technologies and Services - et al.
Object Type: Report
System: The UNT Digital Library