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Commercialization of Turbulent Combustion Code CREBCOM for Chemical Industry Safety

Description: This program developed the Kurchatov Institute’s CREBCOM (CRiteria and Experimentally Based COMbustion) code to the point where it could be commercialized and marketed for the special applications described above, as well as for general purpose combustion calculations. The CREBCOM code uses a different approach to model the explosion phenomenon. The code models, with full 3D gas dynamics, the development of an explosion in three characteristics regimes: a) slow flames, b) fast flames, and c) detonation. The transition from one regime to another is governed by a set of empirical criteria and correlations. As part of the commercialization, the code was validated with the use of experimental data. The experimental data covered a range of thermodynamic initial conditions and apparatus scale. Proprietary experimental data were provided to the Kurchatov Institute by the DuPont for this purpose. The flame acceleration and detonation data was obtained from experiments in methane and oxygen enriched air mixtures carried out in two vessels with diameters of 20 and 27 cm. The experimental data covers a wide spectrum of initial temperature (20-525C) and pressure (1-3 atm). As part of this program, the Kurchatov Institute performed experiments in a 52 cm vessel in mixtures of methane-air at room temperature and pressure to be used in the validation of the code. The objective of these tests was to obtain frame acceleration data at a scale close to that found in actual industrial processes. BNL was responsible for managing the DOE/IPP portion of the program, and for satisfying DOE reporting requirements. BNL also participated in an independent assessment of the CREBOM code. DuPont provided proprietary experimental data to the Kurchatov Institute on flame acceleration and detonation in high temperature methane and oxygen enriched air mixtures in addition to the matching fund. In addition, DuPont also supplied to KI instrumentation for ...
Date: June 30, 2007
Creator: Rohatgi, Upendra
Partner: UNT Libraries Government Documents Department

PREDICTION OF LOW-CYCLE FATIGUE-LIFE BY ACOUSTIC EMISSION. PART 1: 2024-T3 ALUMINUM ALLOY PART 2: ALCLAD 7075-T6/ ALUMINUM ALLOY

Description: Low-cycle fatigue tests were conducted by tension-compression until rupture, on a 2024-T3 aluminum alloy sheet. Initial crack sizes and orientations in the fatigue specimens were found to be randomly distributed. Acoustic emission was continuously monitored during the tests. Every few hundred cycles, the acoustic signal having the highest peak-amplitude, was recorded as an extremal event for the elapsed period. This high peak-amplitude is related to a fast crack propagation rate through a phenomenological relationship. The extremal peakamplitudes are shown by an ordered statistics treatment, to be extremally distributed. The statistical treatment enables the prediction of the number of cycles left until failure. Predictions performed a-posteriori based on results gained early in each fatigue test are in good agreement with actual fatigue lives. The amplitude distribution analysis of the acoustic signals emitted during cyclic stress appears to be a promising nondestructive method of predicting fatigue life.
Date: May 1, 1980
Creator: Baram, J. & Rosen, M.
Partner: UNT Libraries Government Documents Department

Quarterly Summary Report April-June 1978 Process for Cleaning and Removal of Sulfur Compounds From Low Btu Gases

Description: In this phase of work the Process Development Unit (PDU) is to be remodeled by incorporation of appropriate subsystems to permit operation in continuous process mode. The PDU will be operated for a period of time sufficient to demonstrate process viability.
Date: July 1, 1978
Partner: UNT Libraries Government Documents Department

Wave transmission and mooring-force characteristics of pipe-tire floating breakwaters

Description: The results are presented of a series of prototype scale tests of a floating breakwater that incorporates massive cylindrical members (steel or concrete pipes, telephone poles, etc.) in a matrix of scrap truck or automobile tires, referred to as the Pipe-Tire Breakwater (PT-Breakwater). Tests were conducted in the large wave tank at the US Army Coastal Engineering Research Center (CERC). Breakwater modules were preassembled at SUNY in Buffalo, New York, and then transported to CERC by truck, where final assembly on location was again performed by SUNY personnel. Wave-tank tests were conducted jointly by CERC and SUNY personnel. A series of wave-tank experiments and mooring system load-deflection tests were performed, and are described. Wave-transmission and mooring-load characteristics, based on 402 separate tests, were established and are reported. (LCL)
Date: October 1, 1980
Creator: Harms, Volker W. & Westerink, Joannes J.
Partner: UNT Libraries Government Documents Department

AN EXPERIMENTAL STUDY OF THE FLOW FIELD OF A TWO DIMENSIONAL PREMIXED TURBULENT FLAME

Description: A turbulent reacting shear layer in a premixed propane/air flow has been studied in a two dimensional combustor, with the flame stabilized behind a rearward facing streamlined step. Spark shadowgraphs show that in the range of velocities (7.5 to 22.5 m/sec corresponding to Reynolds numbers of .5 x 10{sup 4} cm{sup -1} to 1. 5 x 10{sup 4} cm{sup -1} ) and equivalence ratios (0.4 to 0.7) studied, the mixing layer is dominated by Brown~ Roshko type large coherent structures in both reacting and nonreacting flows. High speed schlieren movies show that these eddies are convected downstream and increase their size and spacing by combustion and coalescence with neighboring eddies. Tracing individual eddies shows, in the reacting shear layer, that, on the average, eddies accelerate as they move downstream with the highest acceleration close to the origin of the shear layer. Combustion is confined to these large structures which develop as a result of vortical action of the shear flow. On the average, the reacting eddies have a lower growth rate than nonreacting eddies. A turbulent boundary layer created by means of a tripping wire upstream of the edge of the step virtually eliminates the large coherent structures in the shear layer, while for the case in which the wire could not trigger the transition to turbulence, the large coherent structures dominated the reacting and nonreacting flows.
Date: April 1, 1980
Creator: Ganji, A.R. & Sawyer, R.F.
Partner: UNT Libraries Government Documents Department

THERMOPHORETIC VELOCITY OF LARGE AEROSOL PARTICLES

Description: The velocity of thermal repulsion of large aerosol particles has been calculated by others by equating the thermal force on a stationary partlcle to the Stokes-Cunningham viscous force. This procedure is theoretically unsound because the boundary conditions employed in the viscous force equation are erroneous when the particle moves in a thermal gradient. In the current study these difficulties have been circumvented by rederiving the thermal force equation, allowing for a relative velocity between the particle and the gas stream. The velocity of motion is then calculated by setting the net force on the particle equal to zero. The velocity obtained by this more realistic approach agrees with that calculated by the former method, which is surprising in view of the incorrect boundary conditions employed in the former method. Investigation of the drag force equation shows that the thermal force and the viscous force are exerted independently of each other, which explains this unexpected agreement, The range of applicability of the analysis is explored by comparison with available experimental data,
Date: November 1, 1965
Creator: Postma, A. K.
Partner: UNT Libraries Government Documents Department

PHYSICAL EFFECTS OF THE HANFORD WINDSTORMS OF JANUARY 11, 1972 AND JANUARY 21, 1972

Description: The windstorm of January 11 caused a minor amount of damage to the Hanford Reservation and Hanford vicinity. Damage sustained to Hanford Reservation structures (roofing, flashing, fences, windows) was approximately $20,000. One building did receive structural damage to roof members. Evidence that wind pressures did not reach 30 lb/ft{sup 2} during the January 11 windstorm was provided in the fact that specially designed exterior wall panels did not fail. These panels were designed and carefully proof-tested to insure that they would fail at a loading of 30 lb/ft{sup 2} as a requirement of structural safety in the original design-construction program in 1952-1954. There was one power outage on the Hanford Reservation due to the January 11 windstorm (Rattlesnake Mountain Observatory). Damage to power lines and electrical facilities amounted to about $1600. Damage to structures in the Hanford vicinity (excluding the Hanford Reservation) from the January 11 windstorm was estimated to cost $13,000. This does not include damage to private residences, etc., which has been estimated by others to be near $250,000. Power line damage in the Hanford vicinity amounted to about $80,000, of which $60,000 was accounted for in the loss of four transmission towers in the tie-line between Priest Rapids and Wanapum Dams. The January 21 windstorm, which struck Toppenish, Washington, was a straight-wind of the catabatic foehn type and not a tornado-type wind as described in newspaper accounts. No funnel cloud was associated with this windstorm. The maximum gust was about 85 mph at 30 ft above the ground. Cost estimates of damage in Toppenish were not available. There were no power outages or structural damage on the Hanford Reservation from the January 21 windstorm. Total damage to the Hanford Reservation from the two windstorms was estimated to be about $22,500.
Date: June 1, 1972
Creator: Henager, C. H. & Fuquay, J. J.
Partner: UNT Libraries Government Documents Department

Computational fluid dynamic modeling of fluidized-bed polymerization reactors

Description: Polyethylene is one of the most widely used plastics, and over 60 million tons are produced worldwide every year. Polyethylene is obtained by the catalytic polymerization of ethylene in gas and liquid phase reactors. The gas phase processes are more advantageous, and use fluidized-bed reactors for production of polyethylene. Since they operate so close to the melting point of the polymer, agglomeration is an operational concern in all slurry and gas polymerization processes. Electrostatics and hot spot formation are the main factors that contribute to agglomeration in gas-phase processes. Electrostatic charges in gas phase polymerization fluidized bed reactors are known to influence the bed hydrodynamics, particle elutriation, bubble size, bubble shape etc. Accumulation of electrostatic charges in the fluidized-bed can lead to operational issues. In this work a first-principles electrostatic model is developed and coupled with a multi-fluid computational fluid dynamic (CFD) model to understand the effect of electrostatics on the dynamics of a fluidized-bed. The multi-fluid CFD model for gas-particle flow is based on the kinetic theory of granular flows closures. The electrostatic model is developed based on a fixed, size-dependent charge for each type of particle (catalyst, polymer, polymer fines) phase. The combined CFD model is first verified using simple test cases, validated with experiments and applied to a pilot-scale polymerization fluidized-bed reactor. The CFD model reproduced qualitative trends in particle segregation and entrainment due to electrostatic charges observed in experiments. For the scale up of fluidized bed reactor, filtered models are developed and implemented on pilot scale reactor.
Date: November 2, 2012
Creator: Rokkam, Ram
Partner: UNT Libraries Government Documents Department

LESSONS LEARNED - STARTUP AND TRANSITION TO OPERATIONS AT THE 200 WEST PUMP AND TREAT FACILITY

Description: This document lists key Lessons Learned from the Startup Team for the 200 West Pump and Treat Facility Project. The Startup Team on this Project was an integrated, multi-discipline team whose scope was Construction Acceptance Testing (CAT), functional Acceptance Testing Procedures (ATP), and procedure development and implementation. Both maintenance and operations procedures were developed. Included in the operations procedures were the process unit operations. In addition, a training and qualification program was also part of the scope.
Date: October 3, 2012
Creator: DE, FINK; GG, BERGQUIST & SP, BURKE
Partner: UNT Libraries Government Documents Department

Laser Fusion: The First Ten Years 1962-1972

Description: This account of the beginning of the program on laser fusion at Livermore in 1962, and its subsequent development during the decade ending in 1972, was originally prepared as a contribution to the January 1991 symposium 'Achievements in Physics' honoring Professor Keith Brueckner upon his retirement from the University of San Diego at La Jolla. It is a personal recollection of work at Livermore from my vantage point as its scientific leader, and of events elsewhere that I thought significant. This period was one of rapid growth in which the technology of high-power short-pulse lasers needed to drive the implosion of thermonuclear fuel to the temperature and density needed for ignition was developed, and in which the physics of the interaction of intense light with plasmas was explored both theoretically and experimentally.
Date: June 25, 2004
Creator: Kidder, R. E.
Partner: UNT Libraries Government Documents Department

Effective Specific Impulse of a Pulsed Rocket Engine

Description: The specific impulse achieved in a pulsed rocket engine augmented with a fissioning nuclear bomb could be greater than that of any continuous flow engine. To a certain extent, this increase in specific impulse would be obtained at the expense of motor weight and average thrust. This paper considers the first of these limitations, motor weight, and estimates the highest effective specific impulse to be expected from a nuclear-pulsed rocket motor with respect to the weight of the motor.
Date: May 5, 1965
Creator: Platt, E. A. & Hanner, D. W.
Partner: UNT Libraries Government Documents Department

NUMERICAL MODELING OF TURBULENT FLOW IN A COMBUSTION TUNNEL

Description: A numerical technique for the analysis of turbulent flow associated with combustion is presented, The technique utilizes Chorin's RVM (Random Vortex Method), an algorithm capable of tracing the action of elementary turbulent eddies and their cumulative effects without imposing any restriction upon their motion. In the past RVM has been used with success to treat non-reacting turbulent flows, revealing, in particular, the mechanics of large scale flow patterns, the so-called coherent structures. Introduced here is a flame propagation algorithm, also developed by Chorin, in conjunction with volume sources modeling the mechanical effects of the exothermic process of combustion. As an illustration of its use, the technique is applied to flow in a combustion tunnel where the flame is stabilized by a back-facing step. Solutions for both non-reacting and reacting flow fields are obtained, under the restriction of a set of most stringent idealizations, mimicking nonetheless quite satisfactorily the essential features of turbulent combustion in a lean propane-air mixture that were observed in the laboratory by means of high speed schlieren cinematography.
Date: September 1, 1980
Creator: Ghoniem, A. F.; Chorin, A. J. & Oppenheim, A. K.
Partner: UNT Libraries Government Documents Department

GLIMM'S METHOD FOR GAS DYNAMICS

Description: We investigate Glimm's method, a method for constructing approximate solutions to systems of hyperbolic conservation laws in one space variable by sampling explicit wave solutions. It is extended to several space variables by operator splitting. We consider two functional problems. 1) We propose a highly accurate form of the sampling procedure, in one space variable, based on the van der Corput sampling sequence. We test the improved sampling procedure numerically in the case of inviscid compressible flow in one space dimension and find that it gives high resolution results both in the smooth parts of the solution, as well as the discontinuities. 2) We investigate the operator splitting procedure by means of which the multidimensional method is constructed. An 0(1) error stemming from the use of this procedure near shocks oblique to the spatial grid is analyzed numerically in the case of the equations for inviscid compressible flow in two space dimensions. We present a hybrid method which eliminates this error, consisting of Glimm's method, used in continuous parts of the flow, and the nonlinear Godunov's method, used in regions where large pressure jumps are generated. The resulting method is seen to be a substantial improvement over either of the component methods for multidimensional calculations.
Date: July 1, 1980
Creator: Colella, Phillip
Partner: UNT Libraries Government Documents Department

Final Report for The University of Texas at Arlington Optical Medical Imaging Section of Advanced Imaging Research Center

Description: The goal of this project was to create state-of-the-art optical medical imaging laboratories for the Biomedical Engineering faculty and student researchers of the University of Texas at Arlington (UTA) on the campus of the University of Texas Southwestern Medical Center (UTSW). This has been successfully achieved. These laboratories provide an unprecedented opportunity for the bioengineers (from UTA) to bring about new breakthroughs in medical imaging using optics. Specifically, three major laboratories have been successfully established and state-of-the-art scientific instruments have been placed in the labs. As a result of this grant, numerous journal and conference publications have been generated, patents for new inventions have been filed and received, and many additional grants for the continuation of the research has been received.
Date: February 26, 2013
Creator: Behbehani, Khosrow
Partner: UNT Libraries Government Documents Department

Evaluation of ASME Section XI Reference Level Sensitivity for Initiation of Ultrasonic Inspection Examination

Description: This report evaluates the change in inspection sensitivity resulting in major changes of ASME Boiler and Pressure Vessel Code Section XI between 1974 and 1977 Editions. It was found that the inspection sensitivity resulting from requirements of the 1977 Edition of Section XI were not adequate to detect minimum flaws referenced by same Code.
Date: April 1, 1981
Creator: Taylor, T. T. & Selby, G. P.
Partner: UNT Libraries Government Documents Department

Advanced Refrigerant-Based Cooling Technologies for Information and Communication Infrastructure (ARCTIC)

Description: Faster, more powerful and dense computing hardware generates significant heat and imposes considerable data center cooling requirements. Traditional computer room air conditioning (CRAC) cooling methods are proving increasingly cost-ineffective and inefficient. Studies show that using the volume of room air as a heat exchange medium is wasteful and allows for substantial mixing of hot and cold air. Further, it limits cabinet/frame/rack density because it cannot effectively cool high heat density equipment that is spaced closely together. A more cost-effective, efficient solution for maximizing heat transfer and enabling higher heat density equipment frames can be accomplished by utilizing properly positioned “phase change” or “two-phase” pumped refrigerant cooling methods. Pumping low pressure, oil-free phase changing refrigerant through microchannel heat exchangers can provide up to 90% less energy consumption for the primary cooling loop within the room. The primary benefits of such a solution include reduced energy requirements, optimized utilization of data center space, and lower OPEX and CAPEX. Alcatel-Lucent recently developed a modular cooling technology based on a pumped two-phase refrigerant that removes heat directly at the shelf level of equipment racks. The key elements that comprise the modular cooling technology consist of the following. A pump delivers liquid refrigerant to finned microchannel heat exchangers mounted on the back of equipment racks. Fans drive air through the equipment shelf, where the air gains heat dissipated by the electronic components therein. Prior to exiting the rack, the heated air passes through the heat exchangers, where it is cooled back down to the temperature level of the air entering the frame by vaporization of the refrigerant, which is subsequently returned to a condenser where it is liquefied and recirculated by the pump. All the cooling air enters and leaves the shelves/racks at nominally the same temperature. Results of a 100 kW prototype data center ...
Date: December 13, 2012
Creator: Salamon, Todd
Partner: UNT Libraries Government Documents Department

HANFORD WELLS

Description: This report provides a complete documentation of wells in and adjacent to the Hanford Site.
Date: May 1, 1979
Creator: McGhan, VL, Damschen, DW
Partner: UNT Libraries Government Documents Department