Bioresource and Agricultural Engineering Commons^™

Comparison Of Dynamic Compression Behavior Of Single Crystal Sapphire To Polycrystalline Alumina, G. J. Kleiser, L.C. Chhabildas, W.D. Reinhart

United States Department of Energy: Publications

Due to the considerable interest in the shock loading behavior of aluminum oxide whether it is in the polycrystalline phase or in the single crystal phase well-controlled experiments were conducted to probe differences in shock loading behavior between these two materials. Previous studies concluded that the behavior was similar but careful examination of well-controlled experiments has revealed the two materials are different.Although the experimental results appear to have the same behavior in the shock velocity vs. particle velocity plane, they are considerably different in the stressevolume compression plane and evidence is provided that indicates the single crystal remains crystalline up …

Persistence Of Uranium Groundwater Plumes: Contrasting Mechanisms At Two Contaminated Doe Sites, John M. Zachara, James A. Davis, Philip E. Long, Kenneth H. Williams, Mark Freshley, James P. Mckinley

United States Department of Energy: Publications

We examine subsurface uranium (U) plumes at two U.S. Department of Energy sites located near large river systems. Following excavation of contaminated materials, both sites were projected to naturally flush remnant uranium contamination to levels below regulatory limits (e.g., 30 μg/L), within 10 years at the Hanford 300 Area (Columbia River) and 12 years at the Rifle site (Colorado River). The observed rate of attenuation was much lower than expected at both sites. Current understanding suggests that the two sites have common, but also differing mechanisms controlling plume persistence. At Hanford, the persistent source is adsorbed U(VI) in the deep …

Monarch: A High-Assurance Java-To-Java (J2j) Source-Code Migrator, Victor L. Winter, Jonathan Guerrero, Carl Reinke, James T. Perry

United States Department of Energy: Publications

JVM-based processors used in embedded systems are often scaled back versions of the standard JVM which do not support the full set of Java byte codes and native methods assumed by a JVM. As a result, code bases such as Java libraries must be migrated in order make them suitable for execution on the embedded JVM-based processor. This paper describes Monarch, a high-assurance Java-to-java (J2j) source code migrator that we are developing to assist such code migrations.

Effect Of Additive On The Performance Characteristics Of Centrifugal And Progressive Cavity Slurry Pumps With High Concentration Fly Ash Slurries, Sunil Chandel, S.N. Singh, V. Seshadri

Coal Combustion and Gasification Products Journal Archive

Slurry pumps that are used in the hydraulic transportation of fly ash slurries through pipes in thermal power plants can be broadly classified into two main categories namely positive displacement and centrifugal pumps. The two types of pumps differ considerably in construction as well as in operating principle compared to the conventional pumps. The present study reports the effect of additive on the performance characteristics of centrifugal and progressive cavity screw pumps with fly ash slurries at high concentrations (above Cw < 50% by weight). Mixture of sodium carbonate and Henko detergent (5:1) at a concentration of 0.2% by weight has been used as an additive. For each type of pump, the effect of additive on the performance characteristics has been experimentally evaluated at rated speed with fly ash slurries in the concentration range of 50 to 70% by weight. The pump total head, overall efficiency and pump input power as a function of flow rate have been measured. The results obtained from the centrifugal slurry pump performance show that at rated speed, the performance of the pump improves with the addition of drag reducing additive. In the case of progressive cavity screw pump, pump performance characteristics and behavior were completely different as compared to the centrifugal slurry pump. At rated speed, the performance of screw pump deteriorates with the addition of drag reducing soap solution.

Variable Frequency Drive (Vfd) Controlled Irrigation Pumps – Analysis Of Potential Rebate, Charles M. Burt

BioResource and Agricultural Engineering

Well pumps, booster pumps, and a combination of the two are used throughout the agricultural sector to provide water for on-farm irrigation. However, the pump discharge pressures for the majority of irrigation systems are excessive, waiving considerable monetary and power consumption savings. This report analyzes the numerous potential benefits of integrating a variable frequency drive (VFD) to irrigation supply systems and modifying system design philosophies.

Low Pressure Drip/Micro System Design – Analysis Of Potential Rebate, Charles M. Burt, Daniel J. Howes

BioResource and Agricultural Engineering

Drip/micro irrigation systems are often referred to as “low pressure” systems because the required emitter pressures are relatively low (6-12 psi). However, the pump discharge pressures of systems on flat ground throughout California average 40 psi. This report examines readily attainable system losses by examining individual components of the drip/micro system.

Irrigation District Flow Metering, Charles M. Burt

BioResource and Agricultural Engineering

Most readers of this publication are probably somewhat familiar with USBR Reclamation Reform Act requirements for measurement of water deliveries to farm turnouts, in cases where the water is supplied by Reclamation facilities. Basically, volumes within the Mid-Pacific Region are supposed to be measured within ±6%. This sounds like a fairly straightforward requirement, but the reality is anything but simple.

Characteristics Of Pump Performance In Major Irrigated Areas Of California, Sierra A. Orvis Layous, Charles M. Burt, Luis P. Urrestarazu

BioResource and Agricultural Engineering

Well pump tests (12,876) in three Central California groundwater basins were characterized and described according to their spatial distribution. The average overall pumping plant efficiency (wire-water, not including column losses and velocity head) was about 56%. Characteristics such as drawdown, total dynamic heads, kW, and flow rate vary greatly between pumps within and between sub-basins. This is the first well pump characterization of its type in California, although irrigation pump tests have been conducted for over 70 years in California. This paper provides a summary of the spatial variation of well pump performance and characteristics.

The Irrigation Sector Shift From Construction To Modernization: What Is Required For Success?, Charles M. Burt

BioResource and Agricultural Engineering

External pressures related to environmental protection, commodity prices, energy availability, larger populations, and climate change have combined to require an immediate and substantial improvement in agricultural irrigation performance. Worldwide progression towards modernized irrigation projects has been uneven and slower than desired, but decades of irrigation modernization development have clarified certain requirements for success, as well as illuminated indicators of project failure. Of particular importance are required shifts within the state and national irrigation bureaucracies, as well as universities.

Motor Reference, Mohamed Grissa

BioResource and Agricultural Engineering

This document contains summary information about the following motor topics:

• Motor selection information
• AC induction motors
• Inverter duty motors
• Variable frequency drives
• Motor losses
• Troubleshooting

The information contained in this document was gathered from a variety of online, interview, and print sources, including NEMA specifications, with support from the California Energy Commission (CEC) PIER Program.

Drip Irrigation System Cost Sharing By Irrigation Districts For Water Conservation, Charles M. Burt

BioResource and Agricultural Engineering

Government and irrigation district cost sharing programs have often included financial support for the installation of drip/micro irrigation systems. These programs seek advantages that might include improved crop yield, less applied water, and a reduction in subsurface drainage water and surface tailwater. They may also seek to reduce water consumption. The actual results have been shown to vary by district, hydrology, and crop.

It is true that drip systems in California, on average, have good Distribution Uniformities (DU) of irrigation water – meaning that there are only minor differences between the depths of water received by various plants throughout a …

Effects Of Damköhler Number On Flame Extinction And Reignition In Turbulent Non-Premixed Flames Using Dns, David Lignell, Jacqueline Chen, Hans Schmutz

United States Department of Energy: Publications

Results from a parametric study of flame extinction and reignition with varying Damköhler number using direct numerical simulation are presented. Three planar, non-premixed ethylene jet flames were simulated at a constant Reynolds number of 5120. The fuel and oxidizer stream compositions were varied to adjust the steady laminar extinction scalar dissipation rate, while maintaining constant flow and geometric conditions. Peak flame extinction varies from approximately 40% to nearly global blowout as the Damköhler number decreases. The degree of extinction significantly affects the development of the jets and the degree of mixing of fuel, oxidizer, and combustion products prior to reignition. …

Variational Theory And Domain Decomposition For Nonlocal Problems, Burak Aksoylu, Michael L. Parks

United States Department of Energy: Publications

In this article we present the first results on domain decomposition methods for nonlocal operators. We present a nonlocal variational formulation for these operators and establish the well-posedness of associated boundary value problems, proving a nonlocal Poincaré inequality. To determine the conditioning of the discretized operator, we prove a spectral equivalence which leads to a mesh size independent upper bound for the condition number of the stiffness matrix. We then introduce a nonlocal two-domain variational formulation utilizing nonlocal transmission conditions, and prove equivalence with the single-domain formulation. A nonlocal Schur complement is introduced. We establish condition number bounds for the …

Automated Analysis Of Mouse Serum Peptidome Using Restricted Access Media And Nanoliquid Chromatography–Tandem Mass Spectrometry, Geun-Cheol Gil, Jim Brennan, Dan Throckmorton, Steven Branda, Gabriela Chirica

United States Department of Energy: Publications

We demonstrate use of restricted access media with reversed phase functionality (RAM-RP) for analysis of low molecular weight proteins and peptides in mouse serum (75ml) using a custom designed modular automated processing system (MAPS). RAM-RP fractionation with simultaneous removal of high molecular weight and high abundance proteins is integrated with a follow-on buffer exchange module (BE) to ensure compatibility with subsequent processing steps (trypsin digestion and intact peptide separation prior to mass spectrometric analysis). The high sample capacity afforded by chromatographic methods generates enough sample to achieve comprehensive serum peptidome identification (357 proteins) through tandem mass spectrometric analysis of both …

An Experimental And Kinetic Modeling Study Of Methyl Formate Low-Pressure Flames, S. Dooley, F. L. Dryer, B. Yang, J. Wang, T. A. Cool, T. Kasper, N. Hansen

United States Department of Energy: Publications

The oxidation of methyl formate (CH₃OCHO), the simplest methyl ester, is studied in a series of burnerstabilized laminar flames at pressures of 22–30 Torr and equivalence ratios (Φ) from 1.0 to 1.8 for flame conditions of 25–35% fuel. Flame structures are determined by quantitative measurements of species mole fractions with flame-sampling molecular-beam synchrotron photoionization mass spectrometry (PIMS). Methyl formate is observed to be converted to methanol, formaldehyde and methane as major intermediate species of mechanistic relevance. Smaller amounts of ethylene and acetylene are also formed from methyl formate oxidation. Reactant, product and major intermediate species profiles …

Reducing Error And Measurement Time In Impedance Spectroscopy Using Model Based Optimal Experimental Design, Francesco Ciucci, Thomas Carraro, William Chueh, Wei Lai

United States Department of Energy: Publications

In this work we introduce several novel tools for the reduction of errors in parameters estimated with electrochemical impedance spectroscopy experiments. An optimization strategy is developed that minimizes an estimate of the errors on the parameters while bounding the experimental time. The approach is also used to reduce experimental time while keeping a bound on the parameter errors. This feature is particularly critical in systems changing significantly within the experimental time. The paper uses a fuel cell electrode model to test this methodology and presents a real time algorithm for coupling experiment with the parameter estimation and experimental optimization.

Real-Space Study Of The Growth Of Magnesium On Ruthenium, T. Herranz, B. Santos, K.F. Mccarty, J. De La Figuera

United States Department of Energy: Publications

The growth of magnesium on ruthenium has been studied by low-energy electron microscopy (LEEM) and scanning tunneling microscopy (STM). In LEEM, a layer-by-layer growth is observed except in the first monolayer, where the completion of the first layer in inferred by a clear peak in electron reflectivity. Desorption from the films is readily observable at 400 K. Real-space STM and low-energy electron diffraction confirm that sub-monolayer coverage presents a moiré pattern with a 12 Å periodicity, which evolves with further Mg deposition by compressing the Mg layer to a 22 Å periodicity. Layer-by-layer growth is followed in LEEM up to …

Methods For Probabilistic Modeling Of Concentrating Solar Power Plants, Clifford Ho, Siri S. Khalsa, Gregory J. Kolb

United States Department of Energy: Publications

Probabilistic modeling of concentrating solar power technologies provides important information regarding uncertainties and sensitivities not available from deterministic models. Benefits of using probabilistic models include quantification of uncertainties inherent in the system and characterization of their impact on system performance and economics. This paper presents the tools necessary to conduct probabilistic modeling of concentrating solar technologies. The probabilistic method begins with the identification of uncertain variables and the assignment of appropriate distributions for those variables. Those parameters are then sampled using a stratified method (Latin Hypercube Sampling) to ensure complete and representative sampling from each distribution. Models of performance, reliability, …

Magnetically Driven Hyper-Velocity Launch Capability At The Sandia Z Accelerator, R. W. Lemke, M. D. Knudson,, J. P. Davis

United States Department of Energy: Publications

The intense magnetic field generated by the Z accelerator at Sandia National Laboratories is used as a pressure source for material science studies. A current of ∼20 MA can be delivered to the loads used in experiments on a time scale of ∼100-600 ns. Magnetic fields (pressures) exceeding 1200 T (600 GPa) have been produced in planar configurations. In one application we have developed, the magnetic pressure launches a flyer plate to ultra-high velocity in a plate impact experiment; equation of state data is obtained on the Hugoniot of a material that is shock compressed to multi-megabar pressure. This capability …

Multiple Benzene-Formation Paths In A Fuel-Rich Cyclohexane Flame, Wenjun Li, Matthew Law, Phillip Westmoreland, Tina Kasper, Nils Hansen, Katharina Kohse-Höinghaus

United States Department of Energy: Publications

Detailed data and modeling of cyclohexane flames establish that a mixture of pathways contributes to benzene formation and that this mixture changes with stoichiometry. Mole-fraction profiles are mapped for more than 40 species in a fuel-rich, premixed flat flame (Φ = 2.0, cyclohexane/O₂/30% Ar, 30 Torr, 50.0 cm/s) using molecular-beam mass spectrometry with VUV-photoionization at the Advanced Light Source of the Lawrence Berkeley National Laboratory. The use of a newly constructed set of reactions leads to an excellent simulation of this flame and an earlier stoichiometric flame (M.E. Law et al., Proc. Combust. Inst. 31 (2007) 565–573), …