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There are significant variations in the fuel consumption of aircraft during the descent phase of a flight. This paper uses aircraft flight data measurements to develop an improved understanding of these variations. A model of the aircraft engines is developed that is matched to flight data and shown to reproduce the time history of engine parameters. This model is used to determine the overall engine efficiency at each point during a descent. This enables an energy breakdown to be completed, in terms of mechanical energy from fuel, gravitational potential energy and kinetic energy. During descent, the aircraft engines operate at low overall pressure ratios corresponding to low fuel flow rates and low overall efficiencies. On average, the engine overall efficiency during descent is one-third of cruise efficiency. The airframe aerodynamic performance is deteriorated during descent with an average lift-to-drag ratio that is 87% of the average value at cruise. There are also large variations in air-track efficiency, and for the flights analysed the great circle descent distance was found to be 85% of the average descent air distance. To minimise fuel burn, flights should cruise as far as possible before starting descent and follow a trajectory with the shortest possible air distance. The descent air speed should be set to maximise the aircraft lift-to-drag ratio. Such descents could save up to 0.5% of the total aircraft mass in fuel.

Genesis is a compact pulsed power platform designed by Sandia National Laboratories to generate precision shaped multi-MA current waves with a rise time of 200-500 ns. In this system, two hundred and forty, 200 kV, 80 kA modules are selectively triggered to produce 280 kbar of magnetic pressure (>;500 kbar pressure in high Z materials) in a stripline load for dynamic materials properties research. This new capability incorporates the use of solid dielectrics to reduce system inductance and size, programmable current shaping, and gas switches that must perform over a large range of operating conditions. Research has continued on this technology base with a focus on demonstrating the integrated performance of key concepts into a Genesis-like prototype called Protogen. Protogen measures approximately 1.4 m by 1.4 m and is designed to hold 12 Genesis modules. A fixed inductance load will allow rep-rate operation for component reliability and system lifetime experiments at the extreme electric field operating conditions expected in Genesis.

The success of dynamic materials properties research at Sandia National Laboratories has led to research into ultralow impedance, compact pulsed power systems capable of multi-MA shaped current pulses with rise times ranging from 220 to 500 ns. The Genesis design consists of two hundred and forty 200 kV, 80 kA modules connected in parallel to a solid dielectric disk transmission line and is capable of producing 280 kbar of magnetic pressure (>; 500 kbar pressure in high Z materials) in a 1.75 nH, 20-mm wide stripline load. Stripline loads operating under these conditions expand during the experiment resulting in a time-varying load that can impact the performance and lifetime of the system. This paper provides analysis of time-varying stripline loads and the impact of these loads on system performance. Further, an approach to reduce dielectric stress levels through active damping is presented as a means to increase system reliability and lifetime.

Enabling technologies are being developed at Sandia National Laboratories to improve the performance and flexibility of compact pulsed-power drivers for magnetically driven dynamic materials properties research. We have designed a modular system that is capable of precision current pulse shaping through the selective triggering of pulse-forming components into a disk transmission line feeding a strip line load. The system is composed of 240 200-kV 60-kA modules in a low-inductance configuration that is capable of producing 250-350 kbar of magnetic pressure in a 1.75-nH 20-mm-wide strip line load. The system, called Genesis , measures approximately 5 m in diameter and is capable of producing shaped currents that are greater than 5 MA. This performance is enabled through the use of a serviceable solid-dielectric insulator system which minimizes the system inductance and reduces the stored energy and operating voltage requirements. Genesis can be programmed by the user to generate precision pulse shapes with rise times of 220-500 ns, allowing characterization of a range of materials from tungsten to polypropylene. This paper provides an overview of the Genesis design, including the use of genetic optimization to shape currents through selective module triggering.

To demonstrate the clinical and reproductive safety in ewes and their offspring of repetitive oral doses of monepantel, an amino-acetonitrile derivative (AAD), when administered at three times the proposed maximum recommended dose (MRD) over an entire reproductive cycle.A randomised controlled blinded study design was used. One hundred and twelve primi- or multi-parous ewes and 28 rams were randomly allocated into control and treated groups (n=56 for groups of ewes, n=14 for groups of rams). Two control ewes and two treated ewes were randomly selected to form 28 subgroups. A control or treated ram was then randomly allocated to each subgroup, to form control ram/treated ewe, control ram/control ewe, treated ram/treated ewe, and treated ram/control ewe 'treatment/mating' units. Control animals were treated with saline, and treated animals given three times the MRD (11.25 mg/kg) of monepantel. Treatments were administered orally every 5 days during an entire reproductive cycle, including oestrus and mating, gestation, and post-lambing to weaning. Detailed recording at multiple time points were made of veterinary examinations; observations for adverse events; bodyweight measurements; faecal scores; and haematology, clinical chemistry and coagulation variables. Reproductive indices determined included percent pregnant, number of failed embryos, abortion percentage, number of lambs with teratogenic defects, length of gestation, percentage of stillbirths, number of ewes experiencing reproductive problems, lambing percentage, and pre-weaning mortality. Post-mortem examination, including measurement of organ weights, was performed on randomly selected ewes (n=40) and lambs (n=40) at the completion of the study.All ewes treated with monepantel and those in the control group thrived and behaved normally to the end of the study. No treatment-related, toxicologically relevant adverse events, clinical observations or gross post-mortem changes were observed. Furthermore, there were no significant differences in bodyweight or organ weights, and haematological, clinical chemistry or coagulation variables between ewes treated with monepantel and control ewes. No significant differences were observed in any of the reproductive indices measured. No significant clinical differences were noted between lambs born from treated ewes and those from controls.Repeated oral administration of monepantel at three times the MRD every 5 days over an entire reproductive cycle was not associated with any treatment-related adverse effects on the reproductive performance of ewes nor on the viability of their offspring, and was systemically very well tolerated. This study demonstrated that this population of ewes could tolerate accidental overdoses of up to three times the MRD of monepantel or prolonged repetitive administration of overdoses. Thus, those so treated entering a breeding programme would have normal reproductive indices, mating behaviour, and health, and their lambs would suffer no ill effects.

When uranium alloyed with 6-wt% niobium (U–6Nb) is rapidly compressed in uniaxial strain experiments, shear stress is observed to relax with a characteristic time of 30 ± 7 ns. In shock wave experiments, this relaxation inhibits the development of an elastic precursor commonly seen in other materials. When U–6Nb is cold-rolled to pre-twin and significantly increase the density of dislocations in the material, stress relaxation effects are diminished suggesting that twinning causes relaxation in the un-worked material. Separate ramp wave compression experiments produce effects that agree with those observed in shock-loading experiments. A phenomenological model is introduced that allows accurate simulation of all experiments. Estimates of residual shear stress after relaxation are obtained.

The transformation of liquid water to solid ice is typically a slow process. To cool a sample below the melting point requires some time, as does nucleation from the metastable liquid1, so freezing usually occurs over many seconds2. Freezing conditions can be created much more quickly using isentropic compression techniques, which provide insight into the limiting timescales of the phase transition. Here, we show that water rapidly freezes without a nucleator under sufficient compression, establishing a practical limit for the metastable liquid phase. Above 7 GPa, compressed water completely transforms to a high-pressure phase within a few nanoseconds. The consistent observation of freezing with different samples and container materials suggests that the transition nucleates homogeneously. The observation of complete freezing on these timescales further implies that the liquid reaches a hypercooled state3.

Colour is an important feature that increases the visibility of objects and may aid recognition of con-specifics. The adaptive significance of the ability to utilize colour cues has been demonstrated in a number of species, in particular in relation to food selection. The evolution of trichromatic colour vision in primates has been associated with the advantages that it provided in the selection of yellow and orange fruits (Mollon, 1989) or tender young red foliage (Dominy and Lucas, 2001) from a background of green. The horse is a generalist herbivore that must both select nutritious plants and avoid toxic ones. Familiarity is an important factor in this selection process (Augneret al., 1998), although it is not clear exactly what features are used to recognise previously ingested and “safe” herbage.The horse has been shown to possess dichromatic colour vision. There are two types of cone photopigment in the equine retina, with spectral peaks at 429 and 545 nanometres (Macuda, 2000).

The Z accelerator at Sandia National Laboratories was used to measure the compression isentrope of 6061-T6 aluminum to 185GPa. The isentropic compression experimental technique uses a rapidly increasing, planar magnetic field to simultaneously subject multiple planar aluminum samples of different thicknesses to a ramped magnetic stress load. This magnetic stress load causes a ramped compression wave to propagate in the aluminum. Motion histories at the rear surface of each aluminum sample are measured through a LiF window using laser velocity interferometry. Backward and forward integration of the one-dimensional equations of motion are used to analyze the data. Imposing the requirement that each motion history comes from the same magnetic stress load is sufficient to determine both the stress load and the stress-strain behavior of the aluminum. Because of shocks that grow in the LiF, the usual VISAR interferometer analysis was modified. The measured compression curve obtained on different aluminum samples for volumetric strains to 46% agrees to within about 2% of peak stress with an isentrope obtained from the often-used Mie-Gruneisen equation of state that was derived from previous Hugoniot data.

Hugoniot measurements were performed on aluminum (6061-T6) in the stress range of 100–500 GPa (1–5 Mbar) using a magnetically accelerated flyer plate technique. This method of flyer plate launch utilizes the high currents, and resulting magnetic fields produced at the Sandia Z Accelerator to accelerate macroscopic aluminum flyer plates (approximately 12×25 mm in lateral dimension and ∼300 μm in thickness) to velocities in excess of 20 km/s. This technique was used to perform plate-impact shock-wave experiments on aluminum to determine the high-stress equation of state (EOS). Using a near-symmetric impact method, Hugoniot measurements were obtained in the stress range of 100–500 GPa. The results of these experiments are in excellent agreement with previously reported Hugoniot measurements of aluminum in this stress range. The agreement at lower stress, where highly accurate gas gun data exist, establishes the magnetically accelerated flyer plate technique as a suitable method for generating EOS data. Furthermore, the present results exhibit increased accuracy over the previous techniques used to obtain data in the higher-stress range. This improved accuracy enhances our understanding of the response of aluminum to 500 GPa, and lends increased confidence to the use of aluminum as a standard material in future impedance matching experiments.

Isentropic compression experiments (ICE) on Sandia National Laboratories’ Z Accelerator are used to make continuous measurements of the index of refraction in single crystal Z-cut sapphire as the longitudinal stress is gradually increased to 20 GPa (uniaxial strain of about ∼3.9%). A planar, ramp compression wave, generated by a large magnetic field, propagates through a planar copper base plate. Part of the rear surface of the base plate is a free surface and part is covered with a sapphire window. Comparisons are made of velocity histories measured simultaneously at the free surface and at the copper/sapphire interface using a velocity interferometer system for any reflector (VISAR). This is sufficient to determine the index of refraction of the sapphire continuously as a function of density. Perturbations to the compression waves caused by interactions with the free surface and with the sapphire are accounted for by backward or forward solutions to the equations of motion. The effect of the unsteady na...

The present work describes the compression and release response of a glass-fiber-reinforced polyester composite (GRP) under shock loading to 20 GPa. Shock experiments in GRP were performed at Sandia National Laboratories and the US Army Research Laboratory. GRP is a heterogeneous material. The diagnostic measurements fluctuate beyond the precision of the experimental measurements but they do permit determination of an average response of the material at the end state. These experiments show that: (i) GRP deforms elastically in compression to at least 1.3 GPa; (ii) the deformation coordinates of shocked and re-shocked GRP lie on the deformation locus of initially shocked GRP to 4.3 GPa; (iii) and the release path of GRP shocked to varying magnitudes of stresses indicate that the GRP expands such that its density when stresses are released in the range of 3–5 GPa from a peak compressive stress of 9 GPa and above is lower than the initial density of GRP. Possible reasons for the observed lower density remain to be investigated.

The intense magnetic field generated by the 20 megaampere Z machine [R. B. Spielman et al., Phys. Plasmas 5, 2105 (1998)] at Sandia National Laboratories is being used as a pressure source for material science studies. An application we have studied in great detail involves using the intense magnetic field to accelerate flyer plates (small metal disks) to very high velocities (>20 km/s) for use in shock loading experiments. We have used highly accurate velocity interferometry measurements (error ∼1%) in conjunction with one-dimensional magnetohydrodynamic (MHD) simulation to elucidate details of the flyer dynamics. One-dimensional MHD simulations are able to produce experimental results with a high degree of accuracy, thereby revealing otherwise unobtainable, but useful information about magnetically accelerated flyers on Z. Comparisons of simulation results with time-resolved measurements of velocity from a shock loading experiment involving a 925 μm aluminum flyer are presented. Results show that Joule ...

Isentropic compression experiments that utilize intense magnetic fields to compress samples have been designed, developed and performed. The technique has been shown to work to pressures of more than 1 Mbar on Sandia National Laboratory's Z pulsed power machine. We are extending the technique to use high-explosive pulsed power.

Introduction: We examined persons transported to hospital after police use of force to determine whether Emergency Department (ED) assessment and/or mode of transport could be predicted. Methods: A multi-site prospective consecutive cohort study of police use of force with data on ED assessment for individuals ≥18 yrs was conducted over 36 months (Jan 2010-Dec 2012) in 4 cities in Canada. Police, EMS and hospital data were linked by study ID. Stepwise logistic regression examined the relationship between the police call for service and subject characteristics on subsequent ED assessment and mode of transport. Results: In 3310 use of force events, 86.7% of subjects were male, median age 29 yrs. ED transport occurred in 26% (n=726). Odds of ED assessment increased by 1.2 (CI 1.1, 1.3) for each force modality >1. Other predictors of ED use: if the nature of police call was for Mental Health Act (MHA) (Odds 14.3, CI 10.6, 19.2), features of excited delirium (ExD) (Odds 2.7, CI 1.9, 3.7), police-assessed emotional distress (EDP) not an MHA (Odds 2.1, CI 1.5, 3.0) and combined drugs, alcohol and EDP (Odds 1.7, CI 1.9, 3.7). Those with alcohol impairment alone were less likely to go to ED from the scene: OR 0.6 (CI 0.5, 0.7). EMS transported 55% of all patients (n=401), although police transported ~100 people who EMS attended at the scene but did not subsequently transport. For patients brought to the ED, 70% had a retrievable chart (512/726) with a discernible primary diagnosis: 25% for physical injury, 32% for psychiatric and 43% for drug and/or alcohol intoxication. For use of force events that began as MHA calls, patient transport was more often by police car than ambulance OR 1.8 (CI 1.2, 2.5), while those with drug intoxication or ≥3 ExD features were more often brought by ambulance: odds of police transport 0.5 (CI 0.3, 0.9) and 0.4 (CI 0.3, 0.7). Violence or aggression did not predict mode of transport in our study. Conclusion: About one quarter of police use of force events lead to ED assessment; 1 in 4 patients transported had a physical injury of some description. Calls including the Mental Health Act or individuals with drug intoxication or excited delirium features are most predictive of ED use following police use of force. In MHA calls with use of force, persons are nearly twice as likely to go to ED by police car than by ambulance.

This chapter introduces the book on fluid mechanics and the thermodynamics of turbomachines. The book examines, through the laws of fluid mechanics and thermodynamics, the means by which the energy transfer is achieved in the chief types of turbomachines, together with the differing behavior of individual types in their operations. The turbomachines are devices in which energy is transferred continuously flowing fluid by the dynamic action of one or more moving blade rows. Two main categories of turbomachines are identified—those that absorb power to increase the fluid pressure or head (ducted and unducted fans, compressors, and pumps) and those that produce power by expanding fluid to a lower pressure or head (wind, hydraulic, steam, and gas turbines). Methods of analyzing the flow processes differ depending upon the geometrical configuration of the machine. The most fundamental and valuable principles in fluid mechanics is Newton's second law of motion. The momentum equation relates the sum of the external forces acting on a fluid element to its acceleration, or to the rate of change of momentum in the direction of the resultant external force. The chapter presents the basic physical laws of fluid mechanics and thermodynamics, developing them into a form suitable for the study of turbomachines such as the continuity of flow equation, the first law of thermodynamics and the steady flow energy equation, the momentum equation, and the second law of thermodynamics. The energy and entropy equations are introduced in the chapter, along with all-important Euler work equation, which applies to all turbomachines. It also presents important efficiencies such as efficiency of turbines, steam and gas turbines, hydraulic turbines, and compressors and pumps.

The chapter discusses the concept of a radial flow turbine that is used for producing hydraulic power. It discusses mainly two types of radial flow turbines—the inward flow radial flow (IFR) and outward flow gas turbines. The IFR turbine covers tremendous ranges of power, rates of mass flow, and rotational speeds, from very large outwards turbines used in hydroelectric power for the generation of hundreds of megawatts down to tiny closed cycle gas turbines for the space power generation of a few kilowatts. The IFR gas turbine continues to be used extensively for powering automotive turbo charges, aircraft auxiliary power units, and expansion units in gas liquefaction. Over a limited range of specific speed, IFR turbines provide efficiency about equal to that of the best axial-flow turbines. The significant advantages offered by the IFR turbine compared with the axial-flow turbine are the greater amount of work that can be obtained per stage, the ease of manufacture, and its superior ruggedness. Different types of inward turbines are also discussed in this chapter, along with the optimum design selection of IFR turbines including factors such as nozzle blade row boundary layers, rotor passage boundary layers, disc wind age, and kinetic energy loss at exit.

Publisher Summary The design and performance prediction of axial flow compressors and turbines has been based upon the measurements of the flow-through two-dimensional cascades of blades. For cascade analysis, the flow across individual blade rows is treated as two-dimensional and steady. This approach is appropriate for many compressor and turbine designs and the derived flow characteristics obtained from cascade tests have usually been found to be satisfactory, although laborious to collect. It is most important that the flow across the central region of the cascade blades is a good approximation to two-dimensional flow and that the flow repeats across several blade pitches. This effect could be achieved by employing a large number of long blades, but then an excessive amount of power would be required to operate the tunnel. A cascade blade profile can be conceived as a curved camber line upon which a profile thickness distribution is symmetrically superimposed. Cascade flow characteristics such as streamtube thickness variation, cascade performance parameters, and blade surface velocity distributions are discussed in the chapter. This also includes discussion on the compressor cascade performance, turbine cascade performance, and the analysis of cascade.

Publisher Summary This chapter focuses on the three-dimensional flow in axial turbomachinery. An analysis called the “radial equilibrium method,” widely used for three-dimensional design calculations in axial compressors and turbines, is based upon the assumption that any radial flow occurring is completed within a blade row. The radial equilibrium equation applies to compressible flow as well as incompressible flow. With constant stagnation enthalpy and constant entropy, a free-vortex flow, therefore, implies uniform axial velocity downstream of a blade row, regardless of any density changes incurred in passing through the blade row. The design problem (the tangential velocity distribution) with the axial velocity variation and the direct problem (the swirl angle distribution), with the axial and tangential velocities being determined, are specified in the chapter. It also includes an introduction to the subject of computational fluid dynamics that plays a large part in turbomachinery design and analysis. All the principles detailed in this chapter are equally applicable to the numerical and experimental studies of turbomachines. Radial turbomachinery remains hugely important for a vast number of applications such as turbo charging for internal combustion engines, oil and gas transportation, and air liquefaction. As jet engine cores become more compact, there is also the possibility of radial machines finding new uses within aerospace applications.

This chapter covers the following topics: Features of hydraulic turbines; Early history and development; Efficiency of various types of turbine; Size of the various turbine types; The Pelton wheel turbine and controlling its speed; Energy losses; Reaction turbines; The Francis and the Kaplan turbines; Calculation of performance; Effect of size on the performance of hydraulic turbines; Cavitation and its avoidance; Calculation of the various specific speeds of turbines; The Wells turbine- Design and performance variables; Tidal power turbines- The SeaGen tidal turbine and its operational principles.

Publisher Summary The chapter elaborates the design of the modern wind turbine based upon aerodynamic principles. Wind power comes from the conversion of wind energy into electricity using wind turbines to drive the electrical generators. Wind turbines fall into two main categories—those that depend upon aerodynamic drag to drive them and those that depend upon aerodynamic lift. Different type of wind turbines such as large Horizontal-axis wind turbines (HAWTs) and small HAWTs with their height and storage capacity is also discussed in this chapter. The aerodynamic theory of the HAWT is gradually developed, starting with the simple one-dimensional momentum analysis of the actuator disc and followed by the more detailed analysis of the blade element theory. The flow state just upstream of the rotor plane forms the so-called inflow condition for the rotor blades and from this the aerodynamic forces acting on the blades can be determined. The well-known blade element momentum (BEM) method is outlined and used extensively in the chapter. A number of worked examples are included at each stage of the development to illustrate the application of the theory .The chapter outlines the availability of the wind energy and historical view point about the use of the wind turbines. It presents the very important aspects concerning the criteria of blade selection and blade manufacture, control methods for regulating power output and rotor speed, and performance testing. It also includes some notes concerning public and environmental issues, which are becoming increasingly important as they can affect the development of wind turbines.

Publisher Summary This chapter discusses the elementary flow analysis and preliminary design of radial-flow work-absorbing turbomachines comprising pumps, low speed fans, and compressors. It focuses on the compressor because the basic action of all these machines is the same. Turbomachines employing centrifugal effects for increasing fluid pressure have been in use and the earliest machines using this method were hydraulic pumps followed later by ventilating fans and blowers. The axial flow compressors are found to be better in meeting the needs of larger engines. Not only are the frontal area (and drag) smaller with engines using axial compressors but also the efficiency for the same duty is better by as much as 3 or 4%.Many applications are found in small gas turbines for road vehicles and commercial helicopters as well as bigger applications, e.g., diesel engine turbochargers, chemical plant processes, factory workshop air supplies, large-scale air-conditioning plant, etc. The chapter discusses the details for calculating the performance of centrifugal compressors with backward swept impeller vanes and presents the thermodynamic analysis of the centrifugal compressor with the help of the impeller and diffuser. The diffuser is an important element of a compressor or pump. Its purpose is to reduce the velocity of the flow leaving the impeller resulting in an increase in pressure. The optimum design of the pump and compressor is presented in this chapter. It also evaluates the performance of the pump, fan, and compressor with the help of suitable examples.

Two experiments have been performed to measure the effects of pulsed radiation loads on the front of small tubular structures, using as an energy source the X-ray fluence produced by a Z-pinch at the Sandia National Laboratories Z Facility. The project had two major goals: to establish the feasibility of using the Z machine to study the phenomenology associated with debris generation and propagation down tubular structures with partitions; and to use the resultant experimental data to validate numerical hydrocodes (shock physics codes) so that we have confidence in their use in analyzing these types of situations. Two tubular aluminum structures (5 and 10 cm long and 1 cm inside diameter) were prepared, with aluminum partitions located at the front, halfway down the pipe, and at the rear. Interferometry (VISARs) provided multiple velocity histories for all of the partitions. In both experiments, the first barrier, which was exposed directly to the x-ray fluence, was launched into the pipe at a velocity of ∼2 km/s, accelerating to give a mean velocity of ∼2.6 km/s. Loss of plate integrity is inferred from the dispersed launch of the second partition at ∼1 km/s. Wall shocks propagating at 4.5 km/s were inferred. Post-test metallography showed evidence of melting and partial vaporization of the plates, and turbulent mixing with material from the walls. Calculations qualitatively agree with the observed results, but slightly overpredict debris velocity, possibly due to overestimates of total energy fluence. An application for this work is the study of techniques for line-of-sight shock and debris mitigation on high-power pulsed power facilities such as Z and its follow-on machines.

In conjunction with ongoing high-current experiments on Sandia National Laboratories' Z accelerator we have revisited a problem first described in detail by Heinz Knoepfel (1970). Unlike the 1-Tesla MITLs of pulsed power accelerators used to produce intense particle beams, Z's disc transmission line (downstream of the current addition) is in a 100-1200 Tesla regime, so its conductors cannot be modeled simply as static infinite conductivity boundaries. Using the MHD code MACH2 we have been investigating the conductor hydrodynamics, characterizing the joule heating, magnetic field diffusion, and material deformation, pressure, and velocity over a range of current densities, current rise-times, and conductor materials. Three purposes of this work are (1) to quantify power flow losses owing to ultra-high magnetic fields, (2) to model the response of VISAR diagnostic samples in various configurations on Z, and (3) to incorporate the most appropriate equation of state and conductivity models into our MHD computations. Certain features are strongly dependent on the details of the conductivity model. Comparison with measurements on Z is discussed.

The Z Refurbishment Project was completed in September 2007. Prior to the shutdown of the Z facility in July 2006 to install the new hardware, it provided currents of {le} 20 MA to produce energetic, intense X-ray sources ({approx} 1.6 MJ, > 200 TW) for performing high energy density science experiments and to produce high magnetic fields and pressures for performing dynamic material property experiments. The refurbishment project doubled the stored energy within the existing tank structure and replaced older components with modern, conventional technology and systems that were designed to drive both short-pulse Z-pinch implosions and long-pulse dynamic material property experiments. The project goals were to increase the delivered current for additional performance capability, improve overall precision and pulse shape flexibility for better reproducibility and data quality, and provide the capacity to perform more shots. Experiments over the past year have been devoted to bringing the facility up to full operating capabilities and implementing a refurbished suite of diagnostics. In addition, we have enhanced our X-ray backlighting diagnostics through the addition of a two-frame capability to the Z-Beamlet system and the addition of a high power laser (Z-Petawatt). In this paper, we will summarize the changes made to themore » Z facility, highlight the new capabilities, and discuss the results of some of the early experiments.« less

In this paper, we describe a new technique for using a pulsed power source (Z pinch) to produce planar shock waves for high-pressure equation of state (EOS) studies. Initial EOS experiments indicate that these sources are effective for shock wave studies in samples with diameters of a few millimeters and thicknesses of a fraction of one millimeter, and thus provide the possibility for achieving accuracy in shock and particle velocity measurements of a few percent. We have used the Z pinch source to produce the first in-situ time-resolve particle velocity profiles obtained with pulsed radiation sources in the Mbar regime. Particle velocity profiles obtained with a VISAR interferometer are compared with 1-D numerical simulations performed with a radiation-hydrodynamics code, ALEGRA. Good agreement with experimental results was achieved in the simulations and suggests that the Z pinch source should be a valuable tool for high-pressure EOS studies in thermodynamic regimes important to hypervelocity impact.

A series of controlled impact experiments has been performed to determine the shock loading and release behavior of two types of concrete, differentiated by aggregate size, but with average densities varying by less than 2 percent. Hugoniot stress and subsequent release data was collected over a range of approximately 3 to 25 GPa using a plate reverberation technique in combination with velocity interferometry. The results of the current data are compared to those obtained in previous studies on concrete with a different aggregate size but similar density. Results indicate that the average loading and release behavior are comparable for the three types of concrete discussed in this paper. Residual strain is also indicated from these measurements.

The corrosion of steel and copper in contact with ester based fluid formulations in the presence of water at 150 and 60 °C has been investigated using impedance measurements, infra-red spectroscopy and weight change measurements. At 60 °C films are formed where the outer layers are loosely adherent and easily removed from the metal surface. At 150 °C, where the water content of the oil is much lower than at 60 °C, the films are much more adherent. The films consist largely of metal hydroxides at both temperatures. In the absence of oxygen very little film formation occurs.

Introduction: This study provides an estimate of the number of EMS calls related to police use of force events that involve struggling, intoxicated and/or emotionally distressed patients. We hypothesized there would be under-reporting of EMS risk by paramedic agencies due to lack of standardized reporting of police events by EMS services and lack of a common linked case number between prehospital agencies in Canada. Methods: Data were collected during a multi-site, prospective, consecutive cohort study of police use of force in 4 Canadian cities using standardized data forms. Use of force was defined a priori and the application of handcuffs was not considered a force modality. Inclusion criteria: all subjects ≥ 18 years of age involved in a use of force police-public encounter. We defined risk to EMS as the presence of police- and/or paramedic- assessments of violent or struggling subjects on the scene. Three separate data forms (police-report of use of force, EMS encounter, and Emergency Department (ED) visit) were linked in the study by unique ID. When police-reported EMS was activated, investigators hand searched the EMS service reports at the relevant agencies for matching call sheets. Results: From Jan 2010 to Dec 2012, we studied 3310 consecutive public-police interactions involving use of force above simple joint lock application. Subjects were male (86%) with a mean age of 33 yrs; 85% were assessed by police as emotionally disturbed, intoxicated with drugs and/or alcohol or a combination of those. 45% were violent at the scene. Police-reported EMS attendance in 24% (809/3310) of use of force events, of which only 43% (349/809) of EMS run sheets were available. In events with violent subjects, EMS transported 51% to ED compared to 35% by police transport (chi=79.7, p=0.00). Conclusion: We identified periods of professional and physical risk to paramedics attending police use of force events and found that risk significantly underrepresented in EMS data. Paramedical training would benefit from policy and procedures for response to police calls and the violent patient, the majority of whom are struggling. A common linked case number in prehospital care would enable more specific quantification of the risk for EMS providers involved in police events.

A systematic study is described which has led to the successful launch of thin flier plates to velocities of 16 km/s. The energy required to launch a flier plate to 16 km/s is approximately 10 to 15 times the energy required to melt and vaporize the plate. The energy must, therefore, be deposited in a well-controlled manner to prevent melt or vaporization. This is achieved by using a graded-density assembly to impact a stationary flier-plate. Upon impact, time-dependent, structured, high pressure pulses are generated and used to propel the plates to hypervelocities without melt or fracture. In previous studies, a graded-density impact of 7.3 km/s was used to launch a 0.5 mm thick plate to a velocity of over 12 km/s. If impact techniques alone were to be used to achieve flier-plate velocities approaching 16 km/s, this would require that the graded-density impact occur at - 10 km/s. In this paper, we describe a new technique that has been implemented to enhance the performance of the Sandia hypervelocity launcher. This technique of creating an impact-generated acceleration reservoir, has allowed the launch of 0.5 mm to 1.0 mm thick plates to record velocities up to 15.8 km/s. In these experiments, both titanium (Ti-6A1-4V) and aluminum (6061-T6) alloy were used for the flier-plate material. These are the highest metallic projectile plate velocities ever achieved for masses in the range of 0.1 g to 1 g.

Mathematical models for stamping of metal blanks are based upon the physical principles of equilibrium of forces, material constitutive laws and constraints resulting from contact between the blank and the press itself. We investigate singularities in the differential algebraic equation (DAE) resulting from one such model. In particular, the inability of numerical integrators to preserve anticipated symmetries in its solution as time advances is shown to be due to singularities on or close to the solution curve.

The formation of tarnish layers on copper and steel when contacted by ester fluid formulations (based on an ester fluid) at temperatures up to 200°C has been studied by a variety of techniques-principally impedance spectroscopy and infrared spectroscopy. It has been found that negligible corrosion of the metals occurs if atmospheric oxygen is excluded from the system. In the presence of atmospheric oxygen in most cases the tarnish layers consist of oxides modified by the incorporation of car☐ylate species. The layer thicknesses in some cases are less than those which would be formed if the metals were heated directly in air at the same temperature.

Recently, a numerical method was proposed for the solution of the equations of an incompressible fluid on a two dimensional grid consisting of Delaunay triangles. The method utilized the complementary grid of Voronoi polygons, as well as the dual variable reduction scheme developed by the authors. In this paper we generalize these ideas to thermally expandable, homogeneous, two-phase flow. This includes a derivation of the semi-discrete system, and the dual variable methodology that is used to solve it.

Genesis is a compact pulsed power platform designed by Sandia National Laboratories to generate precision shaped multi-MA current waves with a rise time of 200–500 ns. In this system, two hundred and forty, 200 kV, 80 kA modules are selectively triggered to produce 280 kbar of magnetic pressure (>500 kbar pressure in high Z materials) in a stripline load for dynamic materials properties research. This new capability incorporates the use of solid dielectrics to reduce system inductance and size, programmable current shaping, and gas switches that must perform over a large range of operating conditions. Research has continued on this technology base with a focus on demonstrating the integrated performance of key concepts into a Genesis-like prototype called Protogen. Protogen measures approximately 1.4 m by 1.4 m and is designed to hold twelve Genesis modules. A fixed inductance load will allow rep-rate operation for component reliability and system lifetime experiments at the extreme electric field operating conditions expected in Genesis.

The authors present the design and fabrication techniques that have been used to increase the strength of the projectiles used in the STARFIRE Project. In addition, various diagnostics that have been used to guide the projectile development and monitor projectile integrity are reviewed. Stronger projectile designs have been fabricated with a concurrent reduction in precision machining time. The improvements in projectile strength have allowed increases in reliable projectile injection velocities from 6 km/s to 7 km/s. In addition, the molded projectile fabrication technique offers additional flexibility for the fabrication of complex projectile designs. One of these advanced projectile concepts which uses a base sealing design offers the potential for further increases in injection velocity. >

Experiments have been performed on NASA state-of-the-art hypervelocity impact shields using the Sandia Hypervelocity Launcher (HVL) to obtain test velocities greater than those achievable using conventional two stage light-gas sun technology. The objective of the tests was to provide the first experimental data on the advanced shielding concepts for evaluation of the analytical equations (shield performance predictors) at velocities previously unattainable in the laboratory, and for comparison to single Whipple Bumper Shileds (WBS) under similar loading conditions. The results indicate that significantly more mass is required on the back sheet of the WBS to stop an approximately flat-plate particle impacting at 7 km/sec and at 10 km/sec that the analytical equations (derived from spherical particle impact data) predicted. The Multi-Shock Shield (MSS) consists of four ceramic fabric bumpers, and is lighter in terms of areal density by up to 33%, but is as effective as the heavier WBS under similar impact conditions at about 10 km/s. The Mesh Double Bumper shield (MDB) consists of an aluminum wire mesh bumper, followed by a sheet of solid aluminum and a layer of Kevlar ® fabric. It provides a weight savings in terms of areal density of up to 35% compared to the WBS for impacts of around 10 km/s.

Publisher Summary The chapter discusses the concept of a radial flow turbine that is used for producing hydraulic power. It discusses mainly two types of radial flow turbines—the inward flow radial flow (IFR) and outward flow gas turbines. The IFR turbine covers tremendous ranges of power, rates of mass flow, and rotational speeds, from very large outwards turbines used in hydroelectric power for the generation of hundreds of megawatts down to tiny closed cycle gas turbines for the space power generation of a few kilowatts. The IFR gas turbine continues to be used extensively for powering automotive turbo charges, aircraft auxiliary power units, and expansion units in gas liquefaction. Over a limited range of specific speed, IFR turbines provide efficiency about equal to that of the best axial-flow turbines. The significant advantages offered by the IFR turbine compared with the axial-flow turbine are the greater amount of work that can be obtained per stage, the ease of manufacture, and its superior ruggedness. Different types of inward turbines are also discussed in this chapter, along with the optimum design selection of IFR turbines including factors such as nozzle blade row boundary layers, rotor passage boundary layers, disc wind age, and kinetic energy loss at exit.

Publisher Summary This chapter presents the basic characteristics of axial-flow compressors and ducted fans. It also covers the analysis of axial-flow compressors stage (mean-line analysis, velocity diagrams, thermodynamics, and stage loss relationships and efficiency) and axial-flow compressors rotors. Many axial compressors are multi-stage devices and repeating stages are initially assumed in which the velocity triangles for all stages are similar, the mean radius is constant, and the axial velocity through the machine is constant. The chapter covers the main preliminary design considerations such as stage loading, flow coefficient, reaction, inter-stage swirl, and blade aspect ratio. This includes a new presentation of the ways through which the measurements of cascade loss and turning can be translated into the performance of a compressor stage. Both incompressible and compressible cases are covered in the chapter and the huge importance of off-design performance is presented in detail including the ways a designer can influence compressor operating range during the very early design stages. For preliminary design and analysis purposes, a multi-stage compressor is thought of as a series of single-stage compressors, each performing as it would in isolation. However, to understand the performance of a real machine, the behavior of the overall system must be considered in more detail. This is particularly important to understand the sources of loss in a compressor and the off-design operation.

Publisher Summary This chapter introduces the book on fluid mechanics and the thermodynamics of turbomachines. The book examines, through the laws of fluid mechanics and thermodynamics, the means by which the energy transfer is achieved in the chief types of turbomachines, together with the differing behavior of individual types in their operations. The turbomachines are devices in which energy is transferred continuously flowing fluid by the dynamic action of one or more moving blade rows. Two main categories of turbomachines are identified—those that absorb power to increase the fluid pressure or head (ducted and unducted fans, compressors, and pumps) and those that produce power by expanding fluid to a lower pressure or head (wind, hydraulic, steam, and gas turbines). Methods of analyzing the flow processes differ depending upon the geometrical configuration of the machine. The most fundamental and valuable principles in fluid mechanics is Newton's second law of motion. The momentum equation relates the sum of the external forces acting on a fluid element to its acceleration, or to the rate of change of momentum in the direction of the resultant external force. The chapter presents the basic physical laws of fluid mechanics and thermodynamics, developing them into a form suitable for the study of turbomachines such as the continuity of flow equation, the first law of thermodynamics and the steady flow energy equation, the momentum equation, and the second law of thermodynamics. The energy and entropy equations are introduced in the chapter, along with all-important Euler work equation, which applies to all turbomachines. It also presents important efficiencies such as efficiency of turbines, steam and gas turbines, hydraulic turbines, and compressors and pumps.

Publisher Summary The chapter emphasizes on the dimensional analysis and performance law associate with turbomachines. The widest comprehension of the general behavior of all turbomachines is obtained from dimensional analysis. Dimensional analysis applied to turbo machines has two uses—namely, prediction of a prototype's performance from the tests conducted on a scale model (similitude) and the determination of the most suitable type of machine on the basis of maximum efficiency, for a specified range of head, speed, and flow rate. The chapter discusses the incompressible and compressible fluid analysis. In case of incompressible fluid analysis, the performance of a turbo machine can be expressed in terms of the control variables, geometric variables, and fluid properties. The application of dimensional analysis to compressible flow increases the complexity of the functional relationships such as flow coefficient and stage loading. Performance characteristics for high speed machines such as compressor and turbines are also discussed in the chapter. A useful guide to the selection of the most appropriate type and size of compressor, pump or fan for a given duty and optimum efficiency is obtained by means of the cordier diagram.

Publisher Summary This chapter presents the basic thermodynamic and aerodynamic characteristics of axial-flow turbines. It covers the preliminary design and analysis of single- and multi-stage axial turbines. The main goal in the preliminary stage design of a turbine is to fix the shapes of the velocity triangles, either by setting the flow angles or by choosing values for the three dimensionless design parameters—φ, ψ, and R. A consideration of the ways the preliminary design choices affect the turbine basic layout and the efficiency can provide useful guidance to the designer .The development of the axial-flow turbine clearly depends upon the design advances made in the field of steam turbines. Three key non-dimensional parameters such as design flow coefficient, stage loading coefficient, and stage reaction are related to the shape of the turbine velocity triangles and are used in fixing the preliminary design of a turbine stage. The calculations needed to fix the size, the number of stages, the number of aerofoils in each blade row, and the velocity triangles are covered in the chapter. It covers the merits of different styles of turbine design including the implications for mechanical design such as centrifugal stress levels and cooling in high speed and high temperature turbines. Through the use of some relatively simple correlations, the trends in turbine efficiency with the main turbine parameters are also presented in the chapter.

Enabling technologies are being developed at Sandia National Laboratories to improve the performance and flexibility of compact pulsed power drivers for magnetically driven dynamic materials properties research. We have designed a modular system capable of precision current pulse shaping through the selective triggering of pulse forming components into a disk transmission line feeding a strip line load. The system is comprised of two hundred and forty 200 kV, 60 kA modules in a low inductance configuration capable of producing 250–350 kbar of magnetic pressure in a 1.75 nH, 20 mm wide strip line load. The system, called Genesis, measures approximately 5 meters in diameter and is capable of producing shaped currents greater than 5 MA. This performance is enabled through the use of a serviceable solid dielectric insulator system which minimizes the system inductance and reduces the stored energy and operating voltage requirements. Genesis can be programmed by the user to generate precision pulse shapes with rise times of 220–500 ns, allowing characterization of a range of materials from tungsten to polypropylene. This paper provides an overview of the Genesis design including the use of genetic optimization to shape currents through selective module triggering.

Toxoplasma gondii was isolated from the brain of a young dog for the first time in Australia. The identity of the parasite was confirmed by PCR, Western blotting, electron microscopy and cat bioassay. Genotyping of the isolate (TgDgAu1) was determined by PCR-RFLP markers that showed it to be a Type II strain. Western blotting demonstrated the presence of IgM antibodies to T. gondii suggesting the bitch was probably infected during pregnancy and the T. gondii was transmitted to the pups congenitally. We believe this represents the first description of a natural case of congenital transmission of T. gondii in the dog. © 2009 Elsevier B.V.

To demonstrate the clinical and reproductive safety in rams of repetitive oral doses of monepantel, an amino-acetonitrile derivative (AAD), when administered at three times the proposed maximum recommended dose (MRD) over an entire spermatogenic cycle and during mating with ewes.A randomised controlled blinded study design was used with 28 rams randomly divided into two groups. The control group was treated with saline, and the other group was given three times the MRD (11.25 mg/kg) of monepantel. Treatments were administered orally every 5 days, for 100 days, during an entire spermatogenic cycle and subsequent mating period. Detailed recording at multiple time points were made of veterinary examinations; observations for adverse events; bodyweight measurements; faecal scores; haematology, clinical chemistry and coagulation variables; semen indices; evaluation of serving capacity; and gross pathology (including measurement of organ weights) performed on 10 rams from each group at the completion of the study.All rams treated with monepantel and those in the control group thrived and behaved normally to the end of the study. No treatment-related, toxicologically relevant adverse events, clinical observations or macroscopic changes were observed. Furthermore, there were no significant differences in bodyweight or organ weights, and haematological, clinical chemistry or coagulation variables between rams treated with monepantel and control rams. No significant changes were observed in any semen variable measured in any rams, and the serving capacity of rams mated to ewes was unaffected.Repeated oral administration of monepantel at three times the MRD every 5 days over an entire spermatogenic cycle and during mating was not associated with any treatment-related adverse effects on the reproductive performance of rams and was systemically very well tolerated. This study demonstrated that this population of rams could tolerate accidental overdoses of up to three times the MRD of monepantel or prolonged repetitive administration at overdoses. Thus, those so treated entering a breeding programme would have normal sperm indices, mating behaviour, and health.

Avian thymic hormone (ATH), a parvalbumin with immunomodulating properties, was used as antigen for development of a hybridoma cell line. Hybridoma screening by enzyme-linked immunosorbent assay (ELISA) led to the culture, purification, and characterization of an hybridoma, designated 4A6, which secretes IgG1 that is specific for ATH. The monoclonal antibody (MAb) was characterized by techniques involving indirect competitive and non-competitive ELISA, Western Blot analysis, and immunohistological staining. The MAb was highly specific for ATH with no cross-reactivity to other chicken tissue extracts or commercially available parvalbumins.

High-energy photons and electrons on the Sandia National Laboratories “Z” accelerator, a z-pinch device, will deposit energy into a capsule and fuel; this may create a potential preheat problem for inertial confinement infusion (ICF). In this article we discuss heating of the capsule and fuel by high-energy photons and electrons. The fuel is heated to

To meet long-term needs, many veterinary colleges and schools are participating in dual-degree DVM/MPH programs. Auburn University's College of Veterinary Medicine and the School of Public Health at the University of Alabama at Birmingham have developed a coordinated-degree curriculum in which the DVM and the MPH are not necessarily awarded simultaneously. Other opportunities at Auburn include Public Health Careers Day, trips to the Centers for Disease Control and Prevention, several elective courses related to veterinary epidemiology, and online access to the Emerging and Exotic Diseases of Animals course available from the Veterinary Information Network. We have been able to increase our students’ exposure to the role of the veterinarian in public health and to develop a program to augment their training in public practice.

Summary form only given. Veloce is a medium-voltage, high-current, compact pulsed power generator developed for cost effective isentropic and shock compression experiments at Sandia National Laboratories. It is based on a strip line design where no oil, water, and vacuum are used for insulation, thus making it easy to operate and maintain. The machine delivers up to 3 MA of current rapidly (~ 440-530 ns) into an inductive load where significant magnetic pressures are produced. The resulting magnetic pressure can be used either to drive ramp pressure waxes (peak pressures up to 12 GPa) into material samples or to launch a flyer plates to high velocities (1-4 km/s). Because of its lower cost per shot and greater availability, Veloce is well suited for studying isentropic compression experiments (ICE) in much greater detail than previously allowed in larger pulsed power machines. Several key issues in ICE, such as panel and sample preparation, uniformity of loading, and edge effects, have been examined extensively on Veloce. In addition, magnetic hydrodynamic simulations using the Alegra code have been performed to interpret the experimental results.