bluuebunny/crossref_metadata_2025_split huggingface dataset:
Serological evidence of lack of contact with caprine herpesvirus type 1 and bluetongue virus in goat population in Poland
Authors: Czopowicz M. , Kaba J. , Szaluś-Jordanow O. , Nowicki M. , Witkowski L. , Frymus T. 
Published: December 2010

Serological evidence of lack of contact with caprine herpesvirus type 1 and bluetongue virus in goat population in PolandInvestigation into herd-level seroprevalence of caprine herpesvirus type 1 (CpHV-1) and bluetongue virus (BTV) was conducted in 2007 in Poland. It involved the entire population of goats covered by a milk recording program in 2007, which included 49 goat herds. The number of goats examined in each herd was determined statistically in order to detect the presence of at least one seropositive animal in a herd with a 95% probability and simple random method of sampling was applied. No antibodies to CpHV-1 or BTV were detected. Further calculations were carried out to determine the herd-level true seroprevalence, taking into account sensitivity and specificity of the test as well as several other factors. It can be concluded that till the middle of 2007 population of Polish goats covered by the milk recording program remained negative with respect to CpHV-1 and BTV.
Molecular characterization of Polish Prototheca zopfii mastitis isolates and first isolation of Prototheca blaschkeae in Poland
Authors: Jagielski T. , Lassa H. , Ahrholdt J. , Roesler U. , Malinowski E. 
Published: December 2010

Molecular characterization of Polish Prototheca zopfii mastitis isolates and first isolation of Prototheca blaschkeae in Poland
Bovine mastitits caused by the colorless, yeast-like alga Prototheca zopfii is a serious and complex condition that results in heavy economic losses in the dairy industry, both through a substantial reduction in milk production and culling of infected animals. Based on the 18S rDNA sequence analysis, genotype-specific PCR assays have recently been developed to differentiate within the species P. zopfii three distinct P. zopfii genotypes (1-3), of which P. zopfii genotype 3 has been considered a new species P. blaschkeae sp. nov. The purpose of this study was to employ the newly-devised molecular approach for the detection of the two P. zopfii genotypes and P. blaschkeae sp. nov. among bovine mastitis isolates from Poland. This study is the first to provide molecular characterization of Polish P. zopfii mastitis isolates. It also gives the first description of bovine mammary protothecosis due to P. blaschkeae in Poland, as evidenced by genotypical, microbiological, and electron microscopy findings.
Influence of gastrointestinal trichostrongylidosis on ram fertility
Authors: Gaglio G. , Poglayen G. , Capelli G. , Gruner L. , Mara L. , Giannetto S. , Scala A. 
Published: December 2010

Influence of gastrointestinal trichostrongylidosis on ram fertility
A study on the influence of gastrointestinal trichostrongyles on ram fertility was performed. Two groups of semen donor rams (Sarda breed) were utilized; one was experimentally infected with Haemonchus contortus, Trichostrongylus colubriformis and Teladorsagia circumcincta and the other was used as a control group. In all animals, coprological, haematological and reproductive parameters were studied. The results suggest that the parasites had a limited effect with some changes in phosphorus, cholesterol and chlorine levels. In our experience the parasitic burden produced no significant change on ram fertility.
High Angle of Attack Aerodynamics
Authors: Gursul Ismet , Wang Zhijin 
Published: December 2010

AbstractIn this chapter, low‐speed aerodynamics of highly swept wings is discussed. Highly swept wings, known asdeltawings, can fly at high angle of attack without stall. This quality is invaluable for military aircraft during a high angle of attack maneuver. Leading‐edge vortices develop on highly swept wings as a result of flow separation and contribute to the lift force. Highly energetic vortices break down or burst at high angles of attack, resulting in highly unsteady flows. Vortex breakdown may cause wing or fin vibrations, called buffeting, which is the structural response due to the unsteady flow. Aircraft configurations may have forebody vortices, leading‐edge vortices that originate from strakes, and the main wing vortices, which may interact with each other during a maneuver. Leading‐edge vortices in unsteady flows exhibit substantial time lag and hysteresis effects. They may also cause self‐induced roll oscillations of aircraft, known as wing rock. Finally, vortex control techniques are briefly discussed.
Missile Aerodynamics
Authors: Platzer Max F. 
Published: December 2010

AbstractIn this chapter, the aerodynamics of bodies of revolution, low‐aspect‐ratio wings, and wing–body combinations is discussed. Typical projectiles and missiles reach subsonic, transonic, or supersonic flight speeds, and the angle of attack may vary over a substantial range. Therefore, the major phenomena caused by compressible or viscous flow effects such as wave drag, flow separation, and vortex generation, need to be part of this discussion. It is shown that the aerodynamics of slender missile configurations flying at zero or small angles of attack can be described by a relatively simple inviscid flow theory, called slender body theory. At zero angle of attack, the flow is composed of two contributions: a flow in planes perpendicular to the flight direction, the so‐called cross flow, and a flow that depends only on the variation of the missile cross section in the flight direction. This recognition leads to the equivalence or area rule that states that the transonic/supersonic wave drag is the same for missiles with equal cross‐sectional area distributions. This same slender body theory also leads to the recognition that the lifting forces on missiles flying at small angle of attack depend only on the cross flow. In contrast, the flow generated by missiles flying at large angles of attack is very complex due to strong vortices shed from the missile body and wings, requiring the solution of the full three‐dimensional viscous flow equations.
Rotorcraft Aerodynamics
Authors: Leishman J. Gordon 
Published: December 2010

Abstract
Helicopters and other types of rotorcraft have become an indispensable part of modern aviation. Such aircraft are capable of taking off and landing vertically from almost any surface, although this capability comes at a significant price, including higher power requirements for flight and the eventual onset of several aeromechanical “barrier” problems that limit flight performance. This chapter reviews the basic methods used for the aerodynamic analysis of rotary wings, primarily as applied to helicopter rotors, and exposes the fundamental performance characteristics of helicopters during hovering, climbing, descending, and forward flight. While classical methods for analysis such as momentum theory and blade element theory still have much value for the purposes of design and performance analysis, research is leading to advanced aerodynamic methods that will help to further understand and mitigate the various aeromechanical problems that are encountered on rotorcraft.
Low Reynolds Number Aerodynamics of Fixed Wings
Authors: Mueller Thomas J. , Pelletier Alain 
Published: December 2010

AbstractInterest in the design of small, efficient, radio‐controlled aircraft began with model airplanes in the 1930s and continues to this day because of the developments in sensors and actuators for a wide variety of small unmanned aerial vehicles. The combination of small scale and low velocities results in a flight regime with low chord Reynolds numbers. The range of chord Reynolds number from about 60000 to 200000 is of particular interest. The design of airfoils in the low Reynolds number regime and the experimental validation of these designs are discussed in this chapter. The design and performance of low aspect ratio (LAR) wings for micro air vehicle (MAV) applications including the effect of camber have been discussed. Examples of the application of LAR wings to the design of rigid and flexible fixed wing MAVs are presented.
Aircraft Wake Vortices
Authors: Jacquin Laurent 
Published: December 2010

AbstractTrailing vortices are an unavoidable and potentially harmful by‐product of fixed‐wing aircraft and can persist for many miles behind the vehicle. The imposition of trailing‐vortex airplane‐separation requirements in 1970 has been a catalyst for significant advances in vortex dynamics – a fundamental discipline at the crossroads of mechanics and physics. A heightened interest in the field came about in the 1990s, motivated by the need to improve airport throughput and by the introduction of a new giant aircraft, the A380. This has stimulated new studies seeking to predict and/or control the natural development of the vortices. This chapter aims to provide the reader with basic notions on fluid mechanics, vortex dynamics, and aerodynamics, which are necessary to appraise both the fundamental and practical facets of the topic. Recent wake vortex research has benefited considerably from concurrent analytical, numerical, and experimental research, and we used results from these different domains to exemplify the concepts. The chapter ends with a short summary on current research and on perspectives of the topic.
Complex Internal Compressible Flows
Authors: Kontis Konstantinos , Jagadeesh Gopalan , Srisha Rao M.V. 
Published: December 2010

AbstractThe control volume approach, if appropriately applied, can yield information on the dependencies among various variables on compressible flow systems, which is very useful for parametric studies. The complex internal compressible flows presented here fall into the following categories: steady flows through variable area ducts with and without heat addition and friction, nozzle starting and choking, shock trains, shock tubes, and unsteady flows inside angled‐bend ducts. Ram/Scram jet engines and ejectors are described, as they are representative examples of complex flow systems.
External Transonic Flows
Authors: Lawson Nicholas J. 
Published: December 2010

AbstractTransonic flows are found across many aerodynamic applications. This chapter reviews fundamental aspects of external transonic flow aerodynamics and swept wing design. Initially, simple inviscid approximations are introduced to account for transonic effects and then the typical flow features found on actual 2D transonic aerofoils are outlined where the effect of viscosity is shown to have a significant effect on the flow field. The chapter also introduces the advantages of swept wing design but emphasizes the flow complexities present on actual swept wings. These are due to a combination of 3D flow effects and shock modification on the wing, which requires complex 3D treatment to remove.
Complex Shock Wave Phenomena
Authors: Rider William J. 
Published: December 2010

AbstractComplexity in shock wave phenomena arises in almost every natural or technological system with shock waves. Shock waves are responsible for some of the most beautiful structures in the universe as well as some of the most destructive creations of mankind. Even the most basic shock wave phenomena are fundamentally nonlinear in nature, thus rendering it difficult to subject to precise analysis. Nonetheless, the basic phenomena are best understood by breaking the complex system of shocks into simpler pieces more amenable to study including analysis, simulation, observations, and experiments. Modern practice in computational science can integrate each of these elements together via verification and validation to quantify our understanding and assist advances in our knowledge.
Fundamentals of Compressible Turbulent Mixing
Authors: Yoder Dennis A. , Georgiadis Nicholas J. 
Published: December 2010

AbstractThis chapter provides a brief introduction to the fundamentals of compressible turbulent mixing in flows such as jets and mixing layers, which are of considerable importance in aerospace applications. Two key changes are found to occur when these types of flows are compressible: (i) the shear layer growth rate is reduced compared with incompressible flow, and (ii) the turbulence structure becomes altered. While several theories have been proposed for why these changes occur, the current belief is that the propagation of pressure fluctuations is hindered by the finite speed of sound in a compressible medium. This reduced communication across the shear layer disrupts the natural agglomeration of turbulent eddies.
Unsteady Transonic Aerodynamics
Authors: Platzer Max F. 
Published: December 2010

AbstractAt flight speeds close to the speed of sound unique unsteady aerodynamic and aeroelastic phenomena are encountered. It is the objective of this chapter to provide an overview of the unsteady transonic flow phenomena and the flight mechanical and aeroelastic problems they may cause. The most prominent ones are wing rock and wing drop, buffeting, control surface buzz, flutter and limit cycle oscillations. An overview is also given of the current status of analysis methods to predict these phenomena.
Introduction to Hypersonic Flow
Authors: Gaitonde Datta V. 
Published: December 2010

AbstractThis chapter introduces the main aerodynamic physical phenomena encountered in hypersonic flow. The vehicle environment is first set into context by examining flight paths of typical vehicles, for missions from ballistic to access‐to‐space. The principal engineering problems arising in the harsh environment are outlined together with preliminary considerations on the manner in which these impact the mission‐dependent shape of the vehicle. The physics of high‐speed flow are introduced by first discussing strong inviscid and viscous interactions encountered at higher Mach numbers. This is followed by a brief description of some of the most striking features distinguishing hypersonic from supersonic flow. These include high‐altitude low‐density effects that need recourse to molecular dynamics, thermo‐chemistry effects that are triggered at high temperatures and enthalpies, the effects of ablation for thermal protection, the potential impact of thermal radiation, and the newly energized field of flow control with natural or artificially enhanced ionization.
Analytical Foundation of Hypersonic Flow
Authors: Shang Joseph J.S. 
Published: December 2010

Abstract
Classical hypersonic theories are summarized for both inviscid and viscous flows. Theoretical developments are derived in the continuum regime, with focus on the systematic approximations that have been developed from the characteristics of hypersonic flow. These theories describe some of the most important hypersonic flow observations with relatively simple analysis. However, the effects of internal degrees of freedom of molecules are not considered, and thus the detailed treatment of the phenomena of rarefied flow, real gas effects, and radiation are excluded here.
Non‐Continuum Phenomena in Hypersonic Flow
Authors: Boyd Iain D. 
Published: December 2010

AbstractAt high altitude in the trajectory of a hypersonic entry vehicle, the atmospheric density is low, leading to relatively infrequent intermolecular collisions. The low collision rate produces physical flow phenomena which cannot be predicted accurately using a continuum description. This chapter describes the most important of these non‐continuum phenomena for hypersonic flow analysis and the conditions under which they occur. A numerical technique for analysis of non‐continuum flows is described and its success demonstrated through comparison with measurements collected in laboratory and flight experiments, and with results generated using the continuum approach.
Engineering Analysis of Heat Transfer
Authors: Klausner James F. 
Published: December 2010

Abstract
As was discussed in the Volume 1, Chapter 37, thermal energy transport can be quite complex and typically involves multimode heat transfer. In order to provide useful tools for engineering designers to analyze multimode heat transfer problems, idealizations and simplifications are necessary so that the dominant direction and mode of energy flow can be captured. Concepts such as thermal resistance and thermal circuits are thus very useful for analyzing such problems in conjunction with the energy conservation principle as will be discussed. In addition, these ideas will be extended to analyze heat transfer equipment using the log mean temperature difference (LMTD) and the number of transfer units (NTU).
Verification and Validation of
CFD
Based Turbulent Flow Experiments
Authors: Grinstein Fernando F. 
Published: December 2010

Abstract

Accurate predictions with quantifiable uncertainty are essential to many practical flow applications exhibiting extreme geometrical complexity and broad ranges of length and time scales. Under‐resolved computer studies are typically unavoidable in such applications. Critical issues involved in the flow experiments based on computational fluid dynamics relate to the treatment of unresolved
subgrid
scale flow features and required initial and boundary condition
supergrid
scale modeling. Flow characterization issues become very challenging ones in validation exercises based on laboratory data where potential sources of discrepancies between predictions and measurements need to be clearly evaluated and controlled. A special focus of the discussion in this chapter is devoted to turbulent flows.
The inherently
intrusive nature of numerical and laboratory turbulent flow experiments is noted in this context
.
Riemann Solvers in Aerospace Engineering
Authors: Toro Eleuterio F. 
Published: December 2010

AbstractThe Riemann problem is first explained in the setting of finite volume methods and solution approaches are then reviewed, ending with a detailed description of a particular solver as applied to the three‐dimensional Euler equations for compressible multicomponent flow. A number of related issues are briefly discussed and key references for further study are given.
Grid Generation Techniques
Authors: Soni Bharat K. , Shih Alan M. , Ito Yasushi 
Published: December 2010

AbstractThe grid generation (or mesh generation) process is a critical yet challenging step in the simulations that solve numerically nonlinear partial differential equations (PDEs) representative of fluid dynamics. It is often a tedious and labor‐intensive process when complex geometries are involved. There are many techniques in the grid generation process. In this chapter, concepts, strategies, algorithms, and software tools employed in the grid generation process are described. A brief outline of the grid generation process and adaptive grid generation is presented. Structured grid systems with Cartesian and curvilinear strategies and unstructured grid systems with quadtree/octree, Delaunay triangulation, advancing front, and advancing layers methods are summarized to provide readers with a clear overview of these important approaches. Software tools and literature sources for further information on grid generation techniques and applications are stated. In the final section, future trends in grid generation and technology vision are provided. Computational examples are presented throughout this chapter to demonstrate applications of grid strategies.
High Performance Computing forCFD
Authors: Garbey Marc 
Published: December 2010

AbstractThis chapter describes some general aspects of high performance computing in CFD. High performance computing has been dominated by commodity clusters with large number of cheap processors. These systems provide exceptional opportunity in performance to cost but bring numerous difficulties in designing numerically efficient parallel CFD solution. We will discuss successively hardware/software solution for CFD and reemphasize the importance of algorithm and software libraries.We will also discuss new opportunities in aerospace engineering brought by large parallel systems.
Reynolds‐Averaged Navier–Stokes Methods
Authors: Leschziner Michael A. 
Published: December 2010

AbstractRANS methods constitute the overwhelmingly dominant approach to computing the broad variety of flows that are pertinent to fluid‐engineering applications. Notwithstanding recent advances in Large Eddy Simulation (LES), this is set to remain the position for many years to come, mainly because of the stubbornly high computational costs of LES, especially in flows that are sensitive to the near‐wall turbulence structure. On the other hand, the RANS framework poses formidable challenges in respect of physical fidelity and generality, because its predictive characteristics hinge critically on complex turbulence models that involve extensive approximation and much intuition. This chapter provides an introductory review to the fundamentals of the RANS approach and the major classes of turbulence models used to approximate the Reynolds stresses – the correlations of turbulent velocity fluctuations that arise upon Reynolds‐averaging of the Navier–Stokes equations. The rationale of the models is outlined, the principal equations are included, and the main properties of the alternative models are discussed relative to other model types.
Large Eddy Simulation
Authors: Sagaut Pierre , Drikakis Dimitris 
Published: December 2010

AbstractThis article presents the current trends in modeling and simulation of transitional and turbulent flows using the state‐of‐the‐art of large eddy simulation (LES) computational strategies. The fundamentals of both the explicit and implicit LES strategies are presented followed by indicative examples showing the applicability of these approaches. Issues relating to numerical uncertainties and validation are also discussed.
Computational Modeling for Multiphase Flows, Including Microgravity and Space Applications
Authors: Shyy Wei , Sim Jaeheon 
Published: December 2010

Abstract
Multiphase flows involving moving interfaces between different fluids/phases are observed in nature as well as in a wide range of engineering applications. With the recent development of high‐fidelity computational techniques, a number of challenging multiphase flow problems around complex solid geometries can now be computed. We introduce the basic notion of the main categories of multiphase flow computational techniques and address issues arising from interface evolution in time with shape/topological changes, merger and breakup of objects such as drops or bubbles, and the steep fluid property and flow variable jumps across the phase boundary. We discuss Lagrangian, Eulerian, and Eulerian–Lagrangian techniques to represent and follow interface, and sharp and continuous interface methods to model interfacial dynamics. The marker‐based adaptive Eulerian–Lagrangian method, which is one of the most popular methods, is highlighted with microgravity flows and space applications including droplet collision and spacecraft liquid fuel tank sloshing and surface stability.