Download or read book Theoretical Modelling of Aeroheating on Sharpened Noses Under Rarefied Gas Effects and Nonequilibrium Real Gas Effects written by Zhi-Hui Wang and published by Springer. This book was released on 2014-08-28 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theoretical Modelling of Aeroheating on Sharpened Noses under Rarefied Gas Effects and Nonequilibrium Real Gas Effects employs a theoretical modeling method to study hypersonic flows and aeroheating on sharpened noses under rarefied gas effects and nonequilibrium real gas effects that are beyond the scope of traditional fluid mechanics. It reveals the nonlinear and nonequilibrium features, discusses the corresponding flow and heat transfer mechanisms, and ultimately establishes an analytical engineering theory framework for hypersonic rarefied and chemical nonequilibrium flows. The original analytical findings presented are not only of great academic significance, but also hold considerable potential for applications in engineering practice. The study explores a viable new approach, beyond the heavily relied-upon numerical methods and empirical formulas, to the present research field, which could be regarded as a successful implementation of the idea and methodology of the engineering sciences.
Download or read book Unified Theoretical Foundations of Lift and Drag in Viscous and Compressible External Flows written by Luo-Qin Liu and published by Springer. This book was released on 2017-09-29 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis analyzes aerodynamic forces in viscous and compressible external flows. It is unique, as the force theories discussed apply to fully viscous and compressible Navier-Stokes external flows, allowing them to be readily combined with computational fluid dynamics to form a profound basis of modern aerodynamics. This thesis makes three fundamental contributions to theoretical aerodynamics, presenting: (1) a universal far-field zonal structure that determines how disturbance flow quantities decay dynamically to the state of rest at infinity; (2) a universal and exact total-force formula for steady flow and its far-field asymptotics; and (3) a general near-field theory for the detailed diagnosis of all physical constituents of aerodynamic force and moment.
Download or read book An Investigation of Real Gas Effects in Supercritical CO2 Compressors written by Nikola Dimitrov Baltadjiev and published by . This book was released on 2012 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents a comprehensive assessment of real gas effects on the performance and matching of centrifugal compressors operating with CO2 at supercritical conditions. The analytical framework combines first principles based modeling with targeted numerical simulations to characterize the internal flow behavior of supercritical fluids with implications for turbomachinery design and analysis. Trends in gas dynamic behavior, not observed for ideal fluids, are investigated using the influence coefficients for compressible channel flow derived for real gas. The variation in the properties of CO2 and the expansion through the vapor-pressure curve due to local flow acceleration are identified as possible mechanisms for performance and operability issues observed near the critical point. The performance of a centrifugal compressor stage is assessed at different thermodynamic conditions relative to the critical point using high fidelity simulations. The results indicate a reduction of 9% in the choke margin of the stage compared to its performance at ideal gas conditions due to variations in real gas properties. Compressor stage matching is also impacted by real gas effects as the excursion in corrected mass flow per unit area from inlet to outlet increases by 5%. Investigation of the flow field near the impeller leading edge at high flow coefficients shows that local flow acceleration causes the thermodynamic conditions to reach the vapor-pressure curve. The significance of two-phase flow effects is determined through a non-dimensional parameter that relates the time required for liquid droplet formation to the residence time of the flow under saturation conditions. Applying this criterion to the candidate compressor stage shows that condensation is not a concern at the investigated operating conditions. In the immediate vicinity of the critical point however, this effect is expected to become more prominent. While the focus of this analysis is on supercritical CO2 compressors for carbon capture and sequestration, the methodology is directly applicable to other non-conventional fluids and applications. Experimental work is proposed to validate the key concepts and findings of this thesis.
Download or read book Aerodynamic Heating Using the Real Properties of Air Behind Shock Waves written by R. K. Livett and published by . This book was released on 1958 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report discusses the development of a procedure for determining flow properties behind conical and oblique shocks which has a short computation time. This was accomplished by curve fitting shock properties. The necessity of using real gas properties in determining post shock properties is illustrated by comparing the real gas solutions to the perfect gas solutions. In addition the effect of using real versus perfect shock gas properties in determining heat transfer is illustrated by comparing equilibrium skin temperatures computed using the two different post shock property solutions. From this study it was found that though there is considerable difference between real and perfect gas shock properties, this difference is not sufficient to cause large differences in equilibrium surface temperatures.
Download or read book Heat Addition to a One dimensional Supersonic Flow Including Real Gas Effects written by Serge Albert Waiter and published by . This book was released on 1960 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thermodynamic study of heat addition process in a supersonic flow is presented, taking account of the effects of dissociation and ionization; the only hypothesis proposed is that the flow is in thermodynamic equilibrium at each point. The specific mechanism of the heat source is not given in detail in this paper, but, it will be supposed that the heat added to the system is steady and constant per unit distance along the nozzle axis. With these assumptions, this problem can be solved in all the simple cases previously treated; for instance: (a) Constant Mach number heating process (accelerating flow), (b) Constant pressure heating process (constant speed flow), (c) Constant area heating process (decelerating flow). In each of these cases, the solution will be obtained by the use of a Mollier diagram (Enthalpy versus Entropy), pointing out all the thermodynamic characteristics of the mixture during heating. Whereas in the case of perfect gases, heating at constant Mach number seems to be quite satisfactory, the results obtained for real gases show some superiority for the heating at constant pressure. The heating at constant area is to be rejected because of the Mach numbers obtained at the end of heating which are, in all cases, low subsonic. The use of the Mollier diagram points out an important parameter, the final static temperature of the test section.
Download or read book Basics of Aerothermodynamics written by Ernst Heinrich Hirschel and published by Springer Science & Business Media. This book was released on 2006-01-16 with total page 419 pages. Available in PDF, EPUB and Kindle. Book excerpt: The last two decades have brought two important developments for aeroth- modynamics. One is that airbreathing hypersonic flight became the topic of technology programmes and extended system studies. The other is the emergence and maturing of the discrete numerical methods of aerodyn- ics/aerothermodynamics complementary to the ground-simulation facilities, with the parallel enormous growth of computer power. Airbreathing hypersonic flight vehicles are, in contrast to aeroassisted re-entry vehicles, drag sensitive. They have, further, highly integrated lift and propulsion systems. This means that viscous eflFects, like boundary-layer development, laminar-turbulent transition, to a certain degree also strong interaction phenomena, are much more important for such vehicles than for re-entry vehicles. This holds also for the thermal state of the surface and thermal surface effects, concerning viscous and thermo-chemical phenomena (more important for re-entry vehicles) at and near the wall. The discrete numerical methods of aerodynamics/aerothermodynamics permit now - what was twenty years ago not imaginable - the simulation of high speed flows past real flight vehicle configurations with thermo-chemical and viscous effects, the description of the latter being still handicapped by in sufficient flow-physics models. The benefits of numerical simulation for flight vehicle design are enormous: much improved aerodynamic shape definition and optimization, provision of accurate and reliable aerodynamic data, and highly accurate determination of thermal and mechanical loads. Truly mul- disciplinary design and optimization methods regarding the layout of thermal protection systems, all kinds of aero-servoelasticity problems of the airframe, et cetera, begin now to emerge.
Download or read book High speed Wind Tunnels written by Luigi Crocco and published by . This book was released on 1946 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance assumed in recent times by experimental supersonic wind tunnels, as well as the power required, has brought about the need for a study which would permit a comparison of the types tested and the principal theoretical plans.
Download or read book Incompressible Flow written by Ronald L. Panton and published by John Wiley & Sons. This book was released on 2013-08-05 with total page 912 pages. Available in PDF, EPUB and Kindle. Book excerpt: The most teachable book on incompressible flow— now fully revised, updated, and expanded Incompressible Flow, Fourth Edition is the updated and revised edition of Ronald Panton's classic text. It continues a respected tradition of providing the most comprehensive coverage of the subject in an exceptionally clear, unified, and carefully paced introduction to advanced concepts in fluid mechanics. Beginning with basic principles, this Fourth Edition patiently develops the math and physics leading to major theories. Throughout, the book provides a unified presentation of physics, mathematics, and engineering applications, liberally supplemented with helpful exercises and example problems. Revised to reflect students' ready access to mathematical computer programs that have advanced features and are easy to use, Incompressible Flow, Fourth Edition includes: Several more exact solutions of the Navier-Stokes equations Classic-style Fortran programs for the Hiemenz flow, the Psi-Omega method for entrance flow, and the laminar boundary layer program, all revised into MATLAB A new discussion of the global vorticity boundary restriction A revised vorticity dynamics chapter with new examples, including the ring line vortex and the Fraenkel-Norbury vortex solutions A discussion of the different behaviors that occur in subsonic and supersonic steady flows Additional emphasis on composite asymptotic expansions Incompressible Flow, Fourth Edition is the ideal coursebook for classes in fluid dynamics offered in mechanical, aerospace, and chemical engineering programs.
Download or read book Aerodynamic Principles of Flight Vehicles written by A. G. Panaras and published by AIAA (American Institute of Aeronautics & Astronautics). This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In "Aerodynamic Principles of Flight Vehicles" Argyris Panaras examines the fundamentals of vortices and shock waves, aerodynamic estimation of lift and drag, airfoil theory, boundary layer control, and high-speed, high-temperature flow. Individual chapters address vortices in aerodynamics, transonic and supersonic flows, transonic/supersonic aircraft configurations, and high-supersonic/hypersonic flows, beginning with definitions and historical data, and then describing present-day status and current research challenges. Emphasis is given to flow control, to the evolution of flight vehicle shapes as flight speed has increased, and to discoveries that enabled breakthrough developments in flight. The book: examines why various equations and technologies were developed, explains major contributors in areas such as vortices and aircraft wakes, drag buildup, sonic boom, and shock wave-boundary layer interactions, among others, and helps readers apply concepts from the material to their own projects. Archival and encyclopedic, "Aerodynamic Principles of Flight Vehicles" is a superb reference for aeronautical students and professionals alike. Although most beneficial to readers with a working knowledge of aerodynamics, it is accessible to anyone with an introductory understanding of the field.
Download or read book Approximations for the Thermodynamic and Transport Properties of High temperature Air written by C. Frederick Hansen and published by . This book was released on 1958 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thermodynamic and transport prorerties of high-temperature air are found in closed form starting from approximate partition functions for the major components in air and neglecting all minor components. The compressibility, energy, entropy, the specific heats, the speed of sound, the coefficients of viscosity and of thermal conductivity, and the Prandtl numbers for air are tabulated from 500 degrees to 15,000 degrees K over a range of pressure from 0.0001 to 100 atmospheres. The enthalpy of air and the mol fractions of the major components of air can easily be found from the tabulated values for compressibility and energy. It is predicted that the Prandtl number for fully ionized air will become small compared to unity, the order of 0.01, and this implies that boundary layers in such flow will be very transparent to heat flux.
Download or read book The DSMC Method written by G. A. Bird and published by . This book was released on 2013-08-19 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: Direct Simulation Monte Carlo is a well-established method for the computer simulation of a gas flow at the molecular level. While there is a limit to the size of the flow-field with respect to the molecular mean free path, personal computers now allow solutions well into the continuum flow regime. The method can be applied to basic problems in gas dynamics and practical applications range from microelectromechanics systems (MEMS) to astrophysical flows. DSMC calculations have assisted in the design of vacuum systems, including those for semiconductor manufacture, and of many space vehicles and missions. The method was introduced by the author fifty years ago and it has been the subject of two monographs that have been published by Oxford University Press. It is now twenty years since the second of these was written and, since that time, most DSMC procedures have been superseded or significantly modified. In addition, visual interactive DSMC application programs have been developed that have proved to be readily applicable by non-specialists to a wide variety of practical problems. The computational variables are set automatically within the code and the programs report whether or not the criteria for a good calculation have been met. This book is concerned with the theory behind the current DSMC molecular models and procedures, with their integration into general purpose programs, and with the validation and demonstration of these programs. The DSMC and associated programs, including all source codes, can be freely downloaded through links that are provided in the book. The main accompanying program is simply called the "DSMC program" and, in future versions of the book, it will be applicable to homogeneous (or zero-dimensional) flows through to three-dimensional flow. All DSMC simulations are time-accurate unsteady calculations, but the flow may become steady at large times. The current version of the DSMC code is applicable only to zero and one-dimensional flows and the older DS2V code is employed for the two-dimensional validation and demonstration cases. It is because of this temporary use of the older and well-proven program that the DS2V source code is made freely available for the first time. Most of the homogeneous flow cases are validation studies, but include internal mode relaxation studies and spontaneous and forced ignition leading to combustion in an oxygen-hydrogen mixture. The one-dimensional cases include the structure of a re-entry shock wave that takes into account electronic excitation as well as dissociation, recombination and exchange reactions. They also include a spherically imploding shock wave and a spherical blast wave. The two-dimensional and axially-symmetric demonstration cases range from a typical MEMS flow to aspects of the flow around rotating planets. Intermediate cases include the formation and structure of a combustion wave, a vacuum pump driven by thermal creep, a typical vacuum processing chamber, and the flow around a typical re-entry vehicle
Download or read book A First order Green s Function Approach to Supersonic Oscillatory Flow A Mixed Analytic and Numeric Treatment written by and published by . This book was released on 1985 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nonequilibrium Flows written by Peter P. Wegener and published by . This book was released on 1969 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hypersonic Aerothermodynamics written by John J. Bertin and published by AIAA. This book was released on 1994 with total page 644 pages. Available in PDF, EPUB and Kindle. Book excerpt: A modern treatment of hypersonic aerothermodynamics for students, engineers, scientists, and program managers involved in the study and application of hypersonic flight. It assumes an understanding of the basic principles of fluid mechanics, thermodynamics, compressible flow, and heat transfer. Ten chapters address: general characterization of hypersonic flows; basic equations of motion; defining the aerothermodynamic environment; experimental measurements of hypersonic flows; stagnation-region flowfield; the pressure distribution; the boundary layer and convective heat transfer; aerodynamic forces and moments; viscous interactions; and aerothermodynamics and design considerations. Includes sample exercises and homework problems. Annotation copyright by Book News, Inc., Portland, OR
Download or read book Hypersonic Airbreathing Propulsion written by William H. Heiser and published by AIAA. This book was released on 1994 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: An almost entirely self-contained engineering textbook primarily for use in undergraduate and graduate courses in airbreathing propulsion. It provides a broad and basic introduction to the elements needed to work in the field as it develops and grows. Homework problems are provided for almost every individual subject. An extensive array of PC-based user-friendly computer programs is provided in order to facilitate repetitious and/or complex calculations. Annotation copyright by Book News, Inc., Portland, OR
Download or read book New Results in Numerical and Experimental Fluid Mechanics IX written by Andreas Dillmann and published by Springer Science & Business Media. This book was released on 2014-01-25 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents contributions to the 18th biannual symposium of the German Aerospace Aerodynamics Association (STAB). The individual chapters reflect ongoing research conducted by the STAB members in the field of numerical and experimental fluid mechanics and aerodynamics, mainly for (but not limited to) aerospace applications, and cover both nationally and EC-funded projects. By addressing a number of essential research subjects, together with their related physical and mathematics fundamentals, the book provides readers with a comprehensive overview of the current research work in the field, as well as its main challenges and new directions. Current work on e.g. high aspect-ratio and low aspect-ratio wings, bluff bodies, laminar flow control and transition, active flow control, hypersonic flows, aeroelasticity, aeroacoustics and biofluid mechanics is exhaustively discussed here.
Download or read book Thesaurus of Engineering and Scientific Terms written by Engineers Joint Council and published by . This book was released on 1967 with total page 708 pages. Available in PDF, EPUB and Kindle. Book excerpt:
