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The Final Proceedings for 21st International Symposium on Rarefied Gas Dynamics, 26 July 1998 - 31 July 1998. This is an interdisciplinary conference. Topics include Boltzman equation and kinetic theory; Mathematical methods and models; Flow in transitional and rarefied regimes; Numerical simulations of RGD flows; Instrumentation and diagnostics in RGD flows; Free jets and molecular beams; Elementary collisional processes; Transport and relaxation phenomena; Chemical processes; Shock waves; Low density plasmas and ionized gases; Gas-surface interactions; Molecular beams; Clusters; Aerosols; Phase change; Aerodynamics and aerothermochemistry of space vehicles; Industrial applications I (vacuum technology, thin film, microengines...); Industrial applications II (beams, jets, lasers, reactors...); Astrophysics; Environmental aspects.

The Final Proceedings for 21st International Symposium on Rarefied Gas Dynamics, 26 July 1998 - 31 July 1998. This is an interdisciplinary conference. Topics include Boltzman equation and kinetic theory; Mathematical methods and models; Flow in transitional and rarefied regimes; Numerical simulations of RGD flows; Instrumentation and diagnostics in RGD flows; Free jets and molecular beams; Elementary collisional processes; Transport and relaxation phenomena; Chemical processes; Shock waves; Low density plasmas and ionized gases; Gas-surface interactions; Molecular beams; Clusters; Aerosols; Phase change; Aerodynamics and aerothermochemistry of space vehicles; Industrial applications I (vacuum technology, thin film, microengines...); Industrial applications II (beams, jets, lasers, reactors...); Astrophysics; Environmental aspects.

The Final Proceedings for 21st International Symposium on Rarefied Gas Dynamics, 26 July 1998 - 31 July 1998. This is an interdisciplinary conference. Topics include Boltzman equation and kinetic theory; Mathematical methods and models; Flow in transitional and rarefied regimes; Numerical simulations of RGD flows; Instrumentation and diagnostics in RGD flows; Free jets and molecular beams; Elementary collisional processes; Transport and relaxation phenomena; Chemical processes; Shock waves; Low density plasmas and ionized gases; Gas-surface interactions; Molecular beams; Clusters; Aerosols; Phase change; Aerodynamics and aerothermochemistry of space vehicles; Industrial applications I (vacuum technology, thin film, microengines...); Industrial applications II (beams, jets, lasers, reactors...); Astrophysics; Environmental aspects.

The research supported by this grant was primarily on quasi-random sequences, which are a deterministic alternative to random or pseudo-random sequences', and their use in Monte Carlo methods, These methods are vastly superior to standard Monte Carlo, at least in principle, because the errors are of size O(N-1) rather than the usual O(N-1/).On the other hand, this gain in accuracy can be lost if the domain of integration is of high dimension or the function to be integrated is not smooth. In joint work with Bradley Moskowitz, we succeeded in overcoming these limitations for a number of Monte Carlo methods, including the acceptance-rejection method, Feynman-Kac integrals and diffusion Monte Carlo.

The research supported by this grant was primarily on quasi-random sequences, which are a deterministic alternative to random or pseudo-random sequences', and their use in Monte Carlo methods, These methods are vastly superior to standard Monte Carlo, at least in principle, because the errors are of size O(N-1) rather than the usual O(N-1/).On the other hand, this gain in accuracy can be lost if the domain of integration is of high dimension or the function to be integrated is not smooth. In joint work with Bradley Moskowitz, we succeeded in overcoming these limitations for a number of Monte Carlo methods, including the acceptance-rejection method, Feynman-Kac integrals and diffusion Monte Carlo.

We use the one-dimensional steady version of the equations derived in paper I to compute the structure of shock waves. The agreement with experiment is good, especially when we retain the experimental value of the Prandtl number adopted in II.

We use the one-dimensional steady version of the equations derived in paper I to compute the structure of shock waves. The agreement with experiment is good, especially when we retain the experimental value of the Prandtl number adopted in II.

We describe an asymptotic procedure for deriving continuum equations from the kinetic theory of a simple gas. As in the works of Hilbert, of Chapman and of Enskog, we expand in the mean flight time of the constituent particles of the gas, but we do not adopt the Chapman-Enskog device of simplifying the formulae at each order by using results from previous orders. In this way, we are able to derive a new set of fluid dynamical equations from kinetic theory, as we illustrate here for the relaxation model for monatomic gases. We obtain a stress tensor that contains a dynamical pressure term (or bulk viscosity) that is process-dependent and our heat current depends on the gradients of both temperature and density. On account of these features, the equations apply to a greater range of Knudsen number (the ratio of mean free path to macroscopic scale) than do the Navier-Stokes equations, as we see in the accompanying paper. In the limit of vanishing Knudsen number, our equations reduce to the usual Navier-Stokes equations with no bulk viscosity.

This document aims to provide information to the United States Air Force about the current status of research in rarefied gas dynamics and related fields, primarily via the 29th International Symposium on Rarefied Gas Dynamics (RGD29) held in Xi'an, China, July 13-18, 2014. The RGD Symposia take place every two years. They are a forum at which scientists and engineers report new developments in the field.

This document aims to provide information to the United States Air Force about the current status of research in rarefied gas dynamics and related fields, primarily via the 29th International Symposium on Rarefied Gas Dynamics (RGD29) held in Xi'an, China, July 13-18, 2014. The RGD Symposia take place every two years. They are a forum at which scientists and engineers report new developments in the field.

A high-speed rotating-cylinder apparatus is described for studying gas-surface interaction phenomena. The concrete enclosure is equipped with a hand-operated overhead hoist to handle the balance and drive mechanism prior to vacuum operation. During operation, measurements of drag, pressure, and rotor velocity can be made outside the enclosure. The instrument can be used to provide a shear flow field for the development of instrumentation for nonuniform streams or boundary layers. Initial tests indicated that the apparatus was satisfactory over a wide range of flow conditions from the continuum region (M/Re<1/100) to the free molecular flow region (M/rE<10).

A high-speed rotating-cylinder apparatus is described for studying gas-surface interaction phenomena. The concrete enclosure is equipped with a hand-operated overhead hoist to handle the balance and drive mechanism prior to vacuum operation. During operation, measurements of drag, pressure, and rotor velocity can be made outside the enclosure. The instrument can be used to provide a shear flow field for the development of instrumentation for nonuniform streams or boundary layers. Initial tests indicated that the apparatus was satisfactory over a wide range of flow conditions from the continuum region (M/Re<1/100) to the free molecular flow region (M/rE<10).

A high-speed rotating-cylinder apparatus is described for studying gas-surface interaction phenomena. The concrete enclosure is equipped with a hand-operated overhead hoist to handle the balance and drive mechanism prior to vacuum operation. During operation, measurements of drag, pressure, and rotor velocity can be made outside the enclosure. The instrument can be used to provide a shear flow field for the development of instrumentation for nonuniform streams or boundary layers. Initial tests indicated that the apparatus was satisfactory over a wide range of flow conditions from the continuum region (M/Re<1/100) to the free molecular flow region (M/rE<10).

Includes bibliographical references and indexes

Thesis (MS)--U.S. Naval Postgraduate School, 1963

Thesis (MS)--U.S. Naval Postgraduate School, 1963

The Final Proceedings for 21st International Symposium on Rarefied Gas Dynamics, 26 July 1998 - 31 July 1998. This is an interdisciplinary conference. Topics include Boltzman equation and kinetic theory; Mathematical methods and models; Flow in transitional and rarefied regimes; Numerical simulations of RGD flows; Instrumentation and diagnostics in RGD flows; Free jets and molecular beams; Elementary collisional processes; Transport and relaxation phenomena; Chemical processes; Shock waves; Low density plasmas and ionized gases; Gas-surface interactions; Molecular beams; Clusters; Aerosols; Phase change; Aerodynamics and aerothermochemistry of space vehicles; Industrial applications I (vacuum technology, thin film, microengines...); Industrial applications II (beams, jets, lasers, reactors...); Astrophysics; Environmental aspects.

This program is to develop an analytic method for reducing SUMS data for the determination of the undisturbed atmosphere conditions ahead of the shuttle along its descending trajectory. It is divided into an internal flow problem, an external flow problem and their matching conditions. Since the existing method of Direct Simulation Monte Carlo (DSMC) failed completely for the internal flow problem, the emphasis is on the internal flow of a highly non-equilibrium, rarefied air through a short tube of a diameter much less than the gaseous mean free path. A two fluid model analysis of this internal flow problem has been developed and studied with typical results illustrated. A computer program for such an analysis and a technical paper published in Lecture Notes in Physics No. 323 (1989) are included as Appendices 3 and 4. A proposal for in situ determination of the surface accommodation coefficients sigma sub t and sigma e is included in Appendix 5 because of their importance in quantitative data reduction. A two fluid formulation for the external flow problem is included as Appendix 6 and a review article for AIAA on Hypersonic propulsion, much dependent on ambient atmospheric density, is also included as Appendix 7.

Interplanetary space provides simultaneously the best vacuum available to man and, because of the solar wind, a tenuous and unsteady high-speed outflow of predominantly hydrogen gas from the sun, a remarkable variety of rarefied gasdynamics phenomena, to observe. A review is provided of these phenomena, and of the way in which the present level of understanding has been achieved.

Interplanetary space provides simultaneously the best vacuum available to man and, because of the solar wind, a tenuous and unsteady high-speed outflow of predominantly hydrogen gas from the sun, a remarkable variety of rarefied gasdynamics phenomena, to observe. A review is provided of these phenomena, and of the way in which the present level of understanding has been achieved.

Conference on transition flow, surface interactions, kinetic theory, molecular beams, internal flow, and rarified plasmas and shock structures

The Final Proceedings for 21st International Symposium on Rarefied Gas Dynamics, 26 July 1998 - 31 July 1998. This is an interdisciplinary conference. Topics include Boltzman equation and kinetic theory; Mathematical methods and models; Flow in transitional and rarefied regimes; Numerical simulations of RGD flows; Instrumentation and diagnostics in RGD flows; Free jets and molecular beams; Elementary collisional processes; Transport and relaxation phenomena; Chemical processes; Shock waves; Low density plasmas and ionized gases; Gas-surface interactions; Molecular beams; Clusters; Aerosols; Phase change; Aerodynamics and aerothermochemistry of space vehicles; Industrial applications I (vacuum technology, thin film, microengines...); Industrial applications II (beams, jets, lasers, reactors...); Astrophysics; Environmental aspects.

Recently a new class of Monte Carlo methods, called Time Relaxed Monte Carlo (TRMC), designed for the simulation of the Boltzmann equation close to fluid regimes have been introduced. A generalized Wild sum expansion of the solution is at the basis of the simulation schemes. After a splitting of the equation the time discretization of the collision step is obtained from the Wild sum expansion of the solution by replacing high order terms in the expansion with the equilibrium Maxwellian distribution; in this way speed up of the methods close to fluid regimes is obtained by efficiently thermalizing particles close to the equilibrium state. In this work we present an improvement of such methods which allows to obtain an effective uniform accuracy in time without any restriction on the time step and subsequent increase of the computational cost. The main ingredient of the new algorithms is recursivity. Several techniques can be used to truncate the recursive trees generated by the schemes without deteriorating the accuracy of the numerical solution. Techniques based on adaptive strategies are presented. Numerical results emphasize the gain of efficiency of the present simulation schemes with respect to standard DSMC methods.

This program is to develop an analytic method for reducing SUMS data for the determination of the undisturbed atmosphere conditions ahead of the shuttle along its descending trajectory. It is divided into an internal flow problem, an external flow problem and their matching conditions. Since the existing method of Direct Simulation Monte Carlo (DSMC) failed completely for the internal flow problem, the emphasis is on the internal flow of a highly non-equilibrium, rarefied air through a short tube of a diameter much less than the gaseous mean free path. A two fluid model analysis of this internal flow problem has been developed and studied with typical results illustrated. A computer program for such an analysis and a technical paper published in Lecture Notes in Physics No. 323 (1989) are included as Appendices 3 and 4. A proposal for in situ determination of the surface accommodation coefficients sigma sub t and sigma e is included in Appendix 5 because of their importance in quantitative data reduction. A two fluid formulation for the external flow problem is included as Appendix 6 and a review article for AIAA on Hypersonic propulsion, much dependent on ambient atmospheric density, is also included as Appendix 7.

This program is to develop an analytic method for reducing SUMS data for the determination of the undisturbed atmosphere conditions ahead of the shuttle along its descending trajectory. It is divided into an internal flow problem, an external flow problem and their matching conditions. Since the existing method of Direct Simulation Monte Carlo (DSMC) failed completely for the internal flow problem, the emphasis is on the internal flow of a highly non-equilibrium, rarefied air through a short tube of a diameter much less than the gaseous mean free path. A two fluid model analysis of this internal flow problem has been developed and studied with typical results illustrated. A computer program for such an analysis and a technical paper published in Lecture Notes in Physics No. 323 (1989) are included as Appendices 3 and 4. A proposal for in situ determination of the surface accommodation coefficients sigma sub t and sigma e is included in Appendix 5 because of their importance in quantitative data reduction. A two fluid formulation for the external flow problem is included as Appendix 6 and a review article for AIAA on Hypersonic propulsion, much dependent on ambient atmospheric density, is also included as Appendix 7.

This program is to develop an analytic method for reducing SUMS data for the determination of the undisturbed atmosphere conditions ahead of the shuttle along its descending trajectory. It is divided into an internal flow problem, an external flow problem and their matching conditions. Since the existing method of Direct Simulation Monte Carlo (DSMC) failed completely for the internal flow problem, the emphasis is on the internal flow of a highly non-equilibrium, rarefied air through a short tube of a diameter much less than the gaseous mean free path. A two fluid model analysis of this internal flow problem has been developed and studied with typical results illustrated. A computer program for such an analysis and a technical paper published in Lecture Notes in Physics No. 323 (1989) are included as Appendices 3 and 4. A proposal for in situ determination of the surface accommodation coefficients sigma sub t and sigma e is included in Appendix 5 because of their importance in quantitative data reduction. A two fluid formulation for the external flow problem is included as Appendix 6 and a review article for AIAA on Hypersonic propulsion, much dependent on ambient atmospheric density, is also included as Appendix 7.

The system of hydrodynamic-type equations is derived from Alexeev's generalized Boltzmann kinetic equation by two-side distribution function for a stratified gas in gravity field. It is applied to a problem of ultrasound propagation and attenuation. The linearized version of the obtained system is studied and compared with the Navier-Stokes one at arbitrary Knudsen numbers. The problem of a generation by a moving plane in a rarefied gas is explored and used as a test while compared with experiment. It is good agreement between predicted propagation speed, attenuation factor and experimental results for a wide range of Knudsen numbers.

A method for the design of a high vacuum enclosure was developed. The method utilizes design procedures recommended by the ASME Boiler and Pressure Vessel Code where directly applicable. Certain components, which are not adequately covered by the code, are designed by elementary stress analysis. The design method was developed and applied to a specific design, a rarefied gas dynamics and heat transfer chamber.

Research activities in the field of rarefied gasdynamics during the period September 1960 to August 1962 are reported in summary. Most of these constitute continuation of work reported previously, particularly in the experimental studies of rarefied gasdynamics and the attendant development of equipment experimental tools. New activities have been mainly in the general area of plasmadynamics which is distinguished from magnetohydrodynamics in that the gas in question is only partially ionized and the electrical conductivity is far from approaching infinity. This represents a direction towards treating realistic problems, some of which are of engineering interest, such as the re-entry radio communication problem.

The report contains reviews prepared during the meeting of papers in the following areas: transition flow, experimental techniques and apparatus, surface interactions, kinetic theory, molecular beams, internal flow, and rarefied plasmas and shock structure.

The report contains reviews prepared during the meeting of papers in the following areas: transition flow, experimental techniques and apparatus, surface interactions, kinetic theory, molecular beams, internal flow, and rarefied plasmas and shock structure.

No abstract available

This book contains the abstracts of papers presented at the All-Russia Seminar Kinetic Theory and Rarefied Gas Dynamics 2-6 December, 2002. The results of theoretical and experimental investigations on the following topics are given in the papers: kinetic theory, non-equilibrium statistical mechanics, irreversibility and dynamic chaos, transport processes and relaxation phenomena in gases and liquids, gas-surface interaction, methods of solving the kinetic equations, gas and liquid simulation methods, rarefied gas dynamics, physics and dynamics of clusters and aerosols. The issue is meant for specialists in the field of kinetic theory, continuum mechanics, non-equilibrium processes physics, as well as for students and post-graduate students of the corresponding specialties.

The objectives are to provide a parametric description of the electrostatic interaction of a mesosonic, collisionless plasma with conducting bodies on the order of 1 to 10 Debye lengths in size, and to extend this description to the satellite-ionospheric interaction, where possible. Experimental findings include: the wake of the geometrically complex body appears to be a linear superposition of the wakes of its simple geometric components; and vector ion flux measurements show converging ion streams at the wake axis and direct evidence of ion streams deflected from the wake axis by the positive space charge potential associated with the axial ion peak. The extension to the satellite-ionospheric interaction utilizes qualitative scaling and indicates that similar, but smaller amplitude, wake structures may be expected for small or highly charged bodies. However, for large bodies at small potentials, the structure may be diffused by the thermal ion motion and the dispersion resulting for space charge potentials.

International Symposium on Rarefied Gas Dynamics: Proceedings is an active publication covering gas dynamics. It was established in 1958 and was published irregularly by the University of Victoria.

In this paper we genealize the fast semi-Lagrangian scheme developed in [J. Comput. Phys., Vol. 255, 2013, pp 680-698] to the case of high order reconstructions of the distribution function. The original first order accurate semi-Lagrangian scheme is supplemented with polynomial reconstructions of the distribution function and of the collisional operator leading to an effective high order accurate numerical scheme for all regimes, from extremely rarefied gas to highly collisional siuation. The main idea relies on updating at each time step the extreme points of the distribution function for each velocity of the lattice instead of updating the solution in the cell centers, these extremes points being located at different positions for any fixed velocity of the lattice. The result is a class of scheme which permits to preserve the structure of the solution over very long times compared to existing schemes from the literature. We propose a proof of concept of this new approach along with numerical tests and comparisons with classical numerical methods.

The equations of fluid dynamics developed in paper I are applied to the study of the propagation of ultrasound waves. There is good agreement between the predicted propagation speed and experimental results for a wide range of Knudsen numbers.