Download or read book Experimental and Numerical Study of Nozzle Plume Impingement on Spacecraft Surfaces written by and published by . This book was released on 2005 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental and numerical effort was undertaken to assess the effects of a cold gas (To=300K) nozzle plume impinging on a simulated spacecraft surface. The nozzle flow impingement is investigated experimentally using a nano-Newton resolution force balance and numerically using the Direct Simulation Monte Carlo (DSMC) numerical technique. The Reynolds number range investigated in this study is from 0.5 to approximately 900 using helium and nitrogen propellants. The thrust produced by the nozzle was first assessed on a force balance to provide a baseline case. Subsequently, an aluminum plate was attached to the same force balance at various angles from 0 degrees (parallel to the plume flow) to 10 degrees. For low Reynolds number helium flow, a 16.5% decrease in thrust was measured for the plate at 0 degrees relative to the free plume expansion case. For low Reynolds number nitrogen flow, the difference was found to be 12%. The thrust degradation was found to decrease at higher Reynolds numbers and larger plate angles.
Download or read book Nozzle Plume Impingement on Spacecraft Surfaces Effects of Surface Roughness POSTPRINT written by and published by . This book was released on 2005 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental and numerical effort was undertaken to assess the effects of a cold gas (To=300K) nozzle plume impinging on a simulated spacecraft surface. The nozzle flow impingement is investigated experimentally using a nano-Newton resolution force balance and numerically using the Direct Simulation Monte Carlo (DSMC) numerical technique. The Reynolds number range investigated in this study is from 0.5 to approximately 900 using helium and nitrogen propellants. The thrust produced by the nozzle was first assessed on a force balance to provide a baseline case. Subsequently, an aluminum plate was attached to the same force balance at various angles from 0? (parallel to the plume flow) to 10?. For low Reynolds number helium flow, a 16.5% decrease in thrust was measured for the plate at 0? relative to the free plume expansion case. For low Reynolds number nitrogen flow, the difference was found to be 12%. The thrust degradation was found to decrease at higher Reynolds numbers and larger plate angles. The roughness of the simulated spacecraft surface will be a variable in the testing to be performed for this manuscript.
Download or read book Experimental and Numerical Study of Spacecraft Contamination Problems Associated With Gas and Gas Droplet Thruster Plume Flows written by and published by . This book was released on 2006 with total page 219 pages. Available in PDF, EPUB and Kindle. Book excerpt: The project consists of two large parts. The first part is the study of plume flows escaping into vacuum, and the second part deals with gasdroplet flows. These two parts are united by a common area of research, namely, contamination problems of space station surfaces due to thruster firing. The objective of the first part is accurate prediction of force and heat loads and contamination due to interaction of thruster plumes with the spacecraft surface. This requires a detailed knowledge of the plume structure. For this purpose, a software system SMILE (Statistical Modeling In Low-density Environment) is developed for modeling plume flows. This system is based on the Direct Simulation Monte Carlo (DSMC) method and incorporates economical numerical schemes of the DSMC method majorant frequency scheme, advanced models that describe energy transfer in the case of collisions of diatomic and polyatomic molecules, possibilities of parallelization, and models for chemically reacting flows of polyatomic gases. An important aspect associated with this activity is the use of advanced object-oriented approaches for the development of the SMILE system. The objective of the second part is an experimental and numerical study of a two-phase gas-droplet flow arising in the case of simultaneous exhaustion of liquid and gas into vacuum. This problem is closely related to the processes of backflow contamination of spacecraft surfaces by thruster plumes with a fuel film used for cooling the inner surface of the nozzle. The main attention is paid to studying the behavior of droplets into which the liquid is decomposed at the initial stage of droplet motion and to the interaction of droplets with a freely expanding gas plume.
Download or read book Rarefied Gas Dynamics written by M. Capitelli and published by American Institute of Physics. This book was released on 2005-06-21 with total page 1386 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book contains papers presented at the 24th International Symposium on Rarefied Gas Dynamics, a conference that is recognized as the principal forum for the presentation of recent advances in the field of rarefied gas dynamics. The topics include fundamental aspects of Boltzmann and related equations, transport theory, Monte Carlo methods, kinetic theory, gas phase molecular collision dynamics, gas surface interaction, state to state kinetics, rarefied plasmas, and non-equilibrium plasma kinetics. Applications in the fields of internal flows, vacuum systems, rarefied jets, plumes, molecular beams, scamjets and hypersonics, microflows, granular gases, electrical thrusters are discussed. Researchers in the fields of mathematics, physics, chemistry and engineering can strongly benefit from the interdisciplinary nature of the book.
Download or read book Automatic Control in Aerospace 1992 written by D.B. DeBra and published by Elsevier. This book was released on 2017-01-11 with total page 573 pages. Available in PDF, EPUB and Kindle. Book excerpt: Space vehicles have become increasingly complex in recent years, and the number of missions has multiplied as a result of extending frontiers in the exploration of our planetary system and the universe beyond. The advancement of automatic control in aerospace reflects these developments. Key areas covered in these proceedings include: the size and complexity of spacecrafts and the increasingly stringent performance requirements to be fulfilled in a harsh and unpredictable environment; the merger of space vehicles and airplanes into space planes to launch and retrieve payloads by reusable winged vehicles; and the demand to increase space automation and autonomy to reduce human involvement as much as possible in manned, man-tended and unmanned missions. This volume covers not only the newly evolving key technologies but also the classical issues of guidance, navigation and control.
Download or read book Numerical Simulation of Rarefied Nozzle Plume Impingements written by and published by . This book was released on 2000 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper describes numerical simulation of rarefied nozzle plume impingements. Two different reservoir pressures 400 kPa and 4 kPa are considered, In the case of 400 kPa, the simulation of the nozzle flow was conducted by using the Navier-Stokes equation and then the analysis of the plume flow was carried out by the DSMC method employing the nozzle exit conditions obtained by Navier-Stokes equation. On the other hand., for 4 kPa both the nozzle flow and the plume impingement have been calculated using the DSMC method. Concerning the angle between the nozzle axis and the flat plate, three kinds of angle are selected, that is 90 degrees, 45 degrees and 0 degrees. In addition, we considered the case where there exists a flat plate behind the nozzle. Simulated results have been compared with the existing experiments for the pressure and shear stress distributions on the flat plate. A good agreement between the DSMC results and the experiments are shown. In the case of the oblique and parallel impingements, the location of the impingement pressure peak and the stagnation point shifted upstream with increasing rarefaction.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 38th AIAA Thermophysics Conference 05 5062 05 5392 written by and published by . This book was released on 2005 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparison of Hall Thruster Plume Expansion Model with Experimental Data Preprint written by and published by . This book was released on 2006 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical modeling of the expansion of electric thruster plumes provides direct means for predicting spacecraft surface contamination and erosion due to plume ions. A software package named COLISEUM that is capable of self-consistently modeling plasma propagation and interactions with arbitrary 3-D surfaces is being developed by a national team of researchers. Despite much research and development in modeling plume expansion, it is necessary to continuously validate these codes using laboratory based experimental data. It is well-established that vacuum chamber facilities affect the plume of these devices. Thus, the models must not only describe the plume expansion, but also effects of the vacuum chamber. COLISEUM has been designed to simulate both vacuum chamber configurations and spacecraft geometries. This work provides source derivation from laser induced florescence (LIF) data. Included is a study that compares results from a hybrid particle-in-cell model (AQUILA) with Monte Carlo collisions to data obtained from the plume of Busek 600W Hall thruster (BHT-HD-600). This data includes current density, velocity distribution, and energy data.
Download or read book Probabilistic Design of a Rocket Nozzle written by and published by . This book was released on 2008 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Automatic Control in Aerospace written by and published by . This book was released on 1993 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Study of Rarefied Hypersonic Flow Interacting with a Continuum Jet written by Christopher E. Glass and published by . This book was released on 2000 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: An uncoupled CFD-DSMC technique is developed and applied to provide solutions for continuum jets interacting with rarefield external flows. The technique is based on a correlation of the appropriate Bird breakdown parameter for a transitional-rarefield condition that defines a surface within which the continuum solution is unaffected by the external flow-jet interaction. The method is applied to two problems to assess and demonstrate its validity: one of a jet interaction in the transitional-rarefied flow regime and the other in the moderately rarefield regime. Results show that the appropriate Bird breakdown surface for uncoupling the continuum and non-continuum solutions is a function of a non-dimensional parameter relating the momentum flux and collisionality between the two interacting flows.
Download or read book An Investigation of Highly Underexpanded Exhaust Plumes Impinging Upon a Perpendicular Flat Surface written by Allen R. Vick and published by . This book was released on 1966 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 40th AIAA ASME SAE ASEE Joint Propulsion Conference Exhibit July 11 14 2004 Fort Lauderdale FL written by and published by . This book was released on 2004 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Combined CFD DSMC Method for Numerical Simulation of Nozzle Plume Flows written by Jyothish D. George and published by . This book was released on 2000 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fluid Mechanics and Fluid Power Volume 3 written by Krishna Mohan Singh and published by Springer Nature. This book was released on 2024-01-16 with total page 726 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprises select peer-reviewed proceedings of the 9th International and 49th National Conference on Fluid Mechanics and Fluid Power (FMFP 2022). This book brings together scientific ideas and engineering solutions put forth by researchers and practitioners from academia and industry in the important and ubiquitous field of fluid mechanics. The contents of this book focus on fundamental issues and perspective in fluid mechanics, measurement techniques in fluid mechanics, computational fluid and gas dynamics, instability, transition and turbulence, fluid-structure interaction, multiphase flows, microfluidics, bio-inspired fluid mechanics, aerodynamics, turbomachinery, propulsion and power and other miscellaneous topics in the broad domain of fluid mechanics. This book is a useful reference to researchers and professionals working in the broad field of mechanics.
Download or read book Applied mechanics reviews written by and published by . This book was released on 1948 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
