Download or read book Microgravity Two phase Flow and Heat Transfer written by Kamiel S. Gabriel and published by Springer Science & Business Media. This book was released on 2007-05-10 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multiphase thermal systems have numerous applications in aerospace, heat-exchange, transport of contaminants in environmental systems, and energy transport and conversion systems. A reduced - or microgravity - environment provides an excellent tool for accurate study of the flow without the masking effects of gravity. This book presents for the first time a comprehensive coverage of all aspects of two-phase flow behaviour in the virtual absence of gravity.

Download or read book Design Manual for Microgravity Two Phase Flow and Heat Transfer written by Christopher J. Crowley and published by . This book was released on 1989 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report documents two-phase fluid flow and heat transfer methods for microgravity environments. The applications of the work are thermal management, propulsion, and fluid storage and transfer systems for spacecraft. In the near future, these systems will include two-phase, vapor-liquid flows. This Design Manual is intended for use by designers of these systems. Design methods are presented for predicting two-phase flow regimes and pressure drops in pipe flows from earth gravity to microgravity conditions. Forced convection boiling heat transfer methods for pipes with uniform heat flux are included. Also included are methods for analyzing high-vapor-shear condensation in pipes. The analysis methods are mechanistic; that is, based upon fundamental physical principles which should apply to heat transfer liquids with Pr approx = 1 and scale with pipe size and fluid properties. This Manual incorporates simplified methods (easy-to-use design charts), detailed descriptions of the analysis methods, comparisons with existing microgravity data, and recommended approaches to quantify the range of uncertainty in design calculations. Keywords: Fluid flow; Heat transfer; Space technology; Spacecraft components; Thermodynamics; Two phase flow. (jhd).

Download or read book Microgravity Two phase Flow and Heat Transfer written by A. A. M. Delil and published by . This book was released on 1999 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Two phase Flow Heat Transfer Under Microgravity Condition written by M. Parang and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Microgravity Liquid gas Two phase Flow written by Ramaswamy Balasubramaniam and published by . This book was released on 2019 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bubble Dynamics Two Phase Flow and Boiling Heat Transfer in Microgravity written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-23 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report contains two independent sections. Part one is titled Terrestrial and Microgravity Pool Boiling Heat Transfer and Critical heat flux phenomenon in an acoustic standing wave. Terrestrial and microgravity pool boiling heat transfer experiments were performed in the presence of a standing acoustic wave from a platinum wire resistance heater using degassed FC-72 Fluorinert liquid. The sound wave was created by driving a half wavelength resonator at a frequency of 10.15 kHz. Microgravity conditions were created using the 2.1 second drop tower on the campus of Washington State University. Burnout of the heater wire, often encountered with heat flux controlled systems, was avoided by using a constant temperature controller to regulate the heater wire temperature. The amplitude of the acoustic standing wave was increased from 28 kPa to over 70 kPa and these pressure measurements were made using a hydrophone fabricated with a small piezoelectric ceramic. Cavitation incurred during experiments at higher acoustic amplitudes contributed to the vapor bubble dynamics and heat transfer. The heater wire was positioned at three different locations within the acoustic field: the acoustic node, antinode, and halfway between these locations. Complete boiling curves are presented to show how the applied acoustic field enhanced boiling heat transfer and increased critical heat flux in microgravity and terrestrial environments. Video images provide information on the interaction between the vapor bubbles and the acoustic field. Part two is titled, Design and qualification of a microscale heater array for use in boiling heat transfer. This part is summarized herein. Boiling heat transfer is an efficient means of heat transfer because a large amount of heat can be removed from a surface using a relatively small temperature difference between the surface and the bulk liquid. However, the mechanisms that govern boiling heat transfer are not well understood. Measurements of wall te...

Download or read book Studies of Two Phase Flow Dynamics and Heat Transfer at Reduced Gravity Conditions written by and published by . This book was released on 1996 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Encyclopedia Of Two phase Heat Transfer And Flow Ii Special Topics And Applications A 4 volume Set written by John R Thome and published by World Scientific. This book was released on 2015-08-26 with total page 1321 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of the two-set series is to present a very detailed and up-to-date reference for researchers and practicing engineers in the fields of mechanical, refrigeration, chemical, nuclear and electronics engineering on the important topic of two-phase heat transfer and two-phase flow. The scope of the first set of 4 volumes presents the fundamentals of the two-phase flows and heat transfer mechanisms, and describes in detail the most important prediction methods, while the scope of the second set of 4 volumes presents numerous special topics and numerous applications, also including numerical simulation methods.Practicing engineers will find extensive coverage to applications involving: multi-microchannel evaporator cold plates for electronics cooling, boiling on enhanced tubes and tube bundles, flow pattern based methods for predicting boiling and condensation inside horizontal tubes, pressure drop methods for singularies (U-bends and contractions), boiling in multiport tubes, and boiling and condensation in plate heat exchangers. All of these chapters include the latest methods for predicting not only local heat transfer coefficients but also pressure drops.Professors and students will find this 'Encyclopedia of Two-Phase Heat Transfer and Flow' particularly exciting, as it contains authored books and thorough state-of-the-art reviews on many basic and special topics, such as numerical modeling of two-phase heat transfer and adiabatic bubbly and slug flows, the unified annular flow boiling model, flow pattern maps, condensation and boiling theories, new emerging topics, etc.

Download or read book Physics of Fluids in Microgravity written by Rodolfo Monti and published by CRC Press. This book was released on 2002-01-10 with total page 630 pages. Available in PDF, EPUB and Kindle. Book excerpt: In a microgravity experiment, the conditions prevalent in fluid phases can be substantially different from those on the ground and can be exploited to improve different processes. Fluid physics research in microgravity is important for the advancement of all microgravity scients: life, material, and engineering. Space flight provides a unique laboratory that allows scientists to improve their understanding of the behaviour of fluids in low gravity, allowing the investigation of phenomena and processes normally masked by the effects of gravity and thus difficult to study on Earth. Physics of Fluids in Microgravity provides a clear view of recent research and progress in the different fields of fluid research in space. The topics presented include bubles and drops dynamics, Maragoni flows, diffustion and thermodiffusion, solidfication,a nd crystal growth. The results obtained so far are, in some cases, to be confirmed by extensive research activities on the International Space station, where basic and applied microgravity experimentation will take place in the years to come.

Download or read book Cryogenic Two phase Flow and Phase change Heat Transfer in Microgravity written by Cheng-Feng Tai and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Cut-cell approach is applied to handle nonrectangular cells cut by the interfacesand boundaries in SIMCC. With the Cut-cell approach, the conservative properties can be maintained better near the interface. This research will focus on developing the numerical techniques to simulate the two-phase flow and phase change phenomena for one of the major flow patterns in film boiling, the inverted annular flow.

Download or read book Studies of Two Phase Flow Dynamics and Heat Transfer at Reduced Gravity Conditions written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-11 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ability to predict gas-liquid flow patterns is crucial to the design and operation of two-phase flow systems in the microgravity environment. Flow pattern maps have been developed in this study which show the occurrence of flow patterns as a function of gas and liquid superficial velocities as well as tube diameter, liquid viscosity and surface tension. The results have demonstrated that the location of the bubble-slug transition is affected by the tube diameter for air-water systems and by surface tension, suggesting that turbulence-induced bubble fluctuations and coalescence mechanisms play a role in this transition. The location of the slug-annular transition on the flow pattern maps is largely unaffected by tube diameter, liquid viscosity or surface tension in the ranges tested. Void fraction-based transition criteria were developed which separate the flow patterns on the flow pattern maps with reasonable accuracy. Weber number transition criteria also show promise but further work is needed to improve these models. For annular gas-liquid flows of air-water and air- 50 percent glycerine under reduced gravity conditions, the pressure gradient agrees fairly well with a version of the Lockhart-Martinelli correlation but the measured film thickness deviates from published correlations at lower Reynolds numbers. Nusselt numbers, based on a film thickness obtained from standard normal-gravity correlations, follow the relation, Nu = A Re(sup n) Pr(exp l/3), but more experimental data in a reduced gravity environment are needed to increase the confidence in the estimated constants, A and n. In the slug flow regime, experimental pressure gradient does not correlate well with either the Lockhart-Martinelli or a homogeneous formulation, but does correlate nicely with a formulation based on a two-phase Reynolds number. Comparison with ground-based correlations implies that the heat transfer coefficients are lower at reduced gravity than at normal gravity under the same ...

Download or read book Heat Transfer in Microgravity Systems written by and published by . This book was released on 1994 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Heat Transfer Co efficients During Two phase Gas Liquid Flow in a Circular Tube Under Microgravity Conditions written by Raymond W. Rite and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Second Microgravity Fluid Physics Conference written by and published by . This book was released on 1994 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thermohydraulic and Flow Regime Analysis for Condensing Two Phase Flow in a Microgravity Environment written by Doojeong Lee and published by . This book was released on 1987 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Microgravity Flow Regime Transition Modeling written by Adam Michael Shephard and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Flow regime transitions and the modeling thereof underlie the design of microgravity two-phase systems. Through the use of the zero-g laboratory, microgravity two-phase flows can be studied. Because microgravity two-phase flows exhibit essentially no accelerations (i.e. no buoyancy or gravitational forces), the effects of acceleration on two-phase flow can be decoupled from the effects of other fluid phenomenon. Two-phase systems on earth are understood mostly through empiricisms. Through microgravity two-phase research, a fundamental understanding of two-phase systems can be obtained and applied to both terrestrial systems in space applications. Physically based bubbly-bubbly/slug and bubbly/slug-slug flow regime transition models are introduced in this study. The physical nature of the models demonstrates a new understanding of the governing relationships between coalescence, turbulence, void fraction, boundary layer affects, and the inlet bubble size distribution. Significantly, the new models are dimensionless in addition to being physically derived. New and previous models are evaluated against zero-g data sets. Previous models are not accurate enough for design use. The new models proposed in this study are far more detailed than existing models and are within the precision necessary for most design purposes. Because of the limited data available, further experimental validation is necessary to formally vet the model. Zero-g data set qualification and flight experiment design have not been standardized and as a result, much of the data in the literature can be shown not to represent microgravity conditions. In this study, a set of zero-g quality criteria are developed and used to qualify the data sets available in the literature. The zero-g quality criteria include limitations on buoyancy forces relative to surface tension and inertial forces as well as requirements on acceleration monitoring and flow development length and time. The resulting evaluation of the data sets available in the literature unveils several experiment design shortfalls, which have resulted in data sets being misrepresented as zero-g data sets. The quality standards developed in this study should continue to be improved upon and used in the design of future zero-g fluid experiments. The use of one-g single-phase models in approximating zero-g two-phase experimental data was successfully performed in this study. Specifically the models for pressure drop, friction factor, wall shear, and velocity profile are demonstrated. It is recognized that the mixing apparatus will affect the flow regime transitions, specifically the distribution of bubble sizes that exit the mixing apparatus. Unfortunately, little-to-no information regarding the mixing apparatus used in past experiments can be found in the literature. This will be an area for further developmental research. In summary, the approach to understanding and modeling two-phase phenomenon demonstrated in this study provides tools to future researchers and engineers. Special attention to data qualification and experiment standardization provides a different prospective and interpretation of the currently available data. The physically based and dimensionless modeling demonstrated in this study can be extended to other studies in the field as well as providing a basis for the application of heat transfer modeling to microgravity two-phase systems, specifically boiling and condensation.

Download or read book Microgravity Fluid Physics and Heat Transfer written by V. K. Dhir and published by Begell House Publishers. This book was released on 2000 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: