Download or read book Experimental and Theoretical Investigation of Operational and Survivability Issues in Thermal Radiators for Thermionic Space Nuclear Power Systems written by and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental and Theoretical Investigation of Operational and Survivability Issues in Thermal Radiators for Thermionic Space Nuclear Power Systems Final Report written by and published by . This book was released on 1994 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat pipes are a promising candidate for spacecraft radiators. This report describes a program designed to investigate the mass migration phenomenon in heat pipes. The program involved experiments to observe and measure the mass migration rates in both high and low operating temperature heat pipes. The low-temperature experiments were intended to simulate the operation of high-temperature, liquid metal heat pipes. Octadecane was the selected low-temperature working fluid. It is a paraffin and exhibits some of the characteristics of liquid metal working fluids. Sodium was the working fluid used in the high temperature experiment. A one-dimensional compressible flow model was developed for describing the hydrodynamics of rarefied vapor flow in heat pipe condensers. This model was compared with experimental data for the low-temperature octadecane heat pipes and the high-temperature sodium heat pipe. The model was found to satisfactorily predict the temperature profiles and location of freeze-fronts for the low-temperature heat pipes. Mass migration rate predictions using the model were satisfactory for the low-temperature heat pipes as well. However, the mass migration prediction for the high-temperature, sodium heat pipe was not in agreement with experimental data. An analytical model which accounts for property variations in the radial as well as longitudinal directions is recommended. A one-dimensional model was unsatisfactory for predicting mass migration rates in liquid metal heat pipes.

Download or read book Energy Research Abstracts written by and published by . This book was released on 1995 with total page 782 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Review of Advanced Radiator Technologies for Spacecraft Power Systems and Space Thermal Control written by Albert J. Juhasz and published by . This book was released on 1994 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index written by and published by . This book was released on 1994 with total page 1690 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of Radiators for Space Nuclear Power Systems written by Roy W. Blanton and published by . This book was released on 1964 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Simulations of a Rotating Bubble Membrane Radiator for Space Nuclear Power Systems written by Homan Mohammed-Zahid Al-Baroudi and published by . This book was released on 1993 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: A rotating, flat plate condensation experiment has been developed to investigate the heat of the Rotating Bubble Membrane Radiator (RBMR). The RBMR is a proposed heat rejection system for space applications which uses working fluid condensation on the inside surface of a rotating sphere to reject heat to space. The flat plate condensation heat transfer experiment simulates the microgravity environment of space by orienting the axis of rotation parallel to the gravitational vector and normal to the surface of the plate. The condensing surface is cooled to simulate the rejection of heat to cold surface. The working fluid is a super heated steam. The results obtained include relationships between the overall heat transfer coefficient as a function of the temperature difference between the working fluid and a cold environment, both placed in dimensionless groups, and plate angular rotational speeds. This empirical relationship is useful for choosing the optimum rotational speed for the flat plate radiator given a desired heat rejection load. A RBMR prototype, using full sphere shell, was designed and built completely in this research efforts and ready to be tested in future planned experiments in microgravity environment. This RBMR is the first one ever built to investigate the RBMR concepts experimentally. This study also provides the basis for designing new heat rejection systems utilizing centrifugal forces and condensation phenomena in both space and ground applications.

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1994 with total page 848 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Space Station Systems written by and published by . This book was released on 1986 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiators in Hydronic Heating Installations written by Damian Piotr Muniak and published by Springer. This book was released on 2017-03-21 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses key design and computational issues related to radiators in hydronic heating installations. A historical outline is included to highlight the evolution of radiators and heating technologies. Further, the book includes a chapter on thermal comfort, which is the decisive factor in selecting the ideal heating system and radiator type. The majority of the book is devoted to an extensive discussion of the types and kinds of radiators currently in use, and to identifying the reasons for the remarkable diversity of design solutions. The differences between the solutions are also addressed, both in terms of the effects of operation and of the thermal comfort that needs to be ensured. The book then compares the advantages and disadvantages of each solution, as well as its potential applications. A detailed discussion, supported by an extensive theoretical and mathematical analysis, is presented of the computational relations that are used in selecting the radiator type. The dynamics of radiator heat output regulation are also covered, with particular emphasis on underfloor-surface radiators, for which this aspect is particularly important. The book closes with a chapter presenting computational examples. It includes numerous examples of calculations for all essential thermal parameters of radiator operation in heating installations.

Download or read book Design considerations for lightweight space radiators based on fabrication and test experience with a carboncarbon composite prototype heat pipe written by and published by DIANE Publishing. This book was released on with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nuclear Thermionic Space Power System Concept Employing Heat Pipes written by Colin A. Heath and published by . This book was released on 1968 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Review of Advanced Radiator Technologies for Spacecraft Power Systems and Space Thermal Control written by National Aeronautics and Space Adm Nasa and published by . This book was released on 2018-10-19 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: A two-part overview of progress in space radiator technologies is presented. The first part reviews and compares the innovative heat-rejection system concepts proposed during the past decade, some of which have been developed to the breadboard demonstration stage. Included are space-constructable radiators with heat pipes, variable-surface-area radiators, rotating solid radiators, moving-belt radiators, rotating film radiators, liquid droplet radiators, Curie point radiators, and rotating bubble-membrane radiators. The second part summarizes a multielement project including focused hardware development under the Civil Space Technology Initiative (CSTI) High Capacity Power program carried out by the NASA Lewis Research Center and its contractors to develop lightweight space radiators in support of Space Exploration Initiative (SEI) power systems technology. Juhasz, Albert J. and Peterson, George P. Glenn Research Center RTOP 583-02-21...

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1985 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Space Radiator Study written by R. J. Denington and published by . This book was released on 1963 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Design techniques are presented for condenser radiators for condensing mercury, sodium, potassium, and rubidium vapors for Rankine cycle space power plants. Included in the design techniques are radiation heat transfer, fluid mechanics, meteoroid protection and materials considerations, with the fluid mechanics stability aspects emphasized. Parametric data for large alkali metal condenser radiators relating geometry to weight and area are presented. Tests were conducted with water, sodium, potassium, and rubidium to investigate flow regime and stability in vertical up flow condensing. A correlation is presented for predicting the transition from a stable annular film flow to a slugging regime. Techniques for estimating pressure drop and inventory are provided. Condensing heat transfer coefficients for potassium and rubidium are measured and found to vary from 200 to 4000 Btu/hr sq. ft. F at relatively low velocities and pressures. This report summarizes the recommended design procedures, parametric data and the experimental details.

Download or read book Weight Study of Partially Segmented Direct condensing Radiators for Large Space Power Systems written by Roy L. Johnsen and published by . This book was released on 1966 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analytical investigation has been performed to provide an insight into the weight increase of a direct-condensing radiator for a potassium Rankine cycle space power system as the system size was increased from 1 to 10 megawatts electric while holding constant the component efficiencies and all cycle temperatures and pressures. The largest single contributor to the radiator weight is the armor necessary to protect fluid passages from meteoroid puncture. The two most important factors affecting armor thickness are the meteoroid population estimate and the radiator design survival probability. Design survival probabilities of 0. 9, 0. 95, and 0. 99 were used with a high meteoroid population estimate, Whipple's (1961), and a low estimate, Watson's (1956), for 1, 10, 20, and 100 radiator segments. The radiator weight is sharply influenced by the meteoroid flux estimate and the design survival probability. For the unsegmented case, using Watson's (1956) flux estimate, the radiator weight ranged from 1. 5 to 3 pounds per kilowatt electric for the 1-to 10-megawatt power range for a 0. 9 radiator design survival probability, and 2. 5 to 6 pounds per kilowatt for a 0. 99 design survival probability. When Whipple's (1961) flux estimate was used, the radiator weight ranged from 7 to 17 pounds per kilowatt for a 0. 9 design survival probability and from 16 to 42 pounds per kilowatt for a 0. 99 design survival probability. Segmentation of the radiator provided significant weight savings over the unsegmented radiator, especially when high survival probabilities were demanded. Generally the weight advantages of segmentation increased with increases in system power level, design survival probability, number of segments, and severity of the meteoroid flux estimate.

Download or read book Analysis of Radiators for Space Nuclear Power Systems written by Roy W BLANTON (Jr) and published by . This book was released on 1964 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: A theoretical analysis is presented for designing heat radiators for space nuclear power systems. The analysis is for two configurations: conical, single-surface radiators and flat, tapered plate radiators. Both condensing and noncondensing fluid conditions are considered. A FORTRAN IV program is included. (Author).