Download or read book Gas Replenishment Techniques for Use in High altitude Long duration Scientific Balloon Flights written by Andrew S. Carten (Jr.) and published by . This book was released on 1979 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report covers the theoretical advantages and practical ramifications of a proposed new technique for compensating for the daily loss of lift (gamma) experienced by long-duration high-altitude scientific balloon flights. This technique, 'Gas Replenishment', would transfer stored helium from an onboard dewar to the balloon, to replace gas lost due to temperature excursions. It would be a direct substitute for systems presently in use which drop ballast, that is, reduce system gross weight, to compensate for loss of lift. (With gas replenishment, lift is restored directly, with only a small change in system gross weight. A short summary of zero-pressure balloon flight theory is given at the start, to lead into the explanation of conventional ballast practices and computations. The ballast equations are then modified to apply to the gas replenishment technique. Calculations for typical constant-gamma flights are summarized for each method of loss compensation and the clear superiority of gas replenishment is demonstrated in the areas of gross system weight of launch, usable payload weight and anticipated flight duration. Basic equations are then developed for a more complicated model of the gas replenishment system in which the value of gamma varies from day to day. Computations using these formulas are summarized in tabular form. The final section of the report is given over to the design problems associated with the type of dewar and heat exchange equipment needed to implement the gas replenishment concept. (Author).
Download or read book Gas Replenishment Techniques for Use in High altitude Long duration Scientific Balloon Flights written by Andrew S. Carten and published by . This book was released on 1979 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report covers the theoretical advantages and practical ramifications of a proposed new technique for compensating for the daily loss of lift (gamma) experienced by long-duration high-altitude scientific balloon flights. This technique, 'Gas Replenishment', would transfer stored helium from an onboard dewar to the balloon, to replace gas lost due to temperature excursions. It would be a direct substitute for systems presently in use which drop ballast, that is, reduce system gross weight, to compensate for loss of lift. (With gas replenishment, lift is restored directly, with only a small change in system gross weight. A short summary of zero-pressure balloon flight theory is given at the start, to lead into the explanation of conventional ballast practices and computations. The ballast equations are then modified to apply to the gas replenishment technique. Calculations for typical constant-gamma flights are summarized for each method of loss compensation and the clear superiority of gas replenishment is demonstrated in the areas of gross system weight of launch, usable payload weight and anticipated flight duration. Basic equations are then developed for a more complicated model of the gas replenishment system in which the value of gamma varies from day to day. Computations using these formulas are summarized in tabular form. The final section of the report is given over to the design problems associated with the type of dewar and heat exchange equipment needed to implement the gas replenishment concept. (Author)
Download or read book Gas Replenishment Techniques for Use in High altitude Long duration Scientific Balloon Flights written by Andrew S. Carten (Jr.) and published by . This book was released on 1979 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report covers the theoretical advantages and practical ramifications of a proposed new technique for compensating for the daily loss of lift (gamma) experienced by long-duration high-altitude scientific balloon flights. This technique, 'Gas Replenishment', would transfer stored helium from an onboard dewar to the balloon, to replace gas lost due to temperature excursions. It would be a direct substitute for systems presently in use which drop ballast, that is, reduce system gross weight, to compensate for loss of lift. (With gas replenishment, lift is restored directly, with only a small change in system gross weight. A short summary of zero-pressure balloon flight theory is given at the start, to lead into the explanation of conventional ballast practices and computations. The ballast equations are then modified to apply to the gas replenishment technique. Calculations for typical constant-gamma flights are summarized for each method of loss compensation and the clear superiority of gas replenishment is demonstrated in the areas of gross system weight of launch, usable payload weight and anticipated flight duration. Basic equations are then developed for a more complicated model of the gas replenishment system in which the value of gamma varies from day to day. Computations using these formulas are summarized in tabular form. The final section of the report is given over to the design problems associated with the type of dewar and heat exchange equipment needed to implement the gas replenishment concept. (Author).
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Instrumentation Papers written by and published by . This book was released on 1979 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific Ballooning III written by W. Riedler and published by . This book was released on 1983 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Annual Department of Defense Bibliography of Logistics Studies and Related Documents written by United States. Defense Logistics Studies Information Exchange and published by . This book was released on 1981 with total page 1052 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fundamental Aspects of Materials Science in Space written by Y. Malméjac and published by . This book was released on 1983 with total page 810 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Problem Instantaneously Effecting Controlled Balloon system Descent from High Altitude written by James F. Dwyer and published by . This book was released on 1980 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: The need for a technique of instantaneously effect controlled balloon-system descent from high altitude prompted the development efforts reported herein. The background, the approach, test flight data, and the technical problems that frustrated the successful development of the desired technique are included. A simplified model of the shape of a partially full balloon is presented (a model that should also approximate the dimensions of subpressure shapes). Some heretofore unpublished information on apex valve characteristics and subpressure effects are included together with recommendations for any future work of this problem. Significant supplementary findings and historical perspectives are noted. (Author).
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1980 with total page 1414 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA SP written by and published by . This book was released on 1992 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technical Abstract Bulletin written by and published by . This book was released on with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1996 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeronautical Engineering written by and published by . This book was released on 1992 with total page 828 pages. Available in PDF, EPUB and Kindle. Book excerpt: A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).
Download or read book R D Abstracts written by Technology Reports Centre (Great Britain) and published by . This book was released on 1980 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Temperature Control Technique for Long Duration Balloons written by Winzen International, Inc and published by . This book was released on 1993 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scientific balloon flight can be extended for indefinite periods by covering the radiative balance on the balloon structure. This is achieved by active control of an internal element specifically chosen for its absorptive and emissive properties. The element, called the "radiative Curtain", is opened, closed and oriented perpendicular ro the sun to control balloon gas temperature which in turn controls the expansion, contraction and venting of the gas to enable extended flights. The technique was shown to be feasible during phase I SBIR study, Phase II SBIR objectives are to select the optimum size, thickness, and material to the curtain; design, analyze, and test curtain deployment system; improve accuracy of gas temperature measurements and modify a zero pressure balloon to incorporate the curtain system. Winzen will design and construct test articles, plan and execute a comprehensive flight test program, and deliver final test article to National Scientific Balloon Facility. Expected results will confirm that a radiative curtain will control lifting gas temperature to a degree that will significantly reduce or eliminate diurnal temperature changes, thus reduce or eliminate need for ballast, resulting in significantly longer mission duration. Additionally, the Acoustic Thermometer will be developed as a means for accurate and direct measurement of balloon gas temperature.
Download or read book Aeronautical Engineering 1983 Cumulative Index written by and published by . This book was released on 1984 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:
