Download or read book Field Tests of a Surface Ice Accretion Measurement System written by Paul Tattelman and published by . This book was released on 1980 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rosemont ice detectors were installed at four New England locations to collect information on their response to icing near the earth's surface. Data were collected for 11 icing events during the 1979-80 winter season. These included, for each icing event, the recorded output o the ice detectors, the mass, thickness and physical properties o the ice on a control cylinder, and meteorological conditions pertinent to the field tests. The data were analyzed to determine how accurately ice amounts on the cylinder could be estimated from the output of the ice detectors. Results indicate that the detector would be excellent for objectively estimating icing amounts on a cylinder for in-cloud icing on mountaintops. A slight modification and further testing is necessary to best use the instrument to estimate icing amounts from freezing rain or drizzle. A method for making standardized observations of the mass and thickness of ice on cylinders with varying diameters is also presented. (Author).
Download or read book Field Tests of a Surface Ice Accretion Measurement System written by Paul Tattelman and published by . This book was released on 1980 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rosemont ice detectors were installed at four New England locations to collect information on their response to icing near the earth's surface. Data were collected for 11 icing events during the 1979-80 winter season. These included, for each icing event, the recorded output o the ice detectors, the mass, thickness and physical properties o the ice on a control cylinder, and meteorological conditions pertinent to the field tests. The data were analyzed to determine how accurately ice amounts on the cylinder could be estimated from the output of the ice detectors. Results indicate that the detector would be excellent for objectively estimating icing amounts on a cylinder for in-cloud icing on mountaintops. A slight modification and further testing is necessary to best use the instrument to estimate icing amounts from freezing rain or drizzle. A method for making standardized observations of the mass and thickness of ice on cylinders with varying diameters is also presented. (Author)
Download or read book Climatic Chamber Tests of a Surface Ice Accretion Measurement System written by Paul Tattelman and published by . This book was released on 1979 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Climatic chamber tests of an off-the-shelf ice detection system manufactured by Rosemount Engineering Company were conducted to evaluate its capability to determine ice amounts measured on cylinders. One-hour tests were run for a variety of windspeeds, temperatures, and icing conditions. Some longer duration tests, up to 17 hours, were also performed. Analysis of the data indicates that the Rosemount system is highly correlated with the mass of ice measured on the cylinders when the data are divided into freezing rain and rime icing events. The Rosemount system is also highly correlated with ice thickness, but without the pronounced dependence upon the type of icing. In the light of positive test results, a method is proposed for utilizing the Rosemount system for observing ice accretion at the earth's surface. (Author).
Download or read book Air Force Surveys in Geophysics written by and published by . This book was released on 1980 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1982 with total page 1284 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development and Test of a Microwave Ice Accretion Measurement Instrument MIAMI written by Bertram Magenheim and published by . This book was released on 1982 with total page 92 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 1980 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Special Report written by and published by . This book was released on 1983 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography on Snow Ice and Frozen Ground with Abstracts written by and published by . This book was released on 1985 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wind Energy Systems written by John Dalsgaard Sørensen and published by Elsevier. This book was released on 2010-12-20 with total page 621 pages. Available in PDF, EPUB and Kindle. Book excerpt: Large-scale wind power generation is one of the fastest developing sources of renewable energy and already makes a substantial contribution to power grids in many countries worldwide. With technology maturing, the challenge is now to increase penetration, and optimise the design, construction and performance of wind energy systems. Fundamental issues of safety and reliability are paramount in this drive to increase capacity and efficiency.Wind energy systems: Optimising design and construction for safe and reliable operation provides a comprehensive review of the latest developments in the design, construction and operation of large-scale wind energy systems, including in offshore and other problematic environments.Part one provides detailed coverage of wind resource assessment and siting methods relevant to wind turbine and wind farm planning, as well as aeroelastics, aerodynamics, and fatigue loading that affect the safety and reliability of wind energy systems. This coverage is extended in part two, where the design and development of individual components is considered in depth, from wind turbine rotors to drive train and control systems, and on to tower design and construction. Part three explores operation and maintenance issues, such as reliability and maintainability strategies and condition monitoring systems, before discussing performance assessment and optimisation routes for wind energy systems in low wind speed environments and cold climates. Part four reviews offshore wind energy systems development, from the impact of environmental loads such as wind, waves and ice, to site specific construction and integrated wind farm planning, and of course the critical issues and strategies for offshore operation and maintenance.With its distinguished editors and international teams of contributors, Wind energy systems is a standard reference for wind power engineers, technicians and manufacturers, as well as researchers and academics involved in this expanding field. Reviews the latest developments in the design, construction and operation of large-scale wind energy systems Offers detailed coverage of wind resource assessment and siting methods relevant to wind turbine and wind farm planning Explores operation and maintenance issues, such as reliability and maintainability strategies and condition monitoring systems
Download or read book Government Reports Annual Index written by and published by . This book was released on 1981 with total page 942 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Water Vapor Precipitation Clouds and Fog written by D. D. Grantham and published by . This book was released on 1983 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Contamination Mitigating Polymeric Coatings for Extreme Environments written by Christopher J. Wohl and published by Springer Nature. This book was released on 2020-05-15 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume provides perspectives on the approaches, mechanisms, test methods, durability considerations, and environmental concerns for contamination mitigating coatings and polymers with emphasis on their use in more extreme aerospace and marine terrestrial environments. Parts of the Volume are devoted to application of biomimetics to contamination mitigation polymeric coatings, low ice adhesion surfaces, insect residue adhesion resistance coatings, and marine biofouling mitigation materials. By juxtaposing ice insect, and marine mitigation approaches, researchers and users may more easily identify threads of similarity that will assist in future developments and potential applications in these areas. The volume is of interest to chemists and material scientists in providing awareness of both the need for efficacy in mitigating contamination and for appropriate coating durability; to physicists in providing better understanding of the interaction between the contaminant, the coated surface, and the surrounding environment; and to engineers in describing the need for better scale-up tests between laboratory and field environments.
Download or read book Experimental Impact Dynamics Testing of a Glaciated Water Drop and Quantification of Partial Melting with Varying Residence Time written by Sihong Yan and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: High altitude ice crystals have been recently discovered to be the cause of engine and heated probe icing over high humidity tropical regions. Ice accretion related to partially melted ice crystals was first discovered in 2006 and it is a threat to aviation safety. It is known that ice crystals without any water content do not accrete to surfaces. The classical frame icing theory involving super-cooled water droplets cannot explain the cause of icing inside turbofan engines flying at altitudes where there is no water content, since only fully glaciated ice crystal clouds exist. To understand the icing conditions and physical mechanism of engine icing, research projects like the High Altitude Ice Crystal (HAIC) international project are been conducted, and test facilities, like the National Research Council icing wind tunnel or the NASA Propulsion System Laboratory tunnel, have been constructed. The correlation between engine icing events and mixed-phase icing clouds that partially melt when ingested in an engine has been confirmed in these facilities. Despite the availability of facilities to reproduce the ice accretion events inside engines, fundamental testing of individual partially melted water droplets is not available and the validation of tools to predict partial melting of crystals is not possible. The study of physical processes involved in the partial melting of a single ice crystal can be divided into two parts. The first part is the impact dynamics of the single droplet, and the second part is the melting process of the frozen droplet. Attempts to characterize these two phenomena were conducted at the Adverse Environmental Rotor Test Stand Facility at Penn State. To quantify impact dynamics of ice crystals, high-speed video of single frozen water droplets impacting a surface was acquired. The frozen particles had a diameter ranging from 0.4 mm to 0.9 mm and impacted at velocities varying from 90 m/sec to 309 m/sec. The technique used to freeze the droplets and launch the particles against a surface is described. High-speed video was used to quantify the ice accretion area to the surface for varying impact angles (30, 45, 60), and impacting velocities. An oxygen /acetylene cross-flow flame was used to partially melt the traveling frozen particles and it is also discussed. A linear relationship between impact angle and ice accretion is identified for fully frozen particles. The slope of the relationship is affected by impact speed. Higher impact angles closer to perpendicularity between the surface and the particle trajectory, e.g. 60, exhibited small differences in ice accretion with varying velocities. Increasing velocity from 161 m/sec to 259 m/sec nearly doubled the ice accretion area at a shallower impact angle of 30. The increase accretion area highlights the importance of impact angle and velocity on the accretion process of partially melted ice crystals. It was experimentally observed that partial melting was not a pre-requisite for accretion at the tested velocities when impact angles of 45 and 30 were used. The ice accretion due to impact was observed under five surface temperatures, -20C, -15C, -10C, 0C and 10C. The influence of the surface temperature was qualitatively observed at an impact angle of 30. The temperature varied from -15C to 10C, and a maximum area of ice accretion was observed at surface temperatures surrounding the freezing point of water. A second emphasis of the work was to correlate residence time requirements for the melting of frozen drops. To characterize the melting process of fully glaciated droplets, a luminescent technique was developed to measure the percentage of melting experimentally. Luminescent dye and high-speed camera visualization were used to monitor the partial melting state of an ultrasonically levitated frozen drop exposed to warm environments. Rhodamine B was dissolved (0.01% mass fraction) in the water used to create a droplet. The Droplet was placed at the node of the wave created by the acoustic levitator and frozen via convective cooling. When the cold air flow was turned off, the partial melting of the droplet began. Water droplets with a diameter ranging approximately between 300m to 1800m were tested. Four environmental melting temperatures were tested: 5C, 15C, 25C and 35C. The variation of percentage of partial melting of the drop with time was recorded. The correlation between the rate of melting, environmental temperature, and diameter of the frozen droplets is reported and discussed. It is confirmed that the time rate of melting is inversely proportional to the diameter of the ice crystals and directly proportional to the environmental temperature. An empirical fit to predict the percentage of partial melting with respect to temperature and droplet diameter was experimentally acquired. The models developed in this research can improve the understanding of the physics related to engine icing. In addition, several technologies developed during the effort can be applied to icing wind tunnel testing for the quantification of partial melting.
Download or read book Ice Accretions and Icing Effects for Modern Airfoils written by Harold E. Addy and published by . This book was released on 2000 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Icing tests were conducted to document ice shapes formed on three different two-dimensional airfoils and to study the effects of the accreted ice on aerodynamic performance. The models tested were representative of airfoil designs in current use for each of the commercial transport, business jet, and general aviation categories of aircraft. The models were subjected to a range of icing conditions in an icing wind tunnel. The conditions were selected primarily from the Federal Aviation Administration's Federal Aviation Regulations 25 Appendix C atmospheric icing conditions. A few large droplet icing conditions were included. To verify the aerodynamic performance measurements, molds were made of selected ice shapes formed in the icing tunnel. Castings of the ice were made from the molds and placed on a model in a dry, low-turbulence wind tunnel where precision aerodynamic performance measurements were made. Documentation of all the ice shapes and the aerodynamic performance measurements made during the icing tunnel tests is included in this report. Results from the dry, low-turbulence wind tunnel tests are also presented.
Download or read book Host Bibliographic Record for Boundwith Item Barcode 30112050443578 and Others written by and published by . This book was released on 2013 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:
