1,721,380 research outputs found
The development of a novel large area building integrated solar collector for pool heating
No full textUnglazed solar collectors have often been used a means of providing low cost heating to swimming pools. However, these systems are typically polymer style “mats” that are laid on top of a roof, often leading to poor aesthetics due to their lack of integration with the building itself. This study charts the development of a novel large area unglazed building integrated solar pool heating system (BIT), based on long run sheet metal roofing, from its initial conceptualisation through to its implementation. It discusses the design of the building integrated solar collector modules, the assessment of their performance through theoretical modelling and experimental validation. Subsequently, it shows the scaling of laboratory scale testing to a large area array through modelling and discusses the performance of the system in the “as-built” configuration. In doing this, it provides a succinct illustration of the design process for the development of the University of Waikato’s building integrated pool heating system
Performance of a building integrated collector for solar heating and radiant cooling
No full textDue to their limited temperature range, unglazed solar collectors have long been relegated to providing low cost heating in applications such as swimming pool heating systems. This limited temperature range is due to heat loss: firstly by convection to the surrounding air and secondly by radiant heat transfer to the cold sky. During the day an unglazed collector can be operated as a standard solar absorber to heat water in a storage tank. However, it is possible to take advantage of radiant cooling of unglazed solar collectors by operating them at night. Under night conditions when there is no solar radiation and the sky temperature is low, the collector can radiate heat to the sky and cool a cold storage tank to provide cooling in the building the following day.
This study theoretically and experimentally examines the performance of a building integrated collector for heating and cooling and explores the contribution it can make to heating and cooling loads in typical New Zealand and Australian buildings
Fabrication and Experimental Studies of a Hybrid Flat Plate Solar Collector for Heating Pool Water
Get PDFWarm water in swimming pool is more of a necessity than comfort in places where temperature drops down below 25°C during winter. So pool water heaters are used extensively at places like Hotels, Hospitals, and Clubs etc. to bring the water temperature to a comfort level. But conventional pool water heaters require a lot of energy (electrical/fossil fuel energy) to run. Laws have been enforced in many countries which restrict the use of direct electricity to heat pool water.
This project report gives a detailed outline of the fabrication procedure of a flat plate solar thermal collector, built out of locally available materials. The report also contains the experimentation work carried out with the Collector model to determine its efficiency and optimum parameters. A brief solar surveying work was carried out during the project which has been explained. Finally, a feasible and economic heating system design is proposed which takes into account the temperature data of the water and air collected from NIT Rourkela swimming pool and the qualitative aspects of the fabricated flat plate solar collector
Do Patent Pools Encourage Innovation? Evidence from the 19th-Century Sewing Machine Industry
Get PDFMembers of a patent pool agree to use a set of patents as if they were jointly owned by all members and license them as a package to other firms. Regulators favor pools as a means to encourage innovation: Pools are expected to reduce litigation risks for their members and lower license fees and transactions costs for other firms. This paper uses the example of the first patent pool in U.S. history, the Sewing Machine Combination (1856-1877) to perform the first empirical test of the effects of a patent pool on innovation. Contrary to theoretical predictions, the sewing machine pool appears to have discouraged patenting and innovation, in particular for the members of the pool. Data on stitches per minute, as an objectively quantifiable measure of innovation, confirm these findings. Innovation for both members and outside firms slowed as soon as the pool had been established and resumed only after it had dissolved.
Solar Swimming Pool Heating in Florida: Collector Sizing and Economics
Get PDFThere are over 300,000 swimming pools in Florida, and most of them must be heated during winter months to maintain comfortable swimming conditions. For the average user, temperatures ranging from 78 °F to 80° F for spring and fall and 76° for winter are usually considered comfortable. This publication presents a simple method that can be used to determine the solar collector area (within ± 20 percent) needed to heat a swimming pool to comfort conditions assuming average weather patterns
A Study of Java Demographics
Get PDFResearchers have long strived to exploit program behaviour in order to improve garbage collection efficiency. For example, by using a simple heuristic, generational GC manages short-lived objects well, although longer-lived objects will still be promoted to an older generation and may be processed repeatedly thereafter. In this paper, we provide a detailed study of Java object lifetimes which reveals a richer landscape than the generational view offers. Allocation site has been claimed to be a good predictor for object lifetime, but we show that object lifetime can be categorised more precisely than 'short-lived/long-lived/immortal'. We show that (i) sites allocate objects with lifetimes in only a small number of narrow ranges, and (ii) sites cluster strongly with respect to the lifetime distributions of the objects they allocate. Furthermore, (iii) these clusterings are robust against the size of the input given to the program and (iv) are likely to allocate objects that are live only in particular phases of the program's execution. Finally, we show that, in contrast to previous studies, (v) allocation site alone is not always sufficient as a predictor of object lifetime distribution but one further level of stack context suffices
Status of the NASA-Lewis flat-plate collector tests with a solar simulator
Get PDFSimulator test results of 15 collector types are presented. Collectors are given performance ratings according to their use for pool heating, hot water, absorption A/C or heating, and solar Rankine machines. Collectors found to be good performers in the above categories, except for pool heating, were a black nickel coated, 2 glass collector, and a black paint 2 glass collector containing a mylar honeycomb. For pool heating, a black paint, one glass collector was found to be the best performer. Collector performance parameters of 5 collector types were determined to aid in explaining the factors that govern performance. The two factors that had the greatest effect on collector performance were the collector heat loss and the coating absorptivity
Estudo experimental da ebulição nucleada em superfícies cilíndricas lisa e ranhurada /
Get PDFDissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico
Thermal Performance of Hybrid Solar Swimming Pool and Heating of Building in Kirkuk City-Iraq
Get PDFIn the latest development, a solar hybrid system maintains the outdoor pool at a constant 30°C year-round. Solar energy, a crucial renewable energy source, is harnessed through a novel collector design emphasizing the importance of tourism designs and heating concepts with environmental considerations. The technology, widely used in homes, involves measuring unglazed flat solar collectors (3.12 m2) for outdoor dome swimming pools in winter. A 2 m2- collector was integrated into a building and studied for seven daily hours over three months (December, January, and February). The internal heating system relied on a fan for electrical energy, reaching peak efficiency in February. Operating at 700 W/m2 radiation intensity and a 0.16 kg/sec flow rate, parameters such as sun intensity, ambient temperature, pond water conditions, solar output, water flow, and humidity were recorded. Thermal losses from the pool were calculated using a flat, oval-shaped tube solar collector, along with the room temperature after the pool had stabilized. The results showed a 0.16 kg/s flow rate optimized collector efficiency, prioritizing these findings for achieving thermal comfort, effective building heating, and preserving indoor pool temperature
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