Installation Areas Research Articles

Working fluid selection and electrical performance optimisation of a domestic solar-ORC combined heat and power system for year-round operation in the UK

In this paper, we examine the electrical power-generation potential of a domestic-scale solar combined heating and power (S-CHP) system featuring an organic Rankine cycle (ORC) engine and a 15-m2 non-concentrated solar-thermal collector array. The system is simulated with a range of organic working fluids and its performance is optimised for operation in the UK climate. The findings are applicable to similar geographical locations with significant cloud coverage, a low solar resource and limited installation areas. A key feature of the system’s design is the implementation of fixed fluid flow-rates during operation in order to avoid penalties in the performance of components suffered at part-load. Steady operation under varying solar irradiance conditions is provided by way of a working-fluid buffer vessel at the evaporator outlet, which is maintained at the evaporation temperature and pressure of the ORC. By incorporating a two-stage solar collector/evaporator configuration, a maximum net annual electrical work output of 1070kWhyr−1 (continuous average power of 122W) and a solar-to-electrical efficiency of 6.3% is reported with HFC-245ca as the working fluid at an optimal evaporation saturation temperature of 126°C (corresponding to an evaporation pressure of 16.2bar). This is equivalent to ∼32% of the electricity demand of a typical/average UK home, and represents an improvement of more than 50% over a recent effort by the same authors based on an earlier S-CHP system configuration and HFC-245fa as the working fluid [1], thus highlighting the gains possible when using optimal system configurations and fluids and suggesting that significant further improvements may be possible. A performance and simple cost comparison with stand-alone, side-by-side PV and solar-thermal heating systems is presented.

Design guidelines for H-Darrieus wind turbines: Optimization of the annual energy yield

H-Darrieus wind turbines are gaining popularity in the wind energy market, particularly as they are thought to represent a suitable solution even in unconventional installation areas. To promote the diffusion of this technology, industrial manufacturers are continuously proposing new and appealing exterior solutions, coupled with tempting rated-power offers. The actual operating conditions of a rotor over a year can be, however, very different from the nominal one and strictly dependent on the features of the installation site.Based on these considerations, a turbine optimization oriented to maximize the annual energy yield, instead of the maximum power, is thought to represent a more interesting solution. With this goal in mind, 21,600 test cases of H-Darrieus rotors were compared on the basis of their energy-yield capabilities for different annual wind distributions in terms of average speed.The wind distributions were combined with the predicted performance maps of the rotors obtained with a specifically developed numerical code based on a Blade Element Momentum (BEM) approach. The influence on turbine performance of the cut-in speed was accounted for, as well as the limitations due to structural loads (i.e. maximum rotational speed and maximum wind velocity). The analysis, carried out in terms of dimensionless parameters, highlighted the aerodynamic configurations able to ensure the largest annual energy yield for each wind distribution and set of aerodynamic constraints.

Ground source heat pump performance in case of high humidity soil and yearly balanced heat transfer

Ground source heat pump (GSHP) systems are spreading also in Southern Europe, due to their high energy efficiency both in heating and in cooling mode. Moreover, they are particularly suitable in historical cities because of difficulties in the integration of heating/cooling systems into buildings subjected to historical preservation regulations. In these cases, GSHP systems, especially the ones provided with borehole heat exchangers, are a suitable solution instead of gas boilers, air-cooled chillers or cooling towers. In humid soils, GSHP systems are even more interesting because of their enhanced performance due to higher values of soil thermal conductivity and capacity. In this paper, GSHP systems operating under these boundary conditions are analyzed through a specific case study set in Venice and related to the restoration of an historical building. With this analysis the relevant influences of soil thermal conductivity and yearly balanced heat transfer in the design of the borehole field are shown. In particular, the paper shows the possibility to achieve higher compactness of the borehole field footprint area when yearly balanced heat transfer in the borehole field is expected.Then, the second set of results contained in the paper shows how GSHP systems designed for high humidity soils and yearly balanced heat loads at the ground side, even if characterized by a compact footprint area, may still ensure better performance than other available and more common technologies such as boilers, air-cooled chillers, chillers coupled with cooling towers and heat pumps and chillers coupled with lagoon water. As a consequence, in this last comparison, the efficiency of GSHP systems is confirmed even when compact borehole installation areas are used. The analysis is performed in terms of both input energy consumption ratio and primary energy ratio and takes into account the energy consumption of auxiliary devices as well. The conclusions are drawn in terms of percentage, thus allowing the reader to extend the results achieved in this paper to systems operating in other contexts under similar boundary conditions.

PV Systems Installed in Marine Vessels: Technologies and Specifications

Considerations are held about the specificationin whichthe PV plants have to fulfill so that they can be installed on marine vessels. Initially, a brief description of the typical electrical grid of ships is presented, distinguishing the main parts, reporting the typical electrical magnitudes, and choosing the most preferable installation areas. The technical specifications,in whichthe PV plants have to be compatible with, are fully described. They are determined by the special marine environmental conditions, taking into consideration parameters like wind, humidity, shading, corrosion, and limited installation area. The work is carried out with the presentation of the most popular trends in the field of solar cell types and PV system technologies and their ability to keep up with the aforementioned specifications.

Late Preclassic Hohokam Land Use in the Middle Gila River Valley: A View from Florence Military Installation and Adjacent Areas

Late pre-Classic (A.D. 750-1150) Hohokam land use of the middle Gila River Valley in southern Arizona is still poorly understood. Current site distribution data from Florence Military Reservation and adjacent areas indicate that unlike settlement and subsistence behavior existed in lowland and upland, or bajada zones. Early village formation and irrigation technology appear to have first developed in the lowlands, along the Gila River during the early pre-Classic (A.D. 300-750) and subsequently spread to the bajada. By the late pre-Classic, lowland village groups were focused upon irrigation agriculture, while village groups inhabiting the bajada were characterized by a more diverse range of farming strategies, including floodwater (ak chin), dry farming, and perhaps even limited irrigation-based technology. Regionally, late pre-Classic villages were very likely integrated into an interdependent economic system, based upon the presence of ballcourts with presumed marketplaces, where commodities were exchanged. Also, by the late pre-Classic, a degree of Territorial Sedentism existed, with village-based communities inhabiting lowland and bajada zones representing separate territorial units.

A Performance Model for U-Tube Ground-Coupled Heat Exchanger

Because of the great advantages of savings for installation costs and areas of the ground, the ground source heat pump (GSHP) system combined with the ground-coupled heat exchanger with structural member is becoming more and more popular such as energy pile foundation etc.. However, the calculation method especially on the perspective of plate-type ground-coupled heat exchanger (PGHE) has not been established. This paper reports a study on a mathematical model developed to analyze the heat transfer of U-tube plate-type ground-coupled heat exchanger (UPGHE) which combined with structural member and an analytical solution is revealed. The results show that there are clear ‘heat submerge’ for the leg with lower temperature of UPGHE and it is more sensible to arrange one leg apart from another. The results also show that the spacing of pipes have obvious impact on the performance of UPGHE and the temperature difference between two legs have no important effect on the total performance of UPGHE.

Automatic Arrangement Algorithm for Tower Cranes Used in High-rise Apartment Buildings

On most construction sites, the arrangement of tower cranes is decided by site engineers based on their own experience, which can cause cost overruns and delays in the lifting work. Although many researchers have conducted studies on tower crane arrangement using computer modeling and knowledge-based expert systems as well as mathematical models, no research has aimed to develop an algorithm to identify an optimum solution among several alternatives for installation areas of tower cranes satisfying the conditions of lifting work. The objective of this study is to develop an automatic arrangement algorithm for tower cranes used in high-rise apartment construction. First, as a new concept, a possible installation area of tower cranes was suggested. Second, after proposing several alternatives based on the installation points suggested in this study, an algorithm analyzing the economic feasibility of tower cranes was developed considering the rental, installation and removal costs. Third, a case study was conducted to prove the validity of the developed algorithm for selecting and installing an effective set of tower cranes at minimum cost.

Hydrocarbon and Toxic Metal Contamination from Tank Installations in a Northwest Greenlandic Village

Contamination from tank installations in the Arctic is an important issue, since tanks are a necessary feature of all communities, and may be a source of local pollution. Soil samples from below and around three tank installations and one reference site in the Northwest Greenlandic village of Tasiusaq were analysed for the total content of hydrocarbons (THC), lead, cadmium and organic content in the soil. Concentrations up to 77,000 mg/kg DW THC were found, mainly as weathered oil products. Elevated levels of lead and cadmium were also found in many of the samples, with concentrations up to 300 and 2 mg/kg DW, respectively. The tank installation areas were contaminated by THC, lead and cadmium compared to the reference site, and parts of the areas were highly contaminated, exceeding the Danish environmental quality criteria. The correlation between lead and cadmium concentrations was significant (p < 0.01), while no correlation existed between THC and organic matter. Small spills from daily use of the tank installations are suggested to be the source of the THC contamination, whereas the lead and cadmium contamination is suggested to originate primarily from the plume of smoke from waste incineration.

Investigation on air-conditioning load profile and energy consumption of desiccant cooling system for commercial buildings in Hong Kong

In Hong Kong, conventional air-conditioning (AC) systems cause a high energy consumption and poor indoor thermal comfort. This paper investigated the AC load profiles of three typical local commercial buildings, i.e. office, hotel and retail, and examined the energy consumption of liquid desiccant cooling system (LDCS) for these buildings. Simulation results showed that the cooling load contributed to more than 98% of total annual load, with high latent load proportion from March to September. The high reheating ratio, i.e. from 60% to 90%, is found to be the main reason for the poor thermal comfort. Therefore, the LDCS which could handle sensible and latent loads separately was proposed. However, the electricity-driven LDCS was found not suitable for local commercial buildings. significant energy saving could be achieved by the solar-assisted LDCS system with thermal storage, when the installation area for solar collectors is larger than the minimum required one, i.e. 9.7m2/(kWm−2) for office and 12.7m2/(kWm−2) for hotel buildings. Energy saving of different system types with different installation areas was also studied. The solar-assisted LDCS shows more energy saving in winter but less in summer. Results and conclusions can be useful for researchers and local engineers.

Monitoring of deposited particle levels within the museum of Scotland: During and after construction

Abstract Dust deposition and distribution were studied over an 18‐month period during the construction and installation of the Museum of Scotland (MOS) next to the Royal Museum of Scotland (RMS). Deposition levels were assessed by measuring the loss of reflectance of the surface of a clean glass microscope slide. Selected slides were examined by scanning electron microscopy to characterise the phases present. Levels were monitored in the established museum to assess dust ingress during construction. In the new museum, monitoring aimed to assess the effectiveness of containment measures during construction work, installation of displays and cleaning. During installation, dust levels at all sites in the MOS were up to fifteen times greater than those suggested for museums and galleries, with the highest values during the final stages of construction and installation. The major source of dust was ingress of external dust from the building areas to the installation areas, although some local generation of dus...

Applications of nuclear microprobes in the semiconductor industry

Possible nuclear microprobe applications in semiconductor industries are discussed. A unique technique using soft-error mapping and ion beam induced current measurements for reliability testing of dynamic random access memories such as soft-error immunity and noise carrier suppression has been developed for obtaining design parameters of future memory devices. Nano-probes and small installation areas are required for the use of microprobes in the semiconductor industry. Issues arising from microprobe applications such as damage induced by the probe beam are clarified.

Assessment of specific environments by metal piece test kits

To investigate corrosive gases in computer installation areas, we developed an original method called the “Metal piece test kit”. The test kit, which consists of five metal strips—copper, silver, aluminum, iron and iron-nickel alloy—is mounted on an acrylic ☐ that is a little smaller than a cigarette ☐. In this method, this kit is placed in various environments for 1 month. The five metals react with gases and form corrosive products if the environment is contaminated by corrosive gases such as SO 2, H 2S, HCl/NaCl and H 2O as humidity. By comparing the X-ray reflecting intensities of oxygen, sulfur, and chlorine contained in the corrosive products by using an X-ray fluorescence, it is able to predict the environment, determine what kinds of corrosive gases exist and judge if the environment is suited for installation of computers. By using this original method in various computer installation environments, we can adopt a suitable countermeasure to prevent system failure by corrosive gases in the computer installation environment.

Nuclear installations and childhood cancer in the UK: mortality and incidence for 0–9-year-old children, 1971–1980

Data on cancer incidence and mortality in the vicinity of nuclear installations in England and Wales have been published, covering the period 1959–1980. Several age classes and a number of cancer sites have been included. Systematic analysis has so far been limited to cancer mortality. This suggests that childhood leukemia is unusually frequent near some types of installations and the excess is greater for years 0–9 than for later ages. In the earlier decade, 1959–1969, there was questionable consistency of incidence reporting. This report uses the incidence and mortality data only for the period 1971–1980; leukemia and non-leukemia cancer data for those 0–9 years are analyzed, and consistency of incidence reporting is evaluated by comparing incidence and mortality. For comparison with reported data for grouped local authority areas (LAAs) near to 21 different installations, two sources of expected incidence are used. The first is based on regional data, and the second is based on a group of LAAs similar in location, urban/rural character and population size. Effectiveness of treatment of acute lymphocytic leukemia (ALL, the principal type among 0–9-year-old children) has improved in recent decades and this has decreased the case fatality rate, and increased the relevance of incidence data. No significant differences in the mortality/incidence ratio were found when comparing areas near installations with their matched reference areas. Although some standardized incidence ratios (SIRs) are low in comparison areas, these are a reflection of the small numbers in the denominator. Low and high SIRs are observed in both installation and comparison areas. Excluding the populations near Sellafield and Dounreay, the installations of which include nuclear reprocessing and which are reported elsewhere, children living near one of a group of six installations have significantly increased leukemia incidence. One hundred sixty-five cases were observed for the combined population group, whereas 133.6 were expected on the basis of regional data and 141.9 on the basis of comparison areas. The operations of these installations include nuclear research, nuclear fuel production, nuclear weapons manufacture, and radio-isotopic reagent manufacture and marketing. No evidence of any increase of leukemia incidence is found for populations surrounding nuclear power installations, nor in coastal communities possibly affected by Sellafield discharges. In comparing these data with leukemia mortality and with other types of cancer (non-leukemia) mortality and morbidity, an incidental finding was of significantly elevated non-leukemia mortality in the vicinity of a group of nuclear power installations, based on comparison but not on regional data (24 observed cases, 25.7 expected on basis of regional data, 10.6 on the basis of comparison area data). Due to small numbers, no specific cancer site can be found to account for this, and it may be an artifactual finding. These contrast with the findings of Cook-Mozaffari et al.'s regression analysis of mortality which showed a positive, but not significant association for leukemia among residents near nuclear power plants. This study confirms Cook-Mozaffari et al.'s findings by mortality analysis for the group of installations involved in non-power producing nuclear technology. This study sheds no light on the possible basis for the association, which remains to be clarified. Initial steps have been taken by Gardner et al. using case-referent methods.

Copper deterioration in a water distribution system of a county hospital in Germany caused by microbially induced corrosion – I. Description of the problem

AbstractA severe copper corrosion process in the water distribution system of a County Hospital has been detected in the cold and warm water sections shortly after the opening of the Hospital. The damaged copper pipes showed pitting corrosion phenomena that could not be attributed to known types of pitting. The results of a first sampling revealed the same kind of corrosion in all installation areas. A thorough examination of the samples (perforations and hole depths) proved an influence of design and operating conditions on the extent of corrosion.The analysis of the corrosion products showed that some products could be attributed to microbial activities in the copper pipes. A polymeric layer, the so‐called “biofi”, could be detected beneath the corrosion products. The presence of a biofilm indicates microbially induced corrosion. First countermeasures are being taken in the County Hospital to prevent further damages.

Cancer near nuclear installations.

The OPCS report on cancer incidence and mortality in the vicinity of nuclear installations in England and Wales provides a mass of information that is so large that it should be possible to detect quite small changes in disease levels with considerable confidence. The data on cancer mortality are less subject to selective bias than the registration data on which incidence rates are based, and they provide the firmest grounds on which evidence of any effect can be obtained. These data show conclusively that there has been no general increase in cancer mortality in the vicinity of nuclear installations in a 22-year period beginning several years after the opening of the installations that have released the largest amounts of radionuclides to the environment. On the contrary, the mortality from cancer has tended to be lower in the LAAs in the vicinity of nuclear installations than in control LAAs selected for their presumed comparability with the former. This is unlikely to be due to a protective effect of ionizing radiation and suggests that, despite the efforts that were made to choose comparable control areas, there were non-installation differences between the populations relevant to the risk of dying from one or other type of cancer. Detailed examination of the few types of cancer that were relatively more common in the installation areas suggest that several of the differences were most likely to be due to chance, diagnostic artefacts or social factors rather than to any hazard specifically related to the installations. One disease provides a possible exception: namely, leukaemia in the age group 0-24 years. Two other diseases need further investigation, multiple myeloma and Hodgkin's disease in the older age group 25-74 years. The excess mortality rates recorded from these cancers were not large, and it has yet to be established that they are not due to general confounding by other environmental or socio-economic factors.

Cable Tray Installation for Process Plants

The function of a tray system in a process plant is to provide an efficient wiring method for power, lighting, instrumentation, communications, and grounding. This paper reviews tray system design, material selection, installation, and problem areas. The presentation is based on experience in the design and installation of complete tray systems for oil refineries, chemical plants, and power plants.