Hot-water aquifer storage: A field test

The basic water injection cycle used in a large-scale field study of heat storage in a confined aquifer near Mobile, Alabama is described. Water was pumped from an upper semi-confined aquifer, passed through a boiler where it was heated to a temperature of about 55 C, and injected into a medium sand confined aquifer. The injection well has a 6-inch (15-cm) partially-penetrating steel screen. The top of the storage formation is about 40 meters below the surface and the formation thickness is about 21 meters. In the first cycle, after a storage period of 51 days, the injection well was pumped until the temperature of the recovered water dropped to 33 c. At that point 55,300 cubic meters of water had been withdrawn and 66 percent of the injected energy had been recovered. The recovery period for the second cycle continued until the water temperature was 27.5 C and 100,100 cubic meters of water was recovered. At the end of the cycle about 90 percent of the energy injected during the cycle had been recovered

Thermal energy storage in a confined aquifer: Second cycle

This is the published version. Copyright 1981 American Geophysical UnionDuring the first 6-month injection-storage-recovery cycle of the Auburn University Aquifer Thermal Energy Storage Project, water pumped from an upper supply aquifer was heated to an average temperature of 55°C with an oil-fired boiler and then injected into a lower storage aquifer. Injection and recovery temperatures, flow rates, and temperatures at six depths in 10 observation wells and hydraulic heads in seven wells were recorded twice daily. The second-cycle injection, which was performed in a manner similar to the first, began on September 23, 1978, and continued until November 25, 1978, when 58,010 m3 of water had been pumped into the storage aquifer. The major problem experienced during the first cycle, a clogging injection well, was reduced by regular backwashing. This was done 8 times during injection and resulted in a 24% average injection rate increase compared to the first cycle. A 63-day storage period ended on January 27, 1979, and production of hot water began with an initial temperature of 54°C. By March 23 this temperature had dropped to 33°C, with 66,400 m3 of water and 76% of the injected thermal energy recovered. This compares to 66% recovery during the first cycle over the same drop in production temperature. Production of hot water continued until April 20, at which time 100,100 m3 of water and 89% of the injected thermal energy was recovered at a final production temperature of 27.5°C. During the second cycle, measurements were made of relative land subsidence and rebound to a precision approaching 0.1 mm. The surface elevation near the injection well rose 4 mm during injection, fell during storage, and fell more rapidly toward its original elevation during production. This movement was due to thermal expansion and contraction rather than to effects caused by head changes in the storage aquifer

Thermal energy storage in a confined aquifer: Experimental results

This is the published version. Copyright 1979 American Geophysical UnionTo aid in testing the idea of storing thermal energy in aquifers, an experiment was performed by Auburn University in which 54,784 m3 of water was pumped from a shallow supply aquifer, heated to an average temperature of 55°C, and injected into a deeper confined aquifer where the ambient temperature was 20°C. After a storage period of 51 days, 55,345 m3 of water were produced from the confined aquifer. Throughout the experiment, which lasted approximately 6 months, groundwater temperatures were recorded at six depths in each of 10 observation wells, and hydraulic heads were recorded in five observation wells. In order to prevent errors due to thermal convection, most of the observation wells recording temperature had to be backfilled with sand. During the 41-day production period, the temperature of the produced water varied from 55° to 33°C, and 65% of the injected thermal energy was recovered. At no time was an appreciable amount of free thermal convection observed in the storage formation. The dominant heat dissipation mechanisms appeared to be hydrodynamic thermal dispersion and possible mixing of cold and hot water induced by clogging and unclogging of the injection-production well. On the basis of laboratory and field studies, it was concluded that clogging of the injection well, which constituted the major technical problem during the experiment, was caused by the freshwater-sensitive nature of the storage aquifer. Due to the relatively low concentration of cations in the supply water, clay particles would swell, disperse, and migrate until they became trapped in the relatively small pores connecting the larger pores. Surging the pump and back washing the injection well would dislodge the clogging particles and temporarily improve the storage formation permeability. The phenomenon seems largely independent of temperature because it was reproduced in the laboratory with unheated water. It may, however, depend on pore velocity. Future research should be directed toward procedures for selecting storage aquifers that will have minimal susceptibility to clogging and other geochemical problems. Procedures for overcoming such difficulties are needed also because clogging and related phenomena will be more the rule than the exception. Designing an aquifer thermal storage system for maximum energy recovery would involve selecting an appropriate aquifer, analyzing the effects of hydrodynamic thermal dispersion and thermal convection if it is predicted to occur, anticipating geochemical problems, designing the optimum supply-injection-production well configuration and injecting a sufficiently large volume of heated water to realize economies of scale related to increasing volume-surface area ratio

The Production of Hospitable Space: Commercial Propositions and Consumer Co-Creation in a Bar Operation

This paper examines the processes through which a commercial bar is transformed into a hospitable space. Drawing on a study of a venue patronized by lesbian, gay, bisexual and transsexual/transgender consumers, it considers how social and commercial forms of hospitality are mobilized. The paper argues that hospitable space has an ideological, normative and situational dimension. More specifically, it suggests the bar’s operation is tied to a set of ideological conceptions, which become the potential basis of association and disassociation among consumers. It examines the forces and processes that shape who participates in the production and consumption of hospitality and how. Finally, it considers the situational, emergent nature of hospitality and the discontinuous production of hospitable space. Rather than focusing exclusively on host-guest or provider-customer relations, which dominates existing work on hospitality, the paper examines how consumers’ perceptions, actions and interactions shape the production of hospitality. By doing so the paper offers an alternative approach to understanding queer spaces, bar operation as well as hospitality

The social affordances of flashpacking: exploring the mobility nexus of travel and communication

The proliferation of digital devices and online social media and networking technologies has altered the backpacking landscape in recent years. Thanks to the ready availability of online communication, travelers are now able to stay in continuous touch with friends, family and other travelers while on the move. This article introduces the practice of ‘flashpacking’ to describe this emerging trend and interrogates the patterns of connection and disconnection that become possible as corporeal travel and social technologies converge. Drawing on the concepts of ‘assemblages’ and ‘affordances’, we outline several aspects of this new sociality: virtual mooring, following, collaborating, and (dis)connecting. The conclusion situates this discussion alongside broader questions about the shifting nature of social life in an increasingly mobile and mediated world and suggests directions for future research at the intersection of tourism and technology

The ‘digital glimpse’ as imagining home

This paper proposes the concept of the ‘digital glimpse’, which develops the existing framing of imaginative travel. Here it articulates the experiences of mobile workers digitally connecting into family life and everyday rituals when physically absent with work. The recent embedding of digital communication technologies into personal relationships and family life is reconfiguring how absence is experienced and practiced by workers on the move, and through this, new digital paradigms for life on-the-move are emerging. This paper explores how such social relationships are maintained at-a-distance through digital technology – using evidence from qualitative interviews with mobile workers and their families. Digital technology now enables expressive forms of ‘virtual travel’, including video calling, picture sharing, and instant messaging. This has implications for the ways in which families can manage the social and relational pressures of being apart. Experiences of imaginative travel created through novel media can enrich the experience and give a greater sense of connection for both those who are at home and those who are away. While technology is limited in its ability to replicate a sense of co-presence, ‘digital glimpses’ are an emergent set of sociotechnical practices that can reduce the negative impact of absence on family relationships

Tourism as connectedness.

Late modernity in developed nations is characterized by changing social and psychological conditions, including individualization, processes of competition and loneliness. Remaining socially connected is becoming increasingly important. In this situation, travel provides meaning through physical encounters, inclusion in traveller Gemeinschaft based on shared norms, beliefs and interests, and social status in societies increasingly defined by mobilities. As relationships are forged and found in mobility, travel is no longer an option, rather a necessity for sociality, identity construction, affirmation or alteration. Social contexts and the underlying motivations for tourism have changed fundamentally in late modernity: non-tourism has become a threat to self-conceptions. By integrating social and psychological perspectives, this paper expands and deepens existing travel and mobilities discussions to advance the understanding of tourism as a mechanism of social connectedness, and points to implications for future tourism research

Aberrant Insertion of the Right Subclavian Artery: an Unusual Cause of Dysphagia in an Adult

Contains fulltext : 79615.pdf (publisher's version ) (Closed access

Structural changes to primary visual cortex in the congenital absence of cone input in achromatopsia

Autosomal recessive Achromatopsia (ACHM) is a rare inherited disorder associated with dysfunctional cone photoreceptors resulting in a congenital absence of cone input to visual cortex. This might lead to distinct changes in cortical architecture with a negative impact on the success of gene augmentation therapies. To investigate the status of the visual cortex in these patients, we performed a multi-centre study focusing on the cortical structure of regions that normally receive predominantly cone input. Using high-resolution T1-weighted MRI scans and surface-based morphometry, we compared cortical thickness, surface area and grey matter volume in foveal, parafoveal and paracentral representations of primary visual cortex in 15 individuals with ACHM and 42 normally sighted, healthy controls (HC). In ACHM, surface area was reduced in all tested representations, while thickening of the cortex was found highly localized to the most central representation. These results were comparable to more widespread changes in brain structure reported in congenitally blind individuals, suggesting similar developmental processes, i.e., irrespective of the underlying cause and extent of vision loss. The cortical differences we report here could limit the success of treatment of ACHM in adulthood. Interventions earlier in life when cortical structure is not different from normal would likely offer better visual outcomes for those with ACHM