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Full-Text Articles in Engineering

Mathematical Modelling Of A Low Approach Evaporative Cooling Process For Space Cooling In Buildings, Medhi Nasrabadi, Donal Finn, Ben Costelloe Jan 2012

Mathematical Modelling Of A Low Approach Evaporative Cooling Process For Space Cooling In Buildings, Medhi Nasrabadi, Donal Finn, Ben Costelloe

Conference Papers

This paper describes a mathematical model of a low approach open evaporative cooling tower for the production of high temperature indirect cooling water (14-16°C) for use in building radiant cooling and displacement ventilation systems. There are several potential approaches to model evaporative cooling, including: the Poppe method, the Merkel method and the effectiveness-NTU (ε-NTU) method. A common assumption, applied to the Merkel and ε-NTU methods, is that the effect of change in tower water mass flow rate due to evaporation is ignored, which results in a simpler model with reduced computational requirements, but with somewhat decreasedaccuracy. In this paper, a …


2:1 The Paper Tube Project, Noel Brady Jan 2012

2:1 The Paper Tube Project, Noel Brady

Articles

Review of applied technological solution to rapid building techniques using paper tube and analogous materials to create space enclosing geodesic systems.


Life Cycle Costing Template (Excel), Dermot Kehily Dec 2011

Life Cycle Costing Template (Excel), Dermot Kehily

Reports

No abstract provided.


Stochastic Hybrid Embodied Co2-Eq Analysis: An Application To The Irish Apartment Building Sector, Adolf Acquaye, Aidan Duffy, Biswajit Basu Apr 2011

Stochastic Hybrid Embodied Co2-Eq Analysis: An Application To The Irish Apartment Building Sector, Adolf Acquaye, Aidan Duffy, Biswajit Basu

Articles

Although embodiedCO2-eq analysis has seen recent developments as evident in the establishment of the ISO14040 and 14044 LCA standards, it is recognized that due to weaknesses in gathering data on product-related emissions,embodiedCO2-eq values are probabilistic. This paper presents a stochastic analysis of hybrid embodied CO2-eq in buildings to account for this weakness in traditional methods and, by way of example, applies it to an Irish construction-sector case study. Using seven apartment buildings, 70,000 results are simulated with Monte Carlo analysis and used to derive probabilistic and cumulative embodied CO2-eq intensity distributions for apartment buildings in Ireland. A Wakeby distribution with …


Projected Costs Of A Grid-Connected Domestic Pv System Under Different Scenarios In Ireland, Using Measured Data From A Trial Installation, Lacour Ayompe, Aidan Duffy, Sarah Mccormack, Michael Conlon Apr 2010

Projected Costs Of A Grid-Connected Domestic Pv System Under Different Scenarios In Ireland, Using Measured Data From A Trial Installation, Lacour Ayompe, Aidan Duffy, Sarah Mccormack, Michael Conlon

Articles

This paper presents results of a study of projected costs for a grid-connected PV system for domestic application in Ireland. The study is based on results from a 1.72kWpPV system installed on a flat rooftop in Dublin, Ireland. During its first year of operation a total of 885.1kWh/kWp of electricity was generated with a performance ratio of 81.5%. The scenarios employed in this study consider: a range of capital costs; cost dynamics based on a PV module learning rate of 2+/-75%; projections for global annual installed PV capacity under an advanced and moderate market growth conditions; domestic electricity cost growth …


The Very Basics Of Sustainability - An Alternative Viewpoint (Slides With Audio) (Large File! To Speed Up Download, Right-Click On "Download" Link To Save To Own Pc.), Jim Mcgovern Aug 2009

The Very Basics Of Sustainability - An Alternative Viewpoint (Slides With Audio) (Large File! To Speed Up Download, Right-Click On "Download" Link To Save To Own Pc.), Jim Mcgovern

Other resources

This presentation sets out the very basics of ‘sustainability’, although a definition of sustainability is not attempted. Some of the very basics are the context in which the Earth and humankind exist in space and time, the Earth’s climate, the Earth’s population and humankind’s options and choices. The author advocates keeping an open mind on all available options, including the use of oil, gas, coal, tar sands, carbon capture and sequestration, nuclear power etc., as well as the technologies that are more widely considered ‘green’. The author also argues that, in addressing the challenges that humankind faces, globally concerted effort …


Assessment Of The Embodied Co2eq In Buildings Towards A Sustainable Building Design And Construction, Adolf Acquaye, Aidan Duffy, Biswajit Basu Jul 2009

Assessment Of The Embodied Co2eq In Buildings Towards A Sustainable Building Design And Construction, Adolf Acquaye, Aidan Duffy, Biswajit Basu

Conference Papers

Research studies have shown that the initial energy embodied in a building can be as much as 67% of the operational energy over a 25 year period. With growing global concerns over material and resource consumption and the emissions of CO2 into the atmosphere, the energy embodied in buildings constructed in town and cities becomes important and one of the key issues that needs to be tackled in the design stages in order to strive towards sustainable buildings design. In this paper, a hybrid embodied carbon dioxide equivalent (CO2eq) methodology used to assess the CO2eq embodied in buildings is presented. …


Heat Transfer Correlations For Low Approach Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn Jan 2009

Heat Transfer Correlations For Low Approach Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn

Articles

The experimental performance of an open industrial scale cooling tower, utilising small approach temperature differences (1–3 K), for rejection of heat at the low water temperatures (11–20 °C) typical of chilled ceilings and other sensible air–water heat dissipation systems in buildings, is examined. The study was carried out under temperate maritime climatic conditions (3–18 °C wet-bulb temperature range). Initially a theoretical analysis of the process at typical conditions for this climate was conducted, which indicated that a water to air (L/G) mass flow rate ratio of less than 1.0 was required for effective operation. Consequently for these low L/G ratios, …


The Application Of Web 2.0 Technologies As An Experimental Method Of Teaching Remote Sensing At Dit, Ireland, Avril Behan Jul 2008

The Application Of Web 2.0 Technologies As An Experimental Method Of Teaching Remote Sensing At Dit, Ireland, Avril Behan

Conference Papers

This paper describes the implementation of an experimental method of delivery for a module of remote sensing material to second year students on the BSc (Hons) in Geomatics at the Dublin Institute of Technology. The project began as a reaction to poor levels of student engagement and unsatisfactory grades, as well as the requirement to focus more on real-world type problems due to the implementation of a work-placement semester for third year students. Both pedagogical considerations (movement towards formative feedback, interactivity and group-based work) and the effect of technological drivers, such as the popularity of the internet in general and …


Metrology And Proportion In The Ecclesiastical Architecture Of Medieval Ireland, Avril Behan, Rachel Moss Jun 2008

Metrology And Proportion In The Ecclesiastical Architecture Of Medieval Ireland, Avril Behan, Rachel Moss

Conference Papers

The aim of this paper is to examine the extent to which detailed empirical analysis of the metrology and proportional systems used in the design of Irish ecclesiastical architecture can be analysed to provide historical information not otherwise available. Focussing on a relatively limited sample of window tracery designs as a case study, it will first set out to establish what, if any, systems were in use, and then what light these might shed on the background, training and work practices of the masons, and, by association, the patrons responsible for employing them.


Thermal Effectiveness Characteristics Of Low Approach Indirect Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn Jan 2007

Thermal Effectiveness Characteristics Of Low Approach Indirect Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn

Articles

Meteorological enthalpy analysis of temperate and maritime climates above latitude 45°N suggests that the water-side evaporative cooling technique has considerable unrealised potential with contemporary “high temperature” building cooling systems—such as chilled ceilings and displacement ventilation. As low approach conditions are the key to exploiting the cooling potential of the ambient air, thermal performance at such conditions needs to be investigated. To address the research issues, an industrial scale test rig, based on a low approach open cooling tower and plate heat exchanger and designed to maximise evaporative cooling potential, has been constructed. The thermal effectiveness of such systems (as a …


Thermal Performance Of Low Approach Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn Apr 2006

Thermal Performance Of Low Approach Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn

Conference Papers

Meteorological enthalpy analysis of temperate and maritime climates above 45˚N suggests that the water-side evaporative cooling technique has considerable unrealised potential with contemporary "high temperature" building cooling systems - such as chilled ceilings. As low approach conditions are the key to exploiting the cooling potential of the ambient air, thermal performance at such conditions needs to be investigated. To address the research issues a test rig, based on an open cooling tower and plate heat exchanger and designed to maximise evaporative cooling potential, has been constructed at DIT. A combination of experimental measurement and analysis is used in the investigations. …


Thermal Efficiency Characteristics Of Indirect Evaporative Cooling Systems, Ben Costelloe, Donal Finn May 2005

Thermal Efficiency Characteristics Of Indirect Evaporative Cooling Systems, Ben Costelloe, Donal Finn

Conference Papers

Recent developments in enhancing heat transfer in cooling towers, together with the success of chilled ceilings, have prompted a review of the evaporative cooling technique. in temperate maritime climates. The thermal efficiency of such systems is a key parameter, as a measure of the degree to which the system has succeeded in exploiting the cooling potential of the ambient air. This paper presents the results of experimental research into the thermal efficiency of a water-side open indirect evaporative cooling test rig designed to achieve low (1-4 K) approach conditions. Secondary efficiencies in the range 0.24-0.76 have been achieved.


Experimental Energy Performance Of Open Cooling Towers Used Under Low And Variable Approach Conditions For Indirect Evaporative Cooling Of Buildings, Ben Costelloe, Donal Finn Jan 2003

Experimental Energy Performance Of Open Cooling Towers Used Under Low And Variable Approach Conditions For Indirect Evaporative Cooling Of Buildings, Ben Costelloe, Donal Finn

Articles

The success of chilled ceilings and displacement ventilation systems as a means of sensible cooling in buildings has prompted a review of evaporative cooling technology as an effective means of generating the required cooling water. When such cooling water is generated at low approach conditions (2–5 K), at the higher temperatures required in these systems (14–18°C), very high levels of availability result. In many north western European locations the levels of availability are such that the prospect of supplanting rather than simply supplementing the refrigeration system, for sensible cooling purposes, arises. The viability of the technique, however, largely depends on …


Energy Performance Of Indirect Evaporative Cooling In Chilled Ceiling Applications In Maritime Temperate Climates, Ben Costelloe, Donal Finn Jan 2003

Energy Performance Of Indirect Evaporative Cooling In Chilled Ceiling Applications In Maritime Temperate Climates, Ben Costelloe, Donal Finn

Conference Papers

Evaporative cooling has had limited application in maritime, temperate, climates due to the low levels of cooling water availability which result, when low temperature (5 to 8˚C), convection based, building cooling systems are used. However, the success of "high temperature" radiant cooling, in the form of chilled ceilings, has prompted a review of evaporative cooling in maritime, temperate, conditions. In order to maximize evaporative cooling availability, however, in this application, it is necessary to achieve low wet bulb temperature approach conditions, at viable levels of primary energy consumption. This paper presents the results of experimental research into the energy performance …


Indirect Evaporative Cooling Potential In Air-Water Systems In Temperate Climates, Ben Costelloe, Donal Finn Jan 2003

Indirect Evaporative Cooling Potential In Air-Water Systems In Temperate Climates, Ben Costelloe, Donal Finn

Articles

Recent developments have prompted a review of evaporative cooling technology as an effective means of cooling modern deep plan buildings. Prominent among these developments is the success of high temperature sensible cooling systems, particularly, chilled ceilings, which require a supply of cooling water at 14–18 °C. Crucial to the success of evaporative cooling technology, as a significant means of cooling in modern applications, is the ability to generate cooling water, in an indirect circuit, at a temperature which closely approaches the ambient adiabatic saturation temperature (AST) or wet bulb temperature (WBT). Recent experimental research has demonstrated that it is technically …


Research Into Evaporative Cooling Of Buildings In Maritime Climates, Ben Costelloe, Donal Finn Sep 2002

Research Into Evaporative Cooling Of Buildings In Maritime Climates, Ben Costelloe, Donal Finn

Reports

Concern with environmental emissions has focused attention on traditional forms of energy use in buildings, with a view to reducing and making more rational use of energy consumption. One area of concern is the traditional, refrigeration based, commercial air conditioning system, which has high levels of electrical power consumption in fans and refrigeration compressors. There is also concern among building owners and design teams, supported by the PROBE series of post occupancy studies, conducted by the CIBSE, that many buildings, with traditional forms of air conditioning, under perform in terms of occupant satisfaction, ease of operation and control, maintenance costs …


Developments In Evaporative Cooling Of Buildings In Maritime Climates, Ben Costelloe, Donal Finn Jul 2002

Developments In Evaporative Cooling Of Buildings In Maritime Climates, Ben Costelloe, Donal Finn

Reports

Concern with environmental emissions has focused attention on traditional forms of energy use in buildings, with a view to reducing and making more rational use of energy consumption. One area of concern is the traditional, refrigeration based, commercial air conditioning system, which has high levels of electrical power consumption in fans and refrigeration compressors. There is also concern among building owners and design teams, supported by the PROBE series of post occupancy studies, conducted by the CIBSE, that many buildings, with traditional forms of air conditioning, under perform in terms of occupant satisfaction, ease of operation and control, maintenance costs …


Evaporative Cooling Availability In Water Based Sensible Cooling Systems, Ben Costelloe, Donal Finn Sep 2001

Evaporative Cooling Availability In Water Based Sensible Cooling Systems, Ben Costelloe, Donal Finn

Conference Papers

Recent developments have prompted a review of evaporative cooling technology as an effective means of cooling modern deep plan buildings. Prominent among these developments is the success of high temperature sensible cooling systems, such as chilled ceilings, which require a supply of cooling water at 14 to 18°C. Crucial to the success of evaporative cooling technology, as a significant means of cooling in modern applications, is the ability to generate cooling water, in an indirect circuit, at a temperature which closely approaches the ambient adiabatic saturation temperature or wet bulb temperature. Recent research in this area has shown that it …


The Design And Performance Of An Evaporative Cooling Test Rig For A Maritime Climate, Ben Costelloe, Donal Finn Sep 2000

The Design And Performance Of An Evaporative Cooling Test Rig For A Maritime Climate, Ben Costelloe, Donal Finn

Conference Papers

Recent developments have prompted a review of the use of cooling tower based evaporative cooling technology as an effective means of cooling modern buildings. Prominent among these developments is the success of high temperature cooling systems such as radiant ceiling panels and chilled beams. At present, however, there is little published literature which gives a quantitative, in depth analysis of the performance or energy efficiency of cooling towers, used in maritime climates, in conjunction with heat exchangers and run at low approach and low wet bulb temperatures throughout the free cooling season. This lack of knowledge has meant that many …