Other resources

Just Let Me Fly

Jim McGovern — Fri, 10 Jun 2011 01:40:59 PDT

‘Just Let Me Fly’ is a three act play by Jim McGovern. The underlying genre is tragedy with some dry humour and incidental music. The main theme is academic rivalry and the feeling of being repressed or bullied. The context is a department of aeronautical engineering at a university. An audio play variant is also available: ‘Fly Faster.’

The main character, Leonard Twiglet, is a middle-aged Reader in Aeronautical Engineering at the University of Selfridge. Between the spring of 2003 and the autumn of 2004 Leonard experiences a crisis that, without his realizing it, has been building up for years.

The play also takes an irreverent look at some engineering, academic and commercial attitudes and practices. However, for those without any nerdish-technocrat sympathies, it might just be one to miss!

Fly Faster

Jim McGovern — Fri, 10 Jun 2011 01:35:03 PDT

‘Fly Faster’ is an audio play by Jim McGovern. The underlying genre is tragedy with some dry humour and incidental music. The main theme is academic rivalry and the feeling of being repressed or bullied. The context is a department of aeronautical engineering at a university. The play also takes an irreverent look at some engineering, academic and commercial attitudes and practices. It may contain some technical terms! A full three-act stage play variant is also available: ‘Just Let Me Fly.’

Leonard Twiglet runs a propeller-propulsion research grouping, called APPEAL, from the Department of Aeronautical Engineering at the University of Selfridge. Professor Alex Graybell, the Head of the Department, leads a much stronger Jet Engine Research Consortium, JERC.

Marine Current Energy Status and it's Potential in Ireland

Fergal O'Rourke et al. — Thu, 19 Nov 2009 02:32:30 PST

The energy consumption in Ireland is primarily achieved by the combustion of fossil fuels. As well as fossil fuels continually becoming more expensive and fluctuating in price, their use as an energy source also has a negative impact on the environment. Ireland’s energy consumption can be separated into three separate divisions: transportation, electricity generation and heat energy. The use of marine current energy technologies will assist in sustainable development as well as being a solution to several energy related environmental problems. Energy extraction using this technology offers a vast and predictable energy source. However, marine current energy technology is still not economically viable on a large scale, due to the current stage of development. This paper presents Ireland’s current energy requirements, future targets, drivers for the deployment of renewable energy technologies and potential marine current energy extraction sites. Cost estimates are also analysed and the leading marine current energy extraction devices are discussed.

The Very Basics of Sustainability - an Alternative Viewpoint

Jim McGovern — Mon, 31 Aug 2009 05:01:26 PDT

This paper examines the context and meaning of the term ‘sustainability’, the factors that determine and govern climate on Earth, the population of the Earth and its trends and influencers, the requirements for sustaining life and the options that are available to humankind. Some viewpoints are presented that are alternative to ‘conventional alternative’ thinking. 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’ and also argues that humankind needs to face up to the population size that the Earth can sustain and the desired sustainable distribution of wealth.

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 — Wed, 26 Aug 2009 02:57:46 PDT

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 is required.

The Role of Computer Simulation in the Context of Zero-emission Power Plants

Jim McGovern — Wed, 08 Jul 2009 02:43:41 PDT

The role of computer simulation in the context of zero-emission power plants is outlined. The use of computer simulation models to simulate zero-emission power plants in fine detail is strongly recommended.

Simulation and parametric analyses of a tubular solid oxide fuel cell stack using aspen plus

Wayne Doherty et al. — Thu, 02 Jul 2009 02:19:58 PDT

In the context of climate change and increasing energy conversion efficiency solid oxide fuel cells (SOFCs) are likely to play an important role in the production of electricity. The tubular SOFC configuration is considered to be the most advanced and is approaching commercialisation. A major advantage of SOFCs over other types of fuel cells is that they can utilise a wide spectrum of fuels (natural gas, coal and biomass syn-gas). This is due to its high operating temperature, which also makes them suitable for integration with gas turbines and for cogeneration. A R&D project is underway to develop a computer simulation model of a tubular SOFC that can accurately predict performance under various conditions and using a range of fuels. A model is developed using the process simulator aspen plus. The software uses unit operation blocks, which are models of process operations. The user places these blocks on a flowsheet, specifying material and energy streams. There is no built in model that can represent a SOFC, however it is possible to construct one using the built in unit operation blocks. This method is an alternative to developing a fuel cell model using programming languages. The model is based on Gibbs free energy minimisation. Data available in the literature on the Siemens Power Generation tubular SOFC was used to validate the model. The model predicts thermodynamic condition and chemical composition of the stack exhaust gases, heat generated, voltage, current, and electrical efficiency. Fuel composition and operating parameters were varied over a wide range. Operating parameters such as fuel utilisation factor, current density, and steam to carbon ratio were found to have significant influence. In a future study this SOFC stack model will be integrated with a biomass gasifier model and balance of plant models all developed in aspen plus. From examination of the sensitivity analyses’ results optimum conditions are established.

Combined heat and power in the Irish market

Barry Cullen et al. — Thu, 11 Jun 2009 06:47:01 PDT

Combined Heat and Power (CHP) production offers significant benefits in terms of energy efficiency and CO2 abatement and is generally considered to be a key technology in the move towards sustainable energy in Ireland. As a distributed generation technology it immediately benefits from reduced transmission and distribution losses, and as a combined generator its total plant efficiency indicates a significant decrease in fuel costs and a reduction in harmful emissions. The corresponding positive effect on energy security through reduced consumption is notable also. It therefore holds a significant place in the country’s future energy strategy. The present work offers a brief detail of the principles of CHP generation and the advantages, disadvantages and barriers to the implementation of the technology. Current government incentives in Ireland are examined and their success described. The importance of the energy balance and the economic value of the different energy types produced by the CHP unit are detailed. Reference is made to ongoing work in the Dublin Institute of Technology aimed at altering the balance of the energy outputs of a typical CHP unit in favour of electrical power.

Solar energy conversion through seaweed photosynthesis with combustion in a zero-emission power plant

Evgeny Yantovski et al. — Mon, 27 Apr 2009 08:07:24 PDT

A proposed ‘closed cycle’ power plant scheme, referred to as SOFT (Solar Oxygen Fuel Turbine), is described. The scheme involves the cultivation of macroalgae in a pond, combustion of their organic matter in a fluidised bed boiler that generates steam for a Rankine cycle steam power plant and the return of the combustion products to the pond to feed the algae. Oxygen, equivalent to that used for combustion, is re-released to the atmosphere by photosynthesis, while the carbon dioxide that is produced by combustion is absorbed by photosynthesis and thereby recycled.

It is proposed that the seaweed Ulva, which is common in Irish coastal waters, can be used in the solar pond. The solar energy conversion efficiency is less than that which can be achieved by the use of photovoltaic panels, but the energy expenditure to construct algae ponds as solar energy receivers is much less. Therefore the proposed scheme can be economically, as well as environmentally, attractive. For a power unit of 100 kW the pond surface area in Ireland would be about 6 hectares.

Heat pump evaluation and design for the Irish climate

Jim McGovern — Wed, 03 Dec 2008 06:39:50 PST

The work of this thesis concerns the application of heat pumps to domestic space heating in Ireland. Only small air-source electric-powered vapour compression plants using fluorocarbon refrigerants are considered.

Tests have been carried out on an air-to-air heat pump unit with a rated heat output of 3 kW. The performance characteristics of each of the system components have been determined from the test results.

Computer programs have been written to calculate performance figures for theoretical heat pump cycles and refrigerants 12, 22 and 502 have been compared with one another on the basis of theoretical performance.

A computer program has been written to simulate the performance of a heat pump plant given the performance characteristics of the system components and the operating conditions. An extension of this program allows the seasonal performance of a heat pump installation to be predicted.

The measured performance of the unit tested was very poor, but, it has not been determined whether or not specially designed heat pumps could compete with other forms of heating in Ireland. However, it is felt that the simulation program provides a useful means of optimising heat pump designs for Irish conditions. This step is essential to their evaluation.

On refrigerant compressors

Jim McGovern — Mon, 15 Sep 2008 07:14:44 PDT

The purpose of the work was to critically re-examine and investigate the evaluation of refrigerant compressors and to determine and discriminate between the factors which influence their characteristics. The objectives also included the investigation of techniques by which the characteristics can be established and the suggestion of ways in which compressor performance can be described and quantified.

The particular compressor which was tested was of the reciprocating open type.

Existing theories relating to the efficiency of displacement utilisation are extended to yield an overall framework in which the various influences can be described and quantified.

Conventional parameters for the quantification of shaft power utilisation are reviewed critically and alternatives are presented and justified. These alternatives are rational efficiencies based on the Second Law of Thermodynamics.

Load stands and specialised measurement techniques for testing refrigerant compressors are reviewed. A design rationale for the load stand which was built and used for compressor testing is presented.

The load stand was a bypass type which involved full condensation of part of the flow and a mixing process. The operating conditions of the compressor were controlled by means of throttle valves only.

Data illustrating the main characteristics of the compressor which was tested, i.e. mass flow rate, shaft power, discharge temperature and oil concentration in the discharge vapour, are presented over a range of speeds and over a range of suction superheat values.

In addition, many parameters of the compressor which underlie its performance characteristics are presented graphically versus speed and versus suction temperature. Dynamic measurements of cylinder pressure and valve displacements are presented, analysed and discussed.

The displacement utilisation efficiency of the compressor is presented and the losses in displacement utilisation are quantified discretely under five headings.

The test data did not allow full discrimination between heat transfer, leakage and solubility effects within the cylinder and the measurement difficulties are discussed in detail. The concept of a 'phantom mass' of refrigerant which dissolves and re-emerges from solution in the lubricating oil is conjectured and discussed.

The indicated rational efficiency of the compressor is presented graphically. Data describing indicated work, the suction pumping work and the discharge pumping work are also presented, as are data describing the overall heat transfer rate during compression and the time averaged plenum heat transfer rates. It is concluded that thermodynamic availability analysis is essential to the understanding of the factors underlying shaft power utilisation.

The outputs of a compressor simulation model are compared with test results. The characteristics of the compressor which was tested were found to be generally favourable for the purposes of capacity control by speed variation.

In conclusion, new ways of looking at the utilisation of shaft power and of volume displacement are presented along with many other new ideas relating to the evaluation of refrigerant compressors.