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Full-Text Articles in Mechanical Engineering

Aspen Plus Simulation Of Biomass Gasification In A Steam Blown Dual Fluidised Bed, Wayne Doherty, Anthony Reynolds, David Kennedy Aug 2013

Aspen Plus Simulation Of Biomass Gasification In A Steam Blown Dual Fluidised Bed, Wayne Doherty, Anthony Reynolds, David Kennedy

Book/Book Chapters

The efficient utilisation of biomass resources is of utmost importance. Biomass gasification offers much higher efficiencies than combustion. Gasification is a process in which a fuel is converted to a combustible gas (syngas). A dual fluidised bed gasifier known as the fast internally circulating fluidised bed (FICFB) was selected. It has been demonstrated at industrial scale and data is readily available for model validation. An Aspen Plus model was developed to simulate the FICFB gasifier. The model is based on Gibbs free energy minimisation and the restricted equilibrium method was used to calibrate it. The model has been validated and …


Heating Effects Through Harmonic Distortion On Electric Cables In The Built Environment, Kevin O'Connell Jul 2013

Heating Effects Through Harmonic Distortion On Electric Cables In The Built Environment, Kevin O'Connell

Doctoral

Under ideal circumstances, electric power supply voltage and current waveforms should be sinusoidal. However, this is very seldom the case in the built environment, due to the proliferation of non-linear loads. Examples of non-linear loads are those containing switched mode power supplies, reactors and electronic rectifiers/inverters. Common devices such as personal computers, fluorescent lighting, electric motors, variable speed drives, transformers and reactors and virtually all other electronic equipment are examples of non-linear loads. Non-linear loads are the norm in the built environment rather than the exception. Such loads produce complex current and voltage waves and simple spectral analysis of these …


The Effects Of Physical Activity On Greenhouse Gas Emissions For Common Transport Modes In European Countries, Aidan Duffy, Robert Crawford Mar 2013

The Effects Of Physical Activity On Greenhouse Gas Emissions For Common Transport Modes In European Countries, Aidan Duffy, Robert Crawford

Articles

This paper applies a life cycle methodology to estimate activity-related contributions of transport modes to GHG emissions. The methodology uses national input-output tables, environmental accounts, household budget data and nutritional data to derive food-sector GHG coefficients of consumption for ten European countries. The food energy requirements for each mode of transport are estimated taking account of the modal activity level and energy requirements. Walking, cycling, driving and bus travel are considered. Typical national food energy-related emissions for walking, cycling, and driving ranged from 25.6 - 77.3 gCO2-eq/pass.km, 10.4 - 31.4 gCO2-eq/pass.km and 1.7 - 5.2 gCO2-eq/pass.km; passenger transport was found …


State Of The Irish Housing Stock - Modelling The Heat Losses Of Ireland’S Existing Detached Rural Housing Stock & Estimating The Benefit Of Thermal Retrofit Measures On This Stock, Ciara Ahern, Philip Griffiths, Micheal O'Flaherty Jan 2013

State Of The Irish Housing Stock - Modelling The Heat Losses Of Ireland’S Existing Detached Rural Housing Stock & Estimating The Benefit Of Thermal Retrofit Measures On This Stock, Ciara Ahern, Philip Griffiths, Micheal O'Flaherty

Articles

Ireland’s housing stock has been identified as being amongst the least energy efficient in Northern Europe. Consequently, atmospheric emissions are greater than necessary. Government funded schemes have been introduced to incentivise the uptake of thermal retrofit measures in the domestic Irish market. A study of Ireland’s housing highlights the dominance of detached houses (43%), 72% of which are rurally located and are predominantly heated with fuel oil. This paper investigates the economic and carbon case for thermal retrofit measures to the existing detached, oil centrally heated, rural housing stock. The study found the case for energy efficiency measures to be …


Development And Implementation Of A Simplified Residential Energy Asset Rating Model, Daire Reilly, Aidan Duffy, David Willis, Michael Conlon Jan 2013

Development And Implementation Of A Simplified Residential Energy Asset Rating Model, Daire Reilly, Aidan Duffy, David Willis, Michael Conlon

Other resources

In accordance with national and European policies, the provision of financial assistance to residential energy consumers has led to a greater awareness of and interest in energy retrofit technologies. However, at present Irish energy consumers have no appropriate advice on the future performance of retrofit options available to them. This is a significant limitation to decision making and technology uptake, since this group need to know whether their investment is likely to be worthwhile.

The asset rating methodology developed for the certification of energy performance of buildings is the current industry standard of prediction of energy demand and post retrofit …


Transient And Quasi-Steady Thermal Behaviour Of A Building Envelope Due To Retrofitted Cavity Wall And Ceiling Insulation, Aimee Byrne, Gerard Byrne, Anna Davies, Anthony Robinson Jan 2013

Transient And Quasi-Steady Thermal Behaviour Of A Building Envelope Due To Retrofitted Cavity Wall And Ceiling Insulation, Aimee Byrne, Gerard Byrne, Anna Davies, Anthony Robinson

Articles

Accurate understanding of the thermal behaviour of building components is essential for predicting heat-ing or cooling needs and facilitates the implementation of more successful energy saving strategies and retrofits. This paper focuses on a specific measure commonly introduced through the residential energy efficiency retrofit programmes in Ireland–insulation. Traditionally, assessments of the performance of building envelopes have been based on assumed thermal resistances of the materials involved, labora-tory tests and computer modelling. The aim of the present work is to investigate the in situ thermal behaviour of a case study building and its components under transient and quasi-steady environmental conditions, comparing …