Mechanical Engineering Commons^™

The Effect Of Air Preheating In A Biomass Cfb Gasifier Using Aspen Plus Simulation, Wayne Doherty, Anthony Reynolds, David Kennedy

Articles

In the context of climate change, increasing efficiency and energy security, biomass gasification is likely to play an important role in energy production. Atmospheric circulating fluidised bed (CFB) technology was selected for the current study. The primary objective of this research is to develop a computer simulation model of a CFB biomass gasifier that can accurately predict gasifier performance under various operating conditions. An original model was developed using ASPEN Plus (Advanced System for Process ENgineering Plus). The model is based on Gibbs free energy minimisation. The restricted equilibrium method was used to calibrate the model against experimental data. This …

Modelling And Simulation Of A Biomass Gasification-Solid Oxide Fuel Cell Combined Heat And Power Plant Using Aspen Plus, Wayne Doherty, Anthony Reynolds, David Kennedy

Conference Papers

In this paper the operation and performance of a high temperature solid oxide fuel cell (SOFC) stack on biomass syn-gas from a demonstration biomass gasification combined heat and power (CHP) plant is investigated. The objective of this work is to develop a computer simulation model of a biomass-SOFC CHP system, flexible enough for use in industry, capable of predicting system performance under various operating conditions and using diverse fuels. The biomass gasifier is of the dual fluidised bed (DFB) type with steam as the gasifying agent and is operated at atmospheric pressure. The tubular SOFC configuration, developed by Siemens Power …

Analysis Of Wear Models For Advanced Coated Materials, Simon Montgomery, David Kennedy, Noel O'Dowd

Conference Papers

Tribological tests, mathematical modelling and simulations have been conducted over the last few decades to investigate the nature and effects of mechanical wear in coated and uncoated materials. Mathematical models have been developed and in unison with specifically designed empirical tests, the veracity/capability of these models has been investigated. In more recent cases advanced engineering analysis tools, such as FEA and DOE, are used to further compliment and refine experimental techniques.

Studies have focused on the various wear mechanisms: abrasion, adhesion, erosion, corrosion wear, fatigue wear and also on different combinations of these. The intrinsic importance of the material in …

Alternative Sources Of Energy, David Kennedy

Conference Papers

Ireland relies on imports of fossil fuels for up to 83% of its energy needs and this statistic is relatively common in other European countries. Apart from the high import costs and pollutions associated with fossil fuels and the need to meet new targets in terms of CO2 emissions, energy security is essential. This paper provides an overview and outline of the different alternative energy sources available for use either at domestic or on large scale production, some of which are established and others less likely to succeed in our climate.
Some of the alternative energy sources such as wind …

Localised Galvanic Corrosion Processes In Thermal Spray Coated/Cast Aluminium Alloy Systems, David Culliton, Tony Betts, David Kennedy

Conference Papers

Cast Aluminium Alloys, because of the propensity of aluminium to react with impurities and alloying elements, are prone to developing IM impurities during the solidification process. These IM phases can act, in some fluids, as initiation sites for localised corrosion processes, resulting in degradation phenomena, such as pitting. Whilst Thermal Spray coatings can improve the wear resistance of Cast Aluminium Alloys, their corrosion performance may be hampered by the presence of through porosity within the coating.

The present work details some preliminary studies of the localised corrosion processes occurring at the interface area between a Thermal Spray coating and a …

International Energy Agency Bestest For Ground Coupled Heat Transfer, Joel Neymark, Ron Judkoff, Michael Crowley

Reports

The objective of this project is to assess the accuracy of building energy analysis tools that have incorporated detailed models for predicting ground-coupled heat transfer related to floor slab and basement constructions. An executive summary is to be found in the main report.

Exploitation Of Surface Engineering Technology Research, David Kennedy

Conference Papers

Surface engineering refers to a wide range of technologies that design and modify the surface properties and characteristics of components. The applications are very broad from macro to nano and from extremely hard materials to polymeric coatings. The uses are found in many engineering, energy, gas and oil, transport, medical, cosmetic, optical, chemical and sports industries. Research in this technology is ongoing and the benefits that can be derived are enormous. The design, wear and tribological properties of components for instance have been greatly enhanced by surface engineering and the economic benefits to industries far outweigh the cost and use …

The Effect Of Vibratory Milling On The Powder Properties Of Zinc Oxide Varistors, Maura Kelleher, M.S.J. Hashmi

Articles

The formation of powders from multi-elemental oxides for the subsequent formation of a green and sintered compact body is a major processing operation in the manufacture of ZnO varistors. The physical and chemical properties of the metal oxides are crucial not only for the formation of a varistor component with optimum microstructure and thus electrical characteristics but also for avoiding the introduction of flaws and reduced yield during subsequent manufacturing stages. The effect of vibratory milling using cylindrical zirconia media on the physical and chemical properties of the mixed multi-elemental oxide additives of a commercial ZnO varistor formulation was studied. …

An Analysis Of The Performance Of Foams Used In Hurling Helmets, Keith Norris, Stephen Tiernan

Conference Papers

Abstract Head injuries can occur in most sporting activities. The seriousness of these injuries can vary greatly depending on the sport. Many sports such as American football, cricket, baseball and hurling try to reduce this risk by designing helmets that are suitable to be worn by the players. The National Standard Authority of Ireland (NSAI) has recently made great strides in this area with the introduction of the first comprehensive standard adopted for the sport I.S. 355:2006, which sets out new testing procedures that all new helmets must meet. The Gaelic Athletic Association (GAA) has also stated its intention to …

Robots Assist In Treatment Of Stroke Patients, Philip Deering, David Kennedy, James Conlon

Articles

Robotic rehabilitation is a field of biomedical engineering which combines precise mechanical design with control technology through the interaction of medical and engineering professionalss to produce a new tool in medical rehabilitation. This article provides an overview of an interactive robot for the medical rehabilitation of stroke victims.

Numerical Prediction Of Primary And Secondary Flows In A Ranque-Hilsch Vortex Tube, Ronan Oliver

Masters

The primary aim of this project is to obtain a fundamental understanding of the fluid dynamics and thermodynamics of the primary and secondary flows in a Ranque-Hilsch Vortex Tube (RHVT). These flows are highly complex and are three dimensional, compressible and viscous in nature. To obtain an understanding of these, a state of the art Computational Fluid Dynamics (CFD) software package is applied for flow prediction with advanced turbulence models, and is employed to predict the primary and secondary flows in a RHVT. The models that are used include : the k-e model, the SST model by Menter, and the …

Force Measurement And Evaluation For Surgical Cutting Applications: Development Of An Effective Characterisation Testbed, Dean Callaghan

Conference Papers

Sensorized instruments that cater for accurate measurement of the interaction forces (between biological tissue and instrument end-effector) during surgical procedures offer surgeons a greater sense of immersion during minimally invasive robotic surgery (MIRS). There is much ongoing research into force measurement/evaluation involving surgical graspers. However, comparatively little corresponding effort has been expended in the measurement and subsequent evaluation of forces between scissor blades and tissue. This paper presents the design and development of a force/strain measurement test apparatus, which will ultimately serve as an effective sensor characterisation and evaluation platform. Data acquired from the testing platform can be used to …

Preparation And Accreditation Of Level 7 Engineering Programmes, Mark Mcgrath

Conference Papers

Accreditation of 3^rd level educational programmes by a suitably recognised professional body is of particular relevance in relation to engineering. The completion of a sequence of modules which leads to the attainment of this professionally recognised award is viewed as integral to the undertaking. The engineering technology fields are developing and expanding rapidly and the third level sector must keep abreast of these changes. This is essential if the third level institutions wish to continue delivering programmes which produce graduates who can successfully complete the transition from 3rd. Level to the various engineering sectors.

This paper outlines various aspects …

Time And Pitch Scale Modification: A Real-Time Framework And Tutorial, Dan Barry, David Dorran, Eugene Coyle

Conference papers

A framework is presented which is designed to address the issues related to the real-time implementation of time-scale and pitch scale modification algorithms. This framework can be used as the basis for the developments of applications which allow for a seamless real-time transition between continually varying time scale and pitch-scale parameters which arise as a result of manual or automatic intervention.

Design Issues For Therapeutic Ultrasound Angioplasty Waveguides, Declan Noone, Graham Gavin, Garrett Mcguinness

Conference Papers

Therapeutic ultrasound angioplasty is a new minimally invasive cardiovascular procedure for disrupting atherosclerotic lesions. Mechanical energy is transmitted in the form of ultrasound waves via long, flexible wire waveguides navigated to the lesion site through the vascular system. The underpinning principle of this technology is that plaque may be disrupted through a combination of direct contact ablation, pressure waves, cavitation and acoustic streaming, which all depend on the amplitude and frequency of displacements at the distal tip of the wire waveguide. This study identifies a number of key design issues for clinical devices of this type, and describes testing procedures …

Simulation Of A Circulating Fluidised Bed Biomass Gasifier Using Aspen Plus: A Performance Analysis, Wayne Doherty, Anthony Reynolds, David Kennedy

Conference Papers

In the near future biomass gasification is likely to play an important role in energy production and conversion. Its application has great potential in the context of climate change mitigation, increasing efficiency and energy security. Atmospheric circulating fluidised bed (CFB) technology was selected for the current study. An original computer simulation model of a CFB biomass gasifier was developed using ASPEN Plus (Advanced System for Process ENgineering Plus). It is based on Gibbs free energy minimisation and the restricted equilibrium method was used to calibrate it against experimental data. This was achieved by specifying the temperature approach for the gasification …

Mechanical Engineering Education In Irish Context: On Route To Becoming A Chartered Engineer, David Kennedy, Richard Good

Conference Papers

Engineering Education in Ireland and throughout Europe has changed dramatically over the last few years and the pace of change is ensuring that we, the educators are constantly keeping abreast of new developments and benchmarks. Programmes that were based on inputs from learners are now outcomes based and the onus is on the educators and facilitators to provide evidence that graduates are capable of conducting specific tasks, commonly termed as Programme Outcomes. Similarly, greater onus is now placed on the learner to take greater responsibility for their educational development. The new and current process of meeting the educational requirements of …

Thermal Testing Of Building Insulation Materials, Eoghan Frawley, David Kennedy

Articles

This article explores the testing of building insulation materials and the development of a suitable testing apparatus.

Investigation Into The Possible Use Of An Oxygen Ion Transport Membrane Combustion Unit In An Oxyfired Power Plant, Kirsten Foy

Doctoral

It is generally recognised that carbon dioxide (CO2) emissions damage the environment. Carbon capture and storage offers the possibility of using fossil fuels for power production without releasing C02. In the proposed ZEITMOP power plant cycle hydrocarbon fuel is burned in a mixture of oxygen and C02, allowing easy separation of combustion products to capture the C02 for sequestration. Oxygen ion transport membranes (OTMs) provide oxygen. The original configuration of the cycle requires an OTM air separation unit, in which oxygen is separated from air and mixed with CO2, and a separate combustion chamber, in which fuel is burned in …

Treating Water Contamination Using Ultraviolet Radiation To Control Cryptosporidium And E.Coli, Michael O'Hehir, David Kennedy, Thomas Dunphy

Articles

Concerns about the quality of drinking water in Ireland have come into sharp focus with the recent Cryptosporidium outbreak in Galway City. This article looks at how ultraviolet radiation can offer a potential solution in the control of Cryptosporidium contamination.

Introducing New Engineering Students To Mechanical Concepts Through An “Energy Cube” Project, Micheal O'Flaherty, Shannon Chance, Fionnuala Farrell, Christopher Montague

Conference papers

The objective of this paper is to describe a problem based learning module, called the “Energy Cube”, offered by Technological University Dublin that is designed to teach mechanical, building services and manufacturing engineering concepts to first year engineering students.

The Energy Cube project gives students hands-on experience in areas ranging from heat transfer, lighting and energy efficiency to industrial and product design. In the Energy Cube, students design and construct (using cardboard, clear plastic, and glue) a model of a building that admits as much daylight as possible while being energy efficient and aesthetically pleasing.

The students, working in teams …

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 …

Slow Flow Between Concentric Cones, O. Hall, C. P. Hills, A. D. Gilbert

Articles

This paper considers the low-Reynolds-number flow of an incompressible fluid contained in the gap between two coaxial cones with coincident apices and bounded by a spherical lid. The two cones and the lid are allowed to rotate independently about their common axis, generating a swirling motion. The swirl induces a secondary, meridional circulation through inertial effects. For specific configurations complex eigenmodes representing an infinite sequence of eddies, analogous to those found in two-dimensional corner flows and some three-dimensional geometries, form a component of this secondary circulation. When the cones rotate these eigenmodes, arising from the geometry, compete with the forced …

Thermal Control Of An Occupied Room: Investigating The Use Of Carbon Dioxide Concentration As An Auxiliary Control Variable, Kevin O'Connell, Aidan O'Dwyer

Conference papers

This paper details the theoretical and experimental work done in the examination of the relationship between human generated carbon dioxide concentration and temperature rise in an occupied room. Generation of carbon dioxide by humans is linked to metabolic rate and heat generation. Therefore, carbon dioxide concentration may be used as an indicator of occupancy in a room. Typically, a heating control system will react slowly to changes in room occupancy if temperature is used as the process variable. The aim of the work was to establish if carbon dioxide concentration in the space could be used as an auxiliary control …

Exchange Faculty Perspectives On International Collaborations, Donal Mchale

Conference Papers

The main purpose of the paper is to document key issues in developing successful transatlantic faculty exchanges and to document perspectives and key learnings’ emanating from the development and implementation of an international exchange process.

Solar Energy Conversion Through Seaweed Photosynthesis With Combustion In A Zero-Emission Power Plant, Evgeny Yantovski, Jim Mcgovern

Other resources

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 …

Indentation Fracture Of Bovine Cortical Bone: Acoustic Emission Technique, Ashkan Safari, Ger Reilly, Brendan Mccormack

Conference Papers

Indentation cutting may result in microcracking and main crack growth which was previously reported. In this study, we recorded the AE signals produced by cracking processes during cutting on cortical bone, measuring the cutting force and correlating between load-displacement curves and AE activities.

A Numerical Acoustic Fluid-Structure Simulation Of Therapeutic Ultrasound Angioplasty, Graham Gavin, Finbar Dolan, M.S J. Hashmi, Garrett Mcguinness

Conference Papers

INTRODUCTION Therapeutic ultrasound angioplasty is the delivery of high amplitude ultrasonic displacements to the distal-tip of small diameter wire waveguides with the goal of disrupting atherosclerotic plaques. This is a minimally invasive procedure that may have potential' in the treatment of complicated chronic total occlusions. The disruption of plaque is due to direct contact ablation and also cavitation, pressure waves and acoustic streaming in the fluid surrounding the vibrating waveguide distal-tip [1]. Cavitation appears to play a major role and some authors have suggested that plaque ablation is only evident above the cavitation threshold [2]. Makin and Everbach [3] performed …

Reducing Energy Costs By Optimizing Controller Tuning, Aidan O'Dwyer

Conference papers

The proportional integral derivative (PID) controller is the most dominant form of automatic controller in industrial use today. With this technique, it is necessary to adjust the controller parameters according to the nature of the process. This tailoring of controller to process is known as controller tuning. Controller tuning is easily and effectively performed using tuning rules (i.e. formulae for controller tuning, based on process information). Such tuning rules allow the easy set up of controllers to achieve optimum performance at commissioning. Importantly, they allow ease of re-commissioning if the characteristics of the process change. The paper outlines the results …

A Numerical Acoustic Fluid-Structure Model Of A Therapeutic Ultrasound Angioplasty Device, Graham Gavin, M.S. J. Hashmi, Finbar Dolan, Garrett Mcguinness

Conference Papers

Ultrasonic angioplasty involves the use of ultrasonic vibrations delivered to the distal-tip of small diameter wire waveguides and is an emerging technology the may have potential use in the treatment of complicated atherosclerotic plaques during cardiovascular surgery. Complicated plaques, including chronic total occlusions and calcified lesions, seriously reduce success rates during standard intervention involving guidewire access, followed by balloon dilation or stent delivery. The large amplitude (0-150 μm) wire waveguide distal-tip displacements in the low-frequency ultrasonic (18-45 kHz) range have been shown to disrupt plaque material by direct contact ablation and cavitation, acoustic streaming and pressure wave components in adjacent …