Mechanical Engineering Commons^™

Sustainability Matchmaking: Exploration Into Using Excess Renewable Energy To Deliver ‘Free’ Energy To Fuel Poor Homes – A Preliminary Case Study In Ireland, Ciara Ahern, Ronan Oliver

Articles

The aggregated fuel cost of domestic hot water (DHW) generation in Ireland, in 2022, was €529M with associated emissions/load of 1.3MtCO₂/289GWh. The shadow price of carbon monetises the negative impact of emissions, rising with time; DHW generation has an associated shadow carbon cost of €13M in 2022, rising to €42M in 2030 and €335M in 2050.

In 2020, c12%/€441M of wind was curtailed or wasted as inter alia, there was no demand at times of high wind. Meanwhile, a ‘silent crisis’ is occurring in Ireland wherein one-in-two dwellings were considered in fuel poverty in 2022. Households in …

Addressing Low Heat Pump Heating System Sales In The Uk, Ben Costelloe

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The replacement of existing fossil fuel boilers with heat pumps is seen as a key measure in the decarbonisation of heating systems and addressing climate change. This policy however, is currently failing in many Western European states, particularly in the UK. The many reasons for this situation are examined. However, the age of UK housing stock and particularly the high number of dwellings built prior to the introduction of building insulation regulations in 1980, are key. To maintain the running cost of air source heat pumps competitive with those of the gas boilers they generally replace the heat pump lift …

Energy-Specific Greenhouse Gas Emissions Measurements From 2-Stroke Marine Diesel Engine Using Liquefied Natural Gas, Kang-Ki Lee, Wilfried Hochegger, Alessandro Schonborn

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This study reports the energy specific air emissions from a diesel-cycle high pressure injection dual fuel engine for operation on liquefied natural gas and heavy fuel oil. An experiment at sea was performed onboard a bulk carrier during commercial voyages, to measure the efficiency of the engine and to measure air emissions relevant to air pollution and climate impact for operation on both fuels. The measurements showed that the energy conversion efficiency of the engine was higher for operation on liquefied natural gas because its lower NOx emissions permitted the use of a higher effective compression ratio whilst meeting the …

3d Simulation Of A Yogurt Filling Machine Using Grafcet Studio And Factory Io: Realization Of Industry 4.0, Bashir Salah, Waqas Saleem, Razaullah Khan, Ahmed Tawhid Ahmed Soliman

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Manufacturing systems, enterprises and academic institutions worldwide are implementing industry 4.0 (IR4.0). By integrating the services and equipment, IR4.0 develops autonomous systems that manage industrial operations and exchange real-time data in real time. This study includes a simulation of an existing production system using the GRAFCET Studio software.

Cfd Simulation Of Anaerobic Granular Sludge Reactors: A Review, Camila D' Bastiani, David Kennedy, Anthony Reynolds

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Anaerobic digestion processes can generate renewable energy in the form of biogas while treating organic wastewater. The generation of biogas within anaerobic digestion systems is directly linked to the mixing conditions inside the reactors. In high-rate reactors such as the up-flow anaerobic sludge blanket (UASB) reactor, the expanded granular sludge bed (EGSB) reactor and the internal circulation (IC) reactor, the hydrodynamic behaviour will depend on the interactions between the wastewater, the biogas, and the biomass granules. Over the past few years, various researchers have used computational fluid dynamics (CFD) to study the hydrodynamic behaviour in these types of reactors. This …

Advances In Precision Microfabrication Through Digital Light Processing: System Development, Material And Applications, Xinhui Wang, Jinghang Liu, Yang Zhang, Per Magnus Kristiansen, Aminul Islam, Michael Gilchrist, Nan Zhang

Articles

Digital Light Processing (DLP) is an advanced additive manufacturing technology which has garnered substantial recognition and has been extensively applications in various fields. This review focuses on the precision microfabrication process of DLP, providing an overview of the DLP 3D printing system, including the digital light engine, project lenses, motorised stage and resin vat for micro-structure fabrication. Additionally, this review paper comprehensively analyses commercially available DLP printers, covering resolution, cost and a detailed discussion on the importance of photopolymer resins, emphasising the monomer, photo-initiator, photoabsorber, etc. Based on the photopolymerisation theory, the DLP high-precision printing process is analysed, which is …

Tidal Current Turbine Blade Optimisation With Improved Blade Element Momentum Theory And A Non-Dominated Sorting Genetic Algorithm, Eng Jet Yeo, David Kennedy, Fergal O'Rourke

Articles

Tidal current energy has the advantage of predictability over most of the other renewable energy resources. However, due to the harsh operating environment and complicated site conditions, developments in this domain have been gradual. Paramount to these points is device design and optimisation of hydrodynamic performance. Recent developments in the correction models of BEM theory have further improved the accuracy of the prediction model. Using an improved blade element momentum theory model that is capable of accurately capturing the downwash angle and combining it with a well-developed and reliable non-dominated sorting genetic algorithm model, an effective and efficient tidal current …

Building Performance - Societal Drive, Programme And Symposium, Joseph Little, Patrick Daly

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Society is increasingly looking at the construction industry to mitigate the environmental crisis and solve the housing crisis through wholesale embrace of three broad sets of challenges. The MSc in Building Performance (Energy Efficiency in Design) (MSc BP(EED)) was created in 2017 to provide significant upskilling in the knowledge, skills, and software applications of building design professionals so that they can meet these challenges, while creating compliant, sustainable, super-low energy, new and renovated buildings. The delivery of the programme supports upskilling of employed building design professionals at Masters level, encouraging a minority to develop their capacity and interest in research …

In-Flow Dynamics Of An Area-Difference-Energy Spring-Particle Red Blood Cell Model On Non-Uniform Grids, Brendan Walsh, Fergal Boyle

Articles

In this paper the area-difference-energy spring-particle (ADE-SP) red blood cell (RBC) structural model developed by Chen and Boyle is coupled with a lattice Boltzmann flux solver to simulate RBC dynamics. The novel ADE-SP model accounts for bending resistance due to the membrane area difference of RBCs while the lattice Boltzmann flux solver offers reduced computational runtimes through GPU parallelisation and enabling the employment of non-uniform meshes. This coupled model is used to simulate RBC dynamics and predictions are compared with existing experimental measurements. The simulations successfully predict tumbling, tank-treading, swinging and intermittent behaviour of an RBC in shear flow, and …

Experimental Investigation Of The Performance Of A Hybrid Self-Healing System In Porous Asphalt Under Fatigue Loadings, Shi Xu, Liu Xueyan, Amir Tabakovic, Erik Schlangen

Articles

Self-healing asphalt, which is designed to achieve autonomic damage repair in asphalt pavement, offers a great life-extension prospect and therefore not only reduces pavement maintenance costs but also saves energy and reduces CO2 emissions. The combined asphalt self-healing system, incorporating both encapsulated rejuvenator and induction heating, can heal cracks with melted binder and aged binder rejuvenation, and the synergistic effect of the two technologies shows significant advantages in healing efficiency over the single self-healing method. This study explores the fatigue life extension prospect of the combined healing system in porous asphalt. To this aim, porous asphalt (PA) test specimens with …

Deployment And Control Of Adaptive Building Facades For Energy Generation, Thermal Insulation, Ventilation And Daylighting: A Review, Hani Alkhatib, Philippe Lemarchand, Brian Norton, Dominic O'Sullivan

Articles

A major objective in the design and operation of buildings is to maintain occupant comfort without incurring significant energy use. Particularly in narrower-plan buildings, the thermophysical properties and behaviour of their façades are often an important determinant of internal conditions. Building facades have been, and are being, developed to adapt their heat and mass transfer characteristics to changes in weather conditions, number of occupants and occupant’s requirements and preferences. Both the wall and window elements of a facade can be engineered to (i) harness solar energy for photovoltaic electricity generation, heating, inducing ventilation and daylighting (ii) provide varying levels of …

A Generalisable Bottom-Up Methodology For Deriving A Residential Stock Model From Large Empirical Databases., Ciara Ahern, Brian Norton

Articles

Average reference dwellings representing a predominant housing typology are defined in this work. Specifying such reference buildings is a prerequisite for (i) calculating cost-optimal energy performance requirements for buildings and building elements and (ii) ensuring valid calculations of national building energy consumption. In the EU, an Energy Performance Certificate (EPC) rating is an assessment of the energy consumption of a dwelling. The use of inappropriate default-values for the building envelope thermal transmittance coefficients (U-values) and standardised thermal bridging transmittance coefficients (Y-values) in the production of EPCs leads to an over-estimation of potential energy savings from interventions in the existing dwelling …

The Application Of Evolutionary Algorithms In Multi-Objective Design And Optimization Of Air Cooled Heatsinks, Younis Osama Abdelsalam, Sajad Alimohammadi, Tim Persoons

Articles

Genetic algorithms (GAs) are considered to be one of the main types of evolutionary algorithms (EAs) and are being increasingly used in various engineering design applications. To a large extent, plate-fin heatsinks are used in the thermal management of compact electronic equipment and data centers. The shape optimization of the heatsinks is not rigorously investigated during the design process of high power electronics. Any improvements in the effectiveness of the heatsinks impact the energy consumed by large-scale information communication technology (ICT) facilities including data centers and telecommunication systems and promote a more sustainable use of raw materials. This paper investigates …

Three-Phase Hydrodynamic Simulation And Experimental Validation Of An Upflow Anaerobic Sludge Blanket Reactor, Camila D' Bastiani, Jéferson Luis Alba, Gabriel Tomazzoni Mazzarotto, Severino Rodrigues De Farias Neto, Anthony Reynolds, David Kennedy, Lademir Luiz Beal

Articles

This research focuses on performing multiphase solid/liquid/gas CFD simulations of a UASB reactor in order to obtain a validated model that provides a clearer understanding of the hydrodynamic behaviour of the three phases in UASB reactors. Eulerian–Eulerian, laminar, three-dimensional, multiphase simulations are carried out using Fluent 16.2. The liquid phase velocity and flow profile are validated through PIV experiments. A liquid mean velocity difference of 8.45% is found between the experimental and numerical results, thus validating the CFD model. Shadowgraphy is applied successfully to validate the biogas phase velocity and bubble size. Based on the hydrodynamic analysis results, the reactor …

A Novel Self-Healing System: Towards A Sustainable Porous Asphalt, Shi Xu, Xueyan Liu, Amir Tabakovic, Erik Schlangen

Articles

Self-healing asphalt, aimed to produce a sustainable asphalt pavement using green technology, has been studied in the past two decades. Technologies including encapsulated rejuvenator and induction heating have been proposed, demonstrated in the laboratory, and gradually evaluated in field application. This paper looks into the synergy effect of the above two technologies, where induction heating serves as the asphalt damage repair mechanism, requiring just 2 min heating time and encapsulated rejuvenator will replenish (rejuvenate) aged asphalt binder and reinstate bitumen’s healing ability. Moreover, the increased temperature from induction heating could in turn accelerate the diffusion process of rejuvenator into aged …

A Preconditioned Lattice Boltzmann Flux Solver For Steady Flows On Unstructured Hexahedral Grids, Brendan Walsh, Fergal Boyle

Articles

The lattice Boltzmann flux solver (LBFS), first introduced by Shu et al. (2014) on structured meshes, allows fluid flow problems to be solved on unstructured meshes discretised by the finite volume method. The solver calculates the macroscopic fluxes at the cell interfaces from a local reconstruction of the lattice Boltzmann solution. In this paper the LBFS is extended to three-dimensional unstructured hexahedral meshes and a preconditioned lattice Boltzmann flux solver (PLBFS) is presented. The PLBFS involves applying the preconditioning technique proposed by Guo (2004) to the LBFS and is achieved by modifying the equilibrium distribution function used to calculate the …

Carbon-Based Interlayers In Perovskite Solar Cells, Aleksandr P. Litvin, Xiaoyu Zhang, Kevin Berwick, Anatoly V. Fedorov, Weitao Zheng, Alexander V. Baranov

Articles

Perovskites are solution-processed, high-performance semiconductors of interest in low-cost photovoltaics. The interfaces between the perovskite photoactive layers and the top and bottom contacts are crucial for efficient charge transport and minimizing trapping. Control of the collection of charge carriers at these interfaces is decisive to device performance. Here, we review recent progress in the realization of efficient perovskite solar cells using cheap, easily processed, stable, carbon-based interlayers. Interface materials including graphene, carbon nanotubes, fullerenes, graphene quantum dots and carbon dots are introduced and their influence on device performance is discussed.

Cognitive Performance In Midlife Type 2 Diabetes: Results Form The Enbind Study, A. H. Dyer, L. Mckenna, G. Gamage, N. M. Bourke, Isabelle Killane, M. Widdowson, C. P. Woods, J. Gibney, R. Reilly, D. O'Neill, S. P. Kennelly

Articles

Aims: To establish the impact of uncomplicated type 2 diabetes on cognitive and neuropsychological performance in midlife. Methods: We performed a cross-sectional study of middle-aged adults with uncomplicated type 2 diabetes and a cohort of healthy control participants. General cognition was assessed using the Montreal Cognitive Assessment test and neuropsychological assessment was undertaken using a detailed neuropsychological assessment battery. Results: A total of 152 participants (102 with type 2 diabetes and 50 controls) were recruited (mean age 52 ± 8 years, 51% women). Participants with midlife type 2 diabetes were more than twice as likely to make an error on …

Evaluating Compressive Properties And Morphology Of Expandable Polyurethane Foam For Use In A Synthetic Paediatric Spine, Nor Amalina Muhayudin, Khairul Salleh Basaruddin, Fiona Mcevoy, Anthony Tansey

Articles

An expandable rigid PU foam can turns into complex shapes, with a shell like structure onthe outside and honeycomb structure on the inside, which can be easily shaped to a vertebraform. The present study aims to determine whether expandable rigid polyurethane foamwas an appropriate substitute for rigid block polyurethane foam to model the trabecularbone. Static compression tests were performed to determine compressive moduli and yieldstresses on three polyurethane foam densities namely 0.16 g/cm3, 0.24 g/cm3and 0.42 g/cm3.Morphology of the PU foams for all densities was also observed. The compressive modulusfor 0.16 g/cm3and 0.24 g/cm3were found varied from 40 to 43 …

Energy Performance Certification: Misassessment Due To Assuming Default Heat Losses, Ciara Ahern, Brian Norton

Articles

Energy Performance Certificates (EPCs) are issued when dwellings are constructed, sold or leased in the EU. Where the cost of obtaining the required data is prohibitive, EPC assessors use nationally applicable default-values. To ensure that dwellings are not assigned a wrongly-higher EPC rating, a standardised thermal bridging transmittance coefficient (Y-value) is typically adopted for all existing dwellings while worst-case overall heat loss coefficients (U-values) are used. Default U-values are applied to a specific building element type (roof, wall, floor etc.) based on building codes and regulations applicable at time of construction. Due to significant building fabric upgrades, default U-values are …

Experimental Investigation Of Flow Pulsation Waveforms In Rectangular Mesochannels For High Heat Flux Electronics Cooling, Jaakko Mcevoy, Sajad Alimohammadi, Tim Persoons

Articles

The ever rising heat fluxes encountered in electronic devices present a challenging thermal engineering problem. Not only is heat transfer enhancement a goal but more recently control of the enhancement is desired, especially in large scale data facilities where the heated outlet coolant fluid may be of use. Flow pulsation is one of the most common active heat transfer enhancement methods studied across all heat sink sizes. While the effects of pulsation have been shown to increase heat transfer under certain conditions there is still disagreement upon its merit for practical applications, with the majority of previous research has been …

A Generalisable Bottom-Up Methodology For Deriving A Residential Stock Model From Large Empirical Databases, Ciara Ahern, Brian Norton

Articles

Specifying representative reference buildings as a prerequisite for calculating cost-optimal energy performance requirements for buildings and building elements. Appropriate characterisation is prerequisite data for an overall national building energy consumption model to produce valid outcomes. Energy Performance Certificates (EPCs) are issued in the EU, for dwellings whenever they are constructed, sold or leased. Where acquiring data for an EPC would be prohibitively costly, nationally applicable default-values are employed for the building envelope thermal transmittance coefficients. Significant levels of retrofits led to the default-values used now being higher than is typical in reality, leading to characterisations of reference dwellings based on …

Thermal Energy Refurbishment Status Of The Irish Housing Stock, Ciara Ahern, Brian Norton

Articles

Energy Performance Certificates (EPCs) are issued for buildings constructed, sold or leased across the EU. Using a generalizable methodology this work exploits Ireland's EPC national dwelling stock database to determine the thermal refurbishment status of Ireland's housing stock. It is estimated in 2014 that; i) 58% of walls were insulated at a mean overall heat loss coefficient or U-value of 0.66 W/m²K, ii) 67% of roofs were insulated at a mean U-value 0.37 W/m²K, iii) 97% of windows were double-glazed, and iv) 53% of floors were insulated to a mean U-value of 0.59 W/m²K. …

Thermal Refurbishment Status Of The Irish Housing Stock, Ciara Ahern, Brian Norton

Articles

Energy Performance Certificates (EPCs) are issued for buildings constructed, sold or leased across the EU. Using a generalizable methodology this work exploits Ireland’s EPC national dwelling stock database to determine the thermal refurbishment status of Ireland’s housing stock. It is estimated in 2014 that; i) 58% of walls were insulated at a mean overall heat loss coefficient or U-value of 0.66 W/m 2 K, ii) 67% of roofs were insulated at a mean U-value 0.37 W/m 2 K, iii) 97% of windows were double-glazed, and iv) 53% of floors were insulated to a mean U-value of 0.59 W/m 2 K. …

A Techno-Economic Analysis Of Current Cooling Techniques In Irish Data Centres, Lee Gibbons, Bryan Coyne, David Kennedy, Sajad Alimohammadi

Articles

This research is part of a comprehensive study to determine reformative actions for cooling regimes within the Irish data centre market. To achieve this goal, preliminary Exergy, Entropy change and operational cost analyses are used. It is determined that there is no clear advantage for using one cooling method over another without knowing the data centres secondary function (e.g. district heating, energy generation). Air cooling technology is a good candidate for a highly reliable system due to the low exhaust temperatures of 30°C. Two-phase immersion is a possibility for economically viable data centres where operational costs are to be minimised, …

Microwave Self-Healing Technology As Airfield Porous Asphalt Friction Course Repair And Maintenance System, Amir Tabakovic, Declan O'Prey, Drew Mckenna, David Woodward

Articles

A problem increasingly faced by airport authorities is the maintenance of runways. Due to their large aircraft loadings associated with take-off and landing operations, runways experience surface deterioration. Poor quality runway surfaces cannot be tolerated in such an environment. Maintenance issues must be carried out to maximise safety and minimise the risk of aircraft damage. A recent development has been the introduction of self-healing technologies such as rejuvenator encapsulation, induction and microwave heating to address these issues. This paper summarises a laboratory investigation to determine the effectiveness of microwave self-healing for crack repair of Porous Friction Course (PFC) used for …

The Influence Of Asphalt Ageing On Induction Healing Effect On Porous Asphalt Concrete, Shi Xu, Xueyan Liu, Amir Tabakovic, Erik Schlangen

Articles

Induction healing is a proven technology which is able to improve the self‐healing capacity of asphalt concrete. Healing is achieved via electromagnetic current produced by passing induction machine, where steel asphalt constituents heat up which in turn soften the bitumen in the asphalt layer, allowing it to flow and close cracks, repairing the damage. This paper reports on the study which investigated the influence of ageing on the healing capacity of Porous Asphalt (PA) concrete. Porous Asphalt concrete mix was prepared first, then subjected to an accelerated (laboratory) ageing process using a ventilated oven. In order to further evaluate the …

A Novel Approach Towards Investigating The Performance Of Different Pvt Configurations Integrated On Test Cells: An Experimental Study, Vivek Tomar, Brian Norton, G. N. Tiwari

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This study elaborates the theoretical and experimental analysis for the effectiveness of different photovoltaic thermal (PVT) configurations along with their building implications. An experiment was performed on especially designed four identical prototype test cells emphasise the building integration photovoltaic thermal (BiPVT) systems. A comparative analysis of four different possible PVT configurations integrated on identical test cells namely; Case 1: Glass-to-glass PV with duct integrated on a test cell, Case 2: Glass-to -glass PV without duct integrated on a test cell, Case 3: Glass to tedlar PV with duct integrated on a test cell and Case 4: Glass to tedlar PV …

Calculation Methods Of Radon-222 Radiological Activity For Norm Plant With Ventilation, Pedro M. Dieguez-Elizondo, Paul G. O'Donohoe, Tomas Gil-Lopez, Juan Castejon-Navas, Miguel A. Gálvez-Huerta

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A procedure is proposed to determine the radiological activity of air present in the working area of a NORM (Naturally-Occurring Radioactive Materials) plant. This NORM plant is located in the United Arab Emirates and is dedicated to the recycling of material and equipment used in oil extraction facilities. Substantial quantities of NORM waste will be present inside the enclosed plant facilities and will exhale significant amounts of Radon-222 into the working environment. The continued inhalation of this gas and its progeny has been shown to cause lung cancer. In order to reduce the concentration level of the aforementioned gas to …

Effect Of High- And Low-Molecular-Weight Hyaluronic-Acid-Functionalized-Az31 Mg And Ti Alloys On Proliferation And Differentiation Of Osteoblast Cells, Sankalp Agarwal, Brendan Duffy, James Curtin, Swarna Jaiswal

Articles

The quality of patient care has increased dramatically in recent years because of the development of lightweight orthopedic metal implants. The success of these orthopedic implants may be compromised by impaired cytocompatibility and osteointegration. Biomimetic surface engineering of metal implants using biomacromolecules including hyaluronic acid (HA) has been used an effective approach to provide conditions favorable for the growth of bone forming cells. To date, there have been limited studies on osteoblasts functions in response to metal substrates modified with the hyaluronic acid of different molecular weight for orthopedic applications. In this study, we evaluated the osteoblasts functions such as …