57 research outputs found
The evolution of Physics textbooks used in Ireland 1860-2022
This paper focuses on the evolution of Physics textbooks used in Ireland from 1860 to 2022, in addition to the Irish influence on early physics textbooks in the latter part of the 19th century. Both Physics and Physics education are continually evolving and so textbooks change in response to that and to the changing priorities of educators. Physics is both experimental and theoretical and the presentation of it has always been multimodal. Physics textbooks tend to include diagrams, demonstrations, experiments, the use of mathematics and derivations, historical references to people, and applications of Physics, among other features. Our research looks at these various characteristics to discern what has changed and what has not, over the course of time. Twenty-eight textbooks were examined in the course of this study. A Physics concept (refraction) and a Physics instrument (electroscope) were chosen for special attention, so that the findings would be firmly rooted in how Physics has been represented in textbooks rather than general textbook publishing trends. A specific analysis of four textbooks by the same two authors across three syllabi is also presented. Our findings show that a great deal has changed in the realm of Physics textbooks, and given that this is the case, it is remarkable how many things changed very little in 162 years
A Parametric Study of Wind Pressure Distribution on Façades Using Computational Fluid Dynamics
This paper uses Computational Fluid Dynamics (CFD) to determine wind pressures on façades for the purpose of efficient design of these elements. An outstand fin arrangement was modeled where local brackets are used to protrude the fins from the building. A parametric study, for both changes in the length of the bracket and the fin, was derived from CFD simulations with 1-in-50-year storm conditions adopted throughout. Further simulations are performed for revised wind directions that ensure all fins are equally exposed to oncoming winds. In total, 15 models are created to act as a representative sample of the total number of possible configurations. Peak values for pressure are used to calculate forces and moments on the fins. These wind loading results were then used to interpolate the values for the remaining façade geometries. From interpreting the trends that are apparent in the relationship of fin size and bracket length to efficient loading, a set of design criteria is established. The optimal façade design is defined, based on placing equal importance onto minimizing the force along the fin’s length and the moment acting at the fin-bracket connection. The performance of some façade elements is shown to worsen the effects of the wind, relative to other designs, with the potential for very negative consequences. Wind direction is shown to have a significant effect on loading, with the magnitude of wind pressures reduced considerably for the worst affected fin, if the sheltering effect is absent between the fins
Understanding Sediment Dynamics at a Shipwreck Site Using CFD Modelling
Shipwrecks are important cultural heritage sites offshore. In many instances, given their often long-term emplacement on the seafloor, they offer natural laboratories to study complex interactions between human-induced obstacles and seabed dynamics. Such interactions and induced sediment mobility also pose significant threats to offshore engineering infrastructure, such as turbine monopile foundations. Traditional methods can struggle to capture the nuance of these processes, with real-world surveys measuring effects only after installation, and laboratory models suffering from scale-down inaccuracies. Computational fluid dynamics (CFD) modelling offers an effective means of investigating the effects of obstacles on seabed dynamics, and by using shipwrecks as proxies for infrastructure, it can utilize long-term datasets to verify its predictions. In this study, high-resolution temporal bathymetric data were used in, and to verify, CFD modelling to investigate the interactions between hydro- and sediment dynamics at a shipwreck site in a tidally dominated wreck site. From this comparison, simulations of bed shear stress and scalar transport correlate well with known areas of erosion and deposition, serving as a basis for future scour prediction studies and creating effective tools in offshore renewable infrastructure planning and de-risking
Portable Bridge WIM Data Collection Strategy for Secondary Roads
A common method of collecting traffic loading data across a large road network is to use a network of permanent pavement-based WIM systems. An alternative is to use one or more portable Bridge Weigh-In-Motion systems which are moved periodically between bridges on the network. To make optimum use of such a system, a suitable data collection strategy is needed to choose locations for the system. This paper describes a number of possible strategies which the authors have investigated for the National Roads Authority in Ireland. The different strategies are examined and their advantages and disadvantages compared. Their effectiveness at detecting a heavy loading event is also investigated and the preferred approach is identified
The use of a dynamic truck-trailer drive-by system to monitor bridge damping
Bridge structures are continuously subject to degradation due to the environment, ageing and excess loading. Periodic monitoring of bridges is therefore a key part of any maintenance strategy as it can give early warning if a bridge becomes unsafe. This article investigates an alternative method for the monitoring of bridge dynamic behaviour: a truck-trailer vehicle system, with accelerometers fitted to the axles of the trailer. The method aims to detect changes in the damping of a bridge, which may indicate the existence of damage. A simplified vehicle-bridge interaction model is used in theoretical simulations to assess the effectiveness of the method in detecting those changes. The influence of road profile roughness on the vehicle vibration is overcome by recording accelerations from both axles of a trailer and then analysing the spectra of the difference in the accelerations between the two axles. The effectiveness of the approach in detecting damage simulated as a loss in stiffness is also investigated. In addition, the sensitivity of the approach to the vehicle speed, road roughness class, bridge span length, changes in the equal axle properties and noise is investigated
A 3D computational fluid dynamics validation study for the Queensferry Crossing Bridge with bus models on the deck
The 2022 Civil Engineering Research in Ireland (CERI) and Irish Transportation Research Network (ITRN) Conference, Dublin, Ireland, 25-26th August 2022In this paper, 3D CFD models of a bridge section of the Queensferry Crossing Bridge including a bus and other secondary structures on the deck are developed in OpenFOAM using the k-ω-SST turbulence model to determine the aerodynamic coefficients. The aerodynamic performance of the bridge deck accounting for several angles of attack with the bus located in various traffic lanes is investigated. The models are then validated with wind tunnel test results and good agreement is found between the 3D CFD models and the wind tunnel tests. The importance of the validated models is that they can be used in the future to study what wind speed should be set as a limit to prevent high-sided vehicles from overturning on the Queensferry Crossing Bridge.University College DublinChinese Scholarship Counci
Full-scale computational fluid dynamics study on wind condition of the long-span Queensferry Crossing Bridge
To date, the majority of numerical modelling [computational fluid dynamics (CFD)] studies on long-span bridges have been carried out on scaled physical models, and without field-data for validation. For the first time, a full-scale bridge aerodynamic CFD study was conducted in this paper. A full-scale three-dimensional CFD model of the middle span and central tower of the Queensferry Crossing, United Kingdom, was created. The aim of this work was accurately simulating the wind field around the bridge. The CFD simulations were developed in OpenFOAM with the k − ω SST turbulence model. Atmospheric boundary layer inflows were configured based on wind profiles provided by a full-scale Weather Research and Forecasting (WRF) model. CFD predictions were validated with field data which were collected from an on-site Structural Health Monitoring System. The simulated fluctuating wind field closely satisfied the characteristic of field data and demonstrated that the modelling approach had good potential to be used in practical bridge aerodynamic studies. Meanwhile, comparisons and sensitivity analyses on mesh density provided a reference modelling approach for any future works on full-scale bridge aerodynamic models. Additionally, a cylindrical-like domain was applied in bridge aerodynamics for the first time and verified as being a convenient and reliable way to be used in bridge studies that involve changes in yaw angle.University College DublinChinese Scholarship CouncilOpen Access funding provided by the IReL Consortiu
A numerical study on the sheltering effects of the central wind barriers on the Rose Fitzgerald Kennedy Bridge
The 2022 Civil Engineering Research in Ireland (CERI) and Irish Transportation Research Network (ITRN) Conference, Dublin, Ireland, 25-26th August 2022This study aims to examine the sheltering effects of central wind barriers installed near the pylons of the Rose Fitzgerald Kennedy Bridge. A full-scale Computational Fluid Dynamics (CFD) model is developed, which includes high-precision geometries of the bridge and the terrain. Simulations using this model are performed at realistic wind conditions as boundary conditions are mapped from mesoscale Weather Research and Forecasting (WRF) simulations. Wind velocities at multiple locations on the bridge predicted by the CFD simulations are compared with field measurement data where a good agreement is reached. The validated model is then applied with bridge geometries with and without the central wind barriers at high wind conditions. Comparisons between these two groups of simulations show that the wind barriers can effectively reduce wind velocities on traffic lanes near the pylon, which validates the current design of the barriers on the bridge.University College DublinChinese Scholarship Counci
\u27Outside their Comfort Zone\u27: Diverse and Engaging Approaches for Students Learning through a Different Discipline
I am an engineer and typically engineering students are assessed using calculation-based exams and written laboratory reports. However, I teach a 5-credit third year module which typically contains 60 architecture students and is compulsory. Simultaneously, these students complete a 20-credit module in studio design involving approximately 30 contact hours per week.
The purpose of this module is to provide architecture students with the necessary training in engineering to fulfil requirements at both a professional and accreditation level.
Whereas calculation-based exams are commonplace in the assessment of engineering students, using them to assess architecture students does not promote effective learning. It was not uncommon for architecture students to fail the engineering-style exam which suited those with a strong background in maths and physics. They seemed relatively unfamiliar with exams as a form of assessment as most of their submissions are studio portfolios. Exams tend to focus student attention on ‘reproductive thinking’ (Boud and Dochy, 2010). Students often end up cramming last minute, engaging in surface learning rather than the deep learning associated with ‘slow scholarship’ when assessment tasks require substantial involvement over time (Gibbs and Simpson, 2005).
An alternative, more inclusive assessment approach was required for this module to improve engagement, to allow equal opportunity to demonstrate learning, to cater for the diversity of students and to reduce the need for individual adaptations for specific students
Special Issue: Applications of Computational Fluid Dynamics to the Built Environment
With ever-increasing computational power and the capability of numerical methods, it is now possible to accurately simulate flow conditions in a virtual environment [...
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